Chemistry and chemical engineering.
Vice-chair: Douglas Masterson, University of Southern Mississippi
Hunter Henry Ballroom A
8:00 Divisional Business Meeting
8:30 THE SITE-DIRECTED MUTAGENESIS OF NEURAL CADHERIN BETWEEN DOMAIN 1 AND DOMAIN 2
Chinela Udemgba*, Nagamani Vunnam, Susan D. Pedigo, University of Mississippi, University, MS 38677
Neural cadherins are members of the cadherin family known for its calcium ion dependent cell adhesion. Classical cadherins contain 5 ectodomains, which are sevenstranded, beta-sheet gobular domains. Domain 1 and 2 were altered by mutating 6 different amino acids (D1C, W2A, R25C, E89A, D134A and D136N). The goal of this work is to discover the role of Ca3 and the linkages between the two domains through the mutations D134A and D136N. The mutant proteins were then over-expressed and purified for later testing. To confirm the mutation, the DNA will be sequenced and the molecular weight of the mutant proteins determined.
8:45 PREPERATION OF HOMOCHIRALLY SIMILAR TYROSINE AND SERINE ANALOGS FROM A COMMON INTERMEDIATE
Dale Rosado* and Douglas S. Masterson, University of Southern Mississippi, Hattiesburg, MS 39406
Recently, there has been much research in the area of unnatural ([alpha],[beta],[gamma], and [delta]) amino acids. It has been shown that incorporation of such unnatural amino acids into protease specific sites in small peptides (such as peptide hormones) increases the in vivo half-life of the peptide. This behavior could make such peptides powerful site specific drug delivery systems to cells, such as cancerous cells (i.e. pancreatic cancer cell lines), which produce and use relatively large quantities of peptide hormones composed of natural ([alpha]a) amino acids. Currently, synthetic routes to synthesize the unnatural analogs of the & aplha;-methyl amino acids easily, inexpensively, and with sufficient enantiomeric yields does not exist. The goal of this project is to develop a method to synthesize all homologues of the unnatural tyrosine and serine analogs via common synthetic intermediates. Furthermore, the synthetic path chosen allows for synthesis of both enantiomers of each in sufficient chemical and enantiomeric yields. This synthetic path uses derivitized prochiral malonate diesters on which a desymmetrization enzyme (i.e. Esterases) can be used to hydrolyze one of the ester substituents to a carboxylic acid. This produces a chiral propanoic acid derivative with an enantiomeric excess of either the (R) or (S) enantiomer. The acid substituent can then be derivatized via a combination of several well-known synthetic paths (Curtius, Wolff, Witting), to give one series of homochirally similar unnatural serine or tyrosine analogs. The current progress into the synthesis of both enantiomers of the & aplha;, [[beta].sup.2.2], and [[beta].sup.3.3] homochirally similar tyrosine and serine analogs will be presented.
9:00 A NOVEL METHOD TO SYNTHESIZE UNNATURAL CYSTEIN ANALOGS
Kinkini Roy and Douglas S. Masterson*, University of Southern Mississippi, Hattiesburg, MS 39406
The aim of this project is to synthesize a wide variety of unnatural cystein analogs (alpha, beta, gamma and carbon analogues of cysteine) from a common synthetic intermediate. This should allow for the construction of amino acids in optically pure form and for the parallel preparation of both enantiomers. The general approach will be as follows: 1) preparation of the prochiral intermediates of malonic acid by using tert-Butylchloromethylsulfide 2) Using esterase to perform a desymmetrization of the prochiral intermediates 3) Analysis of the resulting chiral half ester intermediates 4)Formation of different amino acids from that half ester by using different common organic synthetic pathway. We already prepared both enantiomers of alpha-Methyl Cysteine, both enantiomers of beta-2,2- Methyl Cysteine, both enantiomers of beta-3,3- Methyl Cysteine. Once the synthesis has been achieved in a large scale we shall use them to prepare unnatural Somatostatin analogs with potential biological or enhanced biological activity.
9:15 GRUBBS-TYPE METATHESIS CATALYSTS WITH FUNCTIONALIZED CARBENES FOR APPLICATIONS IN AQUEOUS MEDIA
Adam Roberts* and Hans Schanz, University of Southern Mississippi, Hattiesburg, MS 39406
Over the past four decades, metathesis has evolved to become a highly valuable and versatile tool in organic and polymer synthesis. Since the early 1990s ruthenium-based Grubbs-type metathesis catalysts, such as first generation Grubbs' Catalyst 1 have immensely broadened the application spectrum of this reaction due to their high tolerance towards functional groups as well as moisture and molecular oxygen compared to homogeneous molybdenum-based systems.
The true potential of aqueous metathesis, i.e. its scope and limitations, has yet to be explored. The concept, while proven to be feasible for certain ruthenium (Ru)-based Grubbs-type catalysts, we find that water-soluble examples of such catalysts with an excellent performance profile remain elusive. Our research targets the synthesis of novel Ru-based metathesis catalysts which bear functionalized carbene moieties 2-5 which should enhance catalyst solubility in aqueous solvents for application in Ring Opening Metathesis Polymerization (ROMP) of water-soluble norbornene derivatives (Figure 1). Therefore, we will exchange the initial carbene of highly active metathesis catalysts using functional olefins. ROMP will retain the function carbene as a tethered group, thus the catalyst will not change its solubility profile. Due to the favorable ratio of the rate of initiation vs. propagation, first generation catalysts are favored to provide materials with narrow molecular weight distributions under "living" conditions. We will present recent results on the catalyst syntheses and initial polymerization experiments.
9:30 REVERSIBILE INHIBITION/ACTIVATION OF GRUBBS' CATALYST
Steven J. P'Pool*, Nancy J. Berger, and Hans Schanz, University of Southern Mississippi, Hattiesburg, MS 39406
Over the last four decades olefin metathesis has increasingly become an important synthetic tool in organic and polymer chemistry. Grubbs' first and second-generation catalysts are the most common catalysts used for these transformations. 1 Various ligand modifications have been designed to accommodate special applications, such as temporary catalyst inhibition for ROMP of DCPD2. Little research has been invested in catalyst systems, which can reversibly be activated and inhibited. Our project investigates the influence of electron-rich N-donor ligands on the catalytic activity of Grubbs' catalyst. We have found that addition donor ligands such as 1-methylimidazole or 4-dimethylaminopyridine (DMAP) are capable of completely inhibiting the metathesis reaction, such as RCM and ROMP, when at least two equivalents are used to completely produce a six-coordinate species of low activity. Upon acid addition, the initial Grubbs' Catalyst is restored and the metathesis reaction proceeds according to the additive-free catalyst. We will present new synthetic and kinetic data on reversible catalyst inhibition/activation of Grubbs' catalyst.
9:45 SYNTHESIS OF UNNATURAL ISOLEUCINE ANALOGS FROM A COMMON INTERMEDIATES
Sandipan Dawn* and Douglas S. Masterson, University of Southern Mississippi, Hattiesburg, MS 39046
he aim of this project is to synthesize a wide variety of unnatural isoleucine analogs ([alpha], [beta] and [gamma]) from a common synthetic intermediate. This should allow for the construction of amino acids in optically pure form. The general approach will be as follows: 1) preparation of the diastereotopic intermediates of malonic acid 2) Using esterase to perform a desymmetrization of the intermediates 3) Analysis of the resulting half ester intermediates 4)Formation of different amino acids: [alpha](Curtius),[beta](Wolff,Curtius),[gamma](Wittig, Curtius) from that half ester. Once the synthesis has been achieved we can use that to prepare unnatural peptides with potential biological or enhanced biological activity. These unnatural amino acids can be used to replace their natural counterparts in some hormones (eg Neurotensin) to increase their half-life inside a biological system. New Synthetic Approaches to Water-Soluble Ruthenium-Based Second Generation Olefin Metathesis Catalysts
10:15 NEW SYNTHETIC APPROACHES TO WATER-SOLUBLE RUTHENIUM-BASED SECOND GENERATION OLEFIN METATHESIS CATALYSTS
Hans Schanz (1*), Nancy J. Berger (2), and Steven J. P'Pool (1), (1) University of Southern Mississippi, Hattiesburg, MS 39406 and (2) Lycoming College, Williamsport, PA 17701
Despite environmental and commercial benefits, metathesis in aqueous media has not been vigorously pursued over the last decade apart from conceptual studies. Various factors have contributed to the slow development in this area: 1) Dissatisfactory Cost/Benefit Ratio: Water-soluble phosphines are expensive and cumbersome to synthesize. Commercially available phosphine ligand Cy2P(CH2)2NMe3+Cl- is near ten times the cost of PCy3. Thus, competitive water-soluble olefin metathesis catalysts need to be: A) Highly active designs based on less expensive water-soluble NHC-ligands, B) Recyclable to improve the cost/benefit ratio. 2) Hydrolysis of Catalysts Bearing Water-Soluble NHC-ligands: Protic solvents often cause slow hydrolysis of the metal-NHC bond. This observation was made for various catalysts. Steric protection of this bond is needed. 3) Problematic Catalyst Synthesis: The NHC ligand/phosphine exchange reaction at first generation catalysts, to date the method of choice for the synthesis of second generation catalysts, requires solvents of low polarity. This renders almost all ionic NHC-ligand designs unfeasible as they display low solubility and thus very slow conversion rates. We have recently synthesized a ruthenium carbene complex which is a reversibly water-soluble, pH-responsive catalyst which has potential for improved catalyst separation and recycling. Only a handful of water-soluble designs have been reported thus far, none of which is pH-responsive. the neutrally charged catalyst is soluble in organic media, highly active and bears an NHC ligand with two dimethylamino groups. Upon acid addition, the catalyst should be suitable for reactions in aqueous media. We will present results on the synthesis, thermal stability and catalytic activity of both, neutral and double-protonated catalysts. We propose, such catalysts can be effective in aqueous and organic media, can perform co-polymerizations of largely different monomers, and can be recycled upon pH change.
10:30 SPECIFIC DELIVERY OF ANTI-SURVIVIN SIRNA TO KB CELLS BASED ON FOLATE RECEPTOR
Jun He*, University of Southern Mississippi, Hattiesburg, MS 39406
The recent discovery of RNAi has provided a powerful means of regulating gene expression. RNAi is not only revolutionizing the ways bioscientists perform basic science research such as studying gene function and mechanism, but also presents immense potentials for developing the next generation biomedicine with unmatched high potency and low side toxicity. The advancement of understanding of cellular functions at molecular levels has revealed differences in gene expression profiles between normal cells and cancerous cells. Such differences may become the basis for biomedical intervention of cancer genesis and progression. For example, folate receptor (FR) is not expressed in normal cells but high levels of FR expression are associated with certain cancers, which require a steady supply of folic acid for the biosynthesis of nucleic acids. Based on expertise in chemistry, RNA, and enzomolgy, we are exploiting FR as a cancer-specific delivery vehicle of anti-survivin siRNA. Survivin belongs to the family of inhibitors of apoptosis protein (IAP). Expression of survivin is essential for cancer proliferation. Down regulation of survivin can induce apoptosis of cancerous cells. Therefore, our experiments may lead to new cancer therapy based on RNAi.
10:45 DOWN REGULATION OF VEGF AND VEGFR BY RNAI THROUGH CANCER-SPECIFIC DELIVERY
Yilin Zhang*, Yanlin Guo, and Faqing Huang, University of Southern Mississippi, Hattiesburg, MS 39406
Angiogenesis is a process of initiation, growth, and development of new blood vessels from pre-existing ones. Angiogenesis is critical for cancer genesis and tumor growth. Numerous studies have established vascular endothelial growth factor (VEGF) as an essential factor for angiogenesis. Cells can obtain VEGF by either self VEGF expression or from extracellular environment. With the powerful RNAi technology, we are investigating siRNA's effect against both VEGF and VEGFR. Using the transfection agent Lipofectamine and quantitative real time PCR, we have demonstrated that our self-designed and prepared siRNAs are efficient inhibitors of VEGF and VEGFR expression. However, Lipofectamine-based siRNA is not cell specific and displays a certain degree of toxicity. Taking the advantage of high level folate receptor (FR) expression by certain cancer cells, we are developing cancer-specific delivery tools for siRNA application. By binding and stabilizing siRNA and using cancer-specific receptors, the new siRNA delivery agents will lead to significant improvement on siRNA delivery, paving the way for applications of RNAi in biomedicine.
11:00 THE EFFECT OF ROTATIONAL ACCELERATION ON DIFFUSION BETWEEN MISCIBLE FLUIDS
John A. Pojman (1*), Gloria Viner (1), and Renato Lombardo (2), (1) University of Southern Mississippi, MS, 39406 and (2) Universita di Palermo, Italy
We studied three types of miscible systems in a spinning drop tensiometer. The first system, isobutyric acid and water, exhibits an Upper Critical Solution Temperature at 26.5[degrees] C above which it is miscible in all proportions. The second, butanol and water, has a solubility limit. The third system, dodecyl acrylate and poly(dodecyl acrylate), is miscible in all proportions. We analyzed the effect of the rotational acceleration and show why the isobutyric acid system is more affected by writing the equation for the flux and including a term for the buoyancy. Finally, we explain why the first two systems retain very sharp concentration gradients even as one fluid dissolves into the other but the monomer-polymer system does not.
11:15 THE USE OF SQUARAINE DYES AS MOLECULAR SENSORS
Karl Wallace*, University of Southern Mississippi, Hattiesburg, MS 39406
Squaraine molecules are an unusual class of molecules that have some unique physical properties. Squaraine dyes are interesting materials to work with and have been used for many applications in materials science. For example, electrophotography, optical data storage, and non-linear optics, have all incorporated squaraine dyes. An interesting property of squaraine dyes is the sharp intense Q-band seen at wavelengths between 600-670 nm, with extinction coefficients ([epsilon]) [greater than or equal to] [10.sup.5] [cm.sup.-1] [M.sup.-1]. This intense absorption band is a very attractive property for sensor design, as it is close to the near infrared (NIR) region of the spectrum, which is desirable for integration with optical instrumentation. However, squaraine dyes have only recently been utilized as molecular sensors in the field host-guest recognition (an area of supramolecular chemistry). For example, in their use for the detection of trace elements, such as, iron and zinc. Iron and zinc are important in biological systems and in the environment. Many of us are aware that our cells contain metal ions that are "tied" up in proteins. However, chelatable or "free" trace elements can also be found in small quantities, and they can have a negative impact on our bodies. These can be the source for metabolic reactions to occur within the cell and are often a site for the generation of radicals. The use of squaraine dyes as molecular scaffolds for the detection of trace elements either by colorimetric means (i.e., can we see a visual color change?--"naked eye" detection) or using fluorescence spectroscopy, which enables us to detect trace elements at lower concentrations, will be discussed.
11:30 INVESTIGATION OF CLAY INTERCALATION/EXFOLIATION MECHANISMS IN EPOXY RESINS
Yongcheng Zhang* and Charles U. Pittman, Jr., Mississippi State University, Mississippi State, MS 39762
Montmorillonite clay is an important nano-layered material. Intercalation and exfoliation are common methods to make the best use of the clay layers. Many factors affect the intercalation/exfoliation process. The effect of intragallery epoxy polymerization rate, extragallery epoxy polymerization rate and diffusion rate was investigated. The effect of overall epoxy polymerization rate was investigated by adding very small amounts of catalyst to the clay/epoxy system so that the polymerization rate would vary without much change in the initial viscosity. The anhydride curing agent (HY 918) was used because it cures epoxy resins with very low curing speed even at fairly high temperatures. The use of high temperature will greatly increase the diffusion rate into the galleries. The composites cured with lower catalyst concentrations had better clay dispersions and larger d-spacings. High temperature pre-treatment of clays with epoxy resin was also conducted to investigate the effect of diffusion. This pre-treatment of pillared organo-clays improved the d-spacing greatly, but little change was observed for clay without any pillaring agents. The effect of intragallery polymerization rate was also investigated by using clays with different pillaring agents. In summary, higher diffusion rates and lower overall polymerization rates favor the intercalation/exfoliation of Montmorillonite clay in epoxy resin systems.
Hunter Henry Ballroom A
1:30 ACYLATION OF 2-PROPENYL-2-OXAZOLINE AND SUBSEQUENT DIELS-ALDER REACTIONS
Yingquan Song (1*), Hua Guo (1), Guozhong Ye (1), Aihua Zhou (2), and Charles U. Pittman, Jr. (1), (1) Mississippi State University, Mississippi State, MS 39762 and (2) University of Kansas, Lawrence, KS 66045
2-Propenyl-4,4-dimethyl-2-oxazoline, 1, was synthesized by acylation of 2-amino-2-methyl propanol with crotonyl chloride and subsequent ring closure upon treatment with mesyl chloride. 1 reacts with benzoyl chloride to give a cyclic ketene acetal 2, where both the nitrogen and the |A carbon have been acylated. This compound is an electron rich diene. Therefore, we attempted using the Diels-Alder reaction with maleic anhydride to generate the adduct 3 which has a dense and rich functionality. This reaction proceeded readily. Compound 3 is of interest because the exocyclic double bond is part enamine, part vinyl ether, part diene and part |A, |A-unsaturated ketone simultaneously.
1:45 DETERMINATION OF ANTIOXIDANT CAPACITY OF HYDROXYFLAVONES AND HYDROXYCHROMONES TO FURTHER UNDERSTAND THE MECHANISM FOR PROTECTION OF WOOD AGAINST FUNGAL DECAY
Christopher V. Ruhs*, Nursen Binbuga, Tor P. Schultz, and William P. Henry, Mississippi State University, Mississippi State, MS 39762
Decomposition by decay fungi renders wood and wooden structures unusable resulting in huge negative economic consequences. Wood products are currently treated with metallic biocides to prevent biodeterioration, but these preservatives are coming under increasing scrutiny. Thus, a need exists to develop environmentally-benign, totally organic wood preservatives. It is proposed that decay fungi initially attack the cell wall of wood using radicals generated via Fenton chemistry. Hydroxychrom-ones and hydroxyflavones inhibit fungal wood decay. It is of interest to determine the mechanism by which these compounds function to protect wood in order to develop alternative non-metallic wood preservatives. As part of this effort, a number of hydroxychromone and hydroxyflavone compounds' capacities for scavenging free radicals were evaluated. Compounds studied were morin, kaempferol, 3-hydroxyflavone, 5-hydroxyflavone, 3-hydroxychromone and 5-hydroxychromone. Interestingly, both 5-hydroxyflavone and 5-hydroxychromone protect wood from decay fungi but do not show significant ability to neutralize the radical cation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) [ABTS[dot]?+] in ethanol. This suggests that these two compounds are able to protect wood by mechanisms other than radical-scavenging and may be evidence that complexation with metal ions is the predominant mechanism by which hydroxyflavones protect wood from decay fungi.
2:00 DIELECTROPHORETIC FIELD AND FREQUENCY DEPENDENCE ON RED BLOOD ABO CELL TYPES
Prashant Reuben Daggolu* and Adrienne R. Minerick, Mississippi State University, Mississippi State, MS 39762
Dielectrophoresis is a phenomenon of the movement of particles in a non-uniform electric field  with the advantage that it can be used for polarizable particle separations and characterizations. This nonlinear electrokinetic tool is a field strength and frequency dependant phenomenon . Dielectrophoresis has already found a variety of application in biological research such as separation of malarial cells and cancer cells from healthy cells. The response of red blood cells to a dielectrophoretic field has been of a particular interest in this work due to its easy accessibility and prominent role in medical diagnostics. Dielectrophoresis of red blood cells is being studied to assess its usefulness as a tool in portable, point-of-care, medical diagnostic microdevices. Previous works established that red blood cells translate across electric field lines to form chains in two dimensional dielectrophoretic fields. Our research has discovered that the overall movement of the cells in the dielectrophoretic field is characteristic of their ABO blood type. In the present work, we investigate the dependency of dielectrophoretic field strength and frequency on the movement of positive ABO red blood cell types. Experiments were performed at five different field strengths and six different frequencies to assess and quantify their movements and behaviors in the dielectrophoretic field. Results will be reported for each blood type; comparisons and conclusions will be drawn from the behaviors observed. The study will potentially elucidate any blood type dependencies and determine optimal field strength and frequency for each blood system. These results will be important in the future development of dielectrophoretic medical diagnostic kits.
2:15 SNELL'S LAW OF REFRACTION OBSERVED IN THERMAL FRONTAL POLYMERIZATION
Veronika Viner*, John A. Pojman, Shanna Lavergne, Melanie Winsper, and Burcu Binici, University of Southern Mississippi, Hattiesburg, MS 39406
We demonstrated that Snell's Law of refraction can be applied to thermal fronts propagating in a domain with two different inherent velocities. We used the frontal polymerization of a triacrylate with clay filler that allowed different domains containing different concentrations of a peroxide initiator to be molded and placed in contact. Because the front velocity is a function of the initiator concentration, it was possible to create a bifurcated domain in which the front velocity differed in each half of the domain. By measuring the normal front velocity and the angle of refraction, we were able to verify that Snell's Law can be applied to thermal frontal polymerization.
2:30 POLYAMMONIUM CRYPTANDS FOR ANION BINDING
Md. Alamgir Hossain*, Jackson State University, Jackson, MS 39217
Anion binding is achieved by week bond interactions of the ligands with anions. The main forces responsible for the binding are hydrogen bonding or electrostatic interactions between the ligands and substrates, which mimic many natural processes in biology. Polyammonium cryptands are bicyclic compounds, which are suitable for encapsulating anion in the cavity center. NMR binding of the ligands with inorganic anions, and crystallographic structures of the encapsulated anions will be presented.
2:45 PROS AND CONS OF MICROW AVE OVEN USE IN ORGANIC SYNTHESIS
Mudlagiri B. Goli, Mississippi Valley State University, Itta Bena, MS 38941
Microwave synthesis is in use for last couple of decades. I had the opportunity to test drive it. The drive began here in Mississippi Valley State University and then in Dr. Pittman's laboratory in Mississippi State University. The compounds of interest were Oxazoline and Thiazoline derivatives. They were subjected to acylation reactions using microwave oven. The focus was to check the effectiveness of doing known synthesis, using a microwave and to see if we can speed up the reaction. Second wish was to see if we can get the product that is not possible in normal thermal reflux reactions. Sure enough Microwave worked better, it was fast, but has limitation. It did not give any new desired products that were not forming in regular thermal reactions. The bad part is the cost of the machine. The presentation will dwell more in details on a new toy every Organic Chemist would love to have!
3:15 SMALL-ANGLE NEUTRON SCATTERING STUDY ON A STRUCTURAL CHANGE IN THE POLYMERIZATION OF THE DODECYL ACRYLATE MICROEMULSION
Jolanta Marszalek (1*), Kirt Page (2), and John A. Pojman (1), (1) University of Southern Mississippi, Hattiesburg, MS 39406 and (2) National Institute of Standards and Technology, Gaithersburg, MD 20899
Hydrophobic polymer films having an aqueous phase distributed throughout the matrix are formed by polymerizing a solution of dodecyl acrylate and 1,6 hexanediol diacrylate containing nanometer-sized drops of water stabilized by chemical name (AOT). Photopolymerization-induced aggregation of the water drops and phase separation occurs, as the initially clear solutions become opaque films. The polymerized films become clear, as the relative humidity is reduced. The transition from opaque to clear films is reversible provided that the film did not become completely dry and form cracks. In this study, SANS is used to determine not only size distribution of the micelles in dodecyl acrylate-based microemulsion, but also change in the structure of the microemulsion upon polymerization. For microemulsions prepared with the same [D.sub.2]O-to-AOT ratio, but increasing [D.sub.2]O content the organization of the micelles is constant. As predicted, a change is observed in the micelles' organization with an increasing [D.sub.2]O-to-AOT ratio. Upon polymerization, the organization of the surfactant changes. The spherical structures assume lamellar shape. In addition, increasing water content has definite influence on the distance between surfactants' layers.
3:30 ELECTROCHEMICAL FORC: A NEW CYCLIC VOLTAMMETRY METHOD FOR EXAMINING PHASE TRANSITIONS
Ibrahim Abou Hamad (1*), Daniel Robb (2), and Per Arne Rikvold (3), (1) Mississippi State University, Mississippi State, MS 39762, (2) Clarkson University, Potsdam, NY 13699, and (3) Florida State University, Tallahassee, FL 32306
We present a new experimental technique for cyclic voltammetry, based on the first-order reversal curve (FORC) method for analysis of systems undergoing hysteresis. The advantages of this technique are demonstrated by applying it to dynamical models of electrochemical adsorption. The method can not only differentiate between discontinuous and continuous phase transitions, but can also quite accurately recover equilibrium behavior from dynamic analysis of systems with a continuous phase transition. Experimental data for the Electrochemical FORC (ECFORC) analysis could easily be obtained by simple reprogramming of a potentiostat designed for conventional cyclic-voltammetry experiments.
3:45 THE USE OF LASER LINE DEFLECTION TO DETERMINE THE DIFFUSIVE BEHAVIOR OF METHYL METHACRYLATE AND POLY (METHYL METHACRYLATE) FOR ISOTHERMAL FRONTAL POLYMERIZATION MODELS
John Russell McPherson*, Joshua S. Hanna, and Lydia Lee Lewis, Millsaps College, Jackson, MS 39210
Isothermal Frontal Polymerization (IFP) is a self-sustaining, directional polymerization that occurs when a solution of monomer and thermal initiator come in contact with a polymer seed and create a viscous region where a higher polymerization rate, the gel effect, occurs. IFP can be used to produce gradient refractive index materials (GRINs), which are materials that contain a spatial change in their refractive index. These materials are used industrially in laser and lens applications, and mathematical models of IFP have been constructed in hopes of producing improved GRINs. One drawback to these models is the lack of information in the literature on the two diffusion processes that occur in IFP: liquid monomer diffusing into the solid polymer seed and the solid polymer seed diffusing into the liquid monomer. We used laser line deflection (or Weiner's method) to monitor these two diffusion processes for the methyl methacrylate/poly(methyl methacrylate) system and determined for all tested temperatures and for three different polymer molecular weights that the high molecular-weight (or glassy) polymers used in IFP exhibit Case II diffusion. In addition, we determined that laser line deflection can simultaneously illuminate three of four possible regions within Case II diffusion (pure liquid, swollen glassy polymer, and pure glassy polymer) and can monitor their movement over time.
4:00 EVALUATION OF PYRENE-BASED STATIONARY PHASES FOR METALLIC NITRIDE FULLERENE HPLC SEPARATIONS
Katie Carpenter (1*), Mary Mackey (2), Paige Phillips (2), and Steven Stevenson (2), (1) Mississippi University for Women, Columbus, MS 39701 and (2) University of Southern Mississippi, Hattiesburg, MS 39406
The separation and purification of metallic nitride fullerenes (MNFs) can be performed by HPLC. However the cost for these specialty HPLC columns is exorbitant. Motivations for this work include the following: (1) investigating the feasibility of a more economical stationary phase and (2) synthesizing and evaluating new stationary phases prepared in our labs. We have prepared an array of functionalized silicas and subsequently packed our own HPLC columns using a slurry method at high pressure (9000 psi). The columns were evaluated by calculating the capacity factors for C60, C70, and Sc3N@C80 MNFs. Results indicate a successful separation of MNFs from contaminant empty-cage fullerenes.
4:15 THE CONTROLLED POLYMERIZATION OF NEW CATIONIC EXO-7-OXA-NORBORNENE DERIVATIVES USING COMMERCIALLY AVAILABLE GRUBB'S CATALYSTS
David Rankin* and Andrew Lowe, University of Southern Mississippi, Hattiesburg, MS 39406
Ring opening metathesis polymerization (ROMP) is a transition metal catalyzed polymerization technique belonging to a family of metathesis reactions that allow for carbon-carbon bond formation by double bond scrambling. ROMP is applicable to strained cyclic alkenes such as norbornene derivatives allowing for the synthesis of polymers with unsaturation along the polymer backbone. This polymeric unsaturation can allow for further chemistries, thus producing polymers with new and interesting properties. The advent of well-defined ruthenium metal catalysts, e.g. Grubb's catalyst, allows for the synthesis of highly functionalized polymers in a controlled/"living" fashion. To date, we have synthesized a series of new cationic exo-7-oxanorbornene derivatives by reacting exo-tertiary amine-functionalized 7-oxanorbornene with benzyl, butyl, ethyl, propyl, pentyl, and octyl bromide/chloride. Conditions were optimized for their subsequent polymerization under homogeneous conditions in organic media. Such conditions facilitate the use of the commercially available first generation Grubb's catalyst, therefore negating the need for complex, multi-step initiator synthesis or protecting group chemistries in the preparation of cationic norbornene Cbased materials. These polymerizations proceed rapidly in a controlled fashion resulting in low polydispersity indices, the ability to prepare (co)polymers with pre-determined molecular weights and the ability to prepare materials with more advanced architectures including statistical and block copolymers. Additionally, other halogenated alcohols, such as 2,2,2-trichloroethanol and 1,1,1,3,3,3-hexafluoroisopropanol, were found to be effective cosolvents that allow for controlled/"living" polymerizations.
6:00 Divisional Poster Session
Location: Bost Auditorium North
Posters may be set up between 4:00p and 4:30p
SOLUBILITY OF OLEIC ACID OXIDATION PRODUCTS IN SUPERCRITICAL CARBON DIOXIDE
Darrell L. Sparks (1*), L. Antonio Estevez (2), Rafael Hernandez (1), W. Todd French (1), Rebecca K. Toghiani (1), Hossein Toghiani (1), Earl Alley (1), and Mark Zappi (3), (1) Mississippi State University, Mississippi State, MS, 39762, (2) University of Puerto Rico, Mayaguez, PR 00681 and (3) University of Louisiana, Lafayette, LA 70504
Renewable feedstocks for producing chemicals, intermediates, and fuels are necessary to reduce dependence on petroleum. Many chemicals used for manufacturing consumer products could be made using lipids derived from vegetable oil, animal fat, and microorganisms. For example, oleic acid is a common unsaturated fatty acid that can be oxidized with ozone to produce azelaic acid and pelargonic acid. These products are used in the production of plastics, pharmaceuticals, herbicides, and other products. The conventional method for performing the oxidation reaction involves passing ozone through oleic acid. Since ozone is a gas and oleic acid is a liquid under reaction conditions, mass-transfer limitations exist. The main objective of the project is to eliminate the mass-transfer limitations using supercritical carbon dioxide (SC-C[O.sub.2]) as a reaction medium. By allowing the two reactants to coexist in the same phase, the reaction may proceed at a faster rate. Additionally, if a significant difference exists between the solubility of azelaic acid and pelargonic acid in SC-C[O.sub.2], a supercritical fluid separation can be used to fractionate the products minimizing downstream unit operations. In order to determine operating conditions, a secondary objective is to determine and model the solubility of oleic, pelargonic, and azelaic acid in SC-C[O.sub.2]. The solubilities of azelaic acid and pelargonic acid were determined at pressures of 100, 133, 167, 200, 233, 267, and 300 bar at 40[degrees]C and 60[degrees]C. The data were modeled using the Peng-Robinson equation of state, the Chrastil equation, and the Mendez-Teja equation.
SYNTHESIS AND CHARACTERIZATION OF SOME SCHIFF BASE COMPLEXES OF VANADIUM(V)-SIGNS OF SOME EXCITING EFFECTIVE INSULIN-LIKE PROPERTIES.
Alvin A. Holder (1*), Gabriel R. Harewood (2), Kerry-Ann Green (2), Paul T. Maragh (2), and Tara P. Dasgupta (2), (1) University of Southern Mississippi, Hattiesburg, MS 39406 and (2) University of the West Indies, Mona, Jamaica
Several new vanadium(V) complexes with Schiff bases as ligands were synthesized. The vanadium(V) complexes were characterized by UV-visible, IR, NMR, and X-ray diffraction. Electrochemical studies were carried out on the complexes in DMSO solution so as to determine the redox potentials of the vanadium center and the effect of ligand environment on the redox potential of vanadium(V). Effectiveness of these compounds in lowering blood glucose in STZ-induced diabetic rats is being investigated.
OXIDATIVE STABILITY OF CATFISH AND SOYBEAN BIODIESEL
Supanee Danviriyakul (1*), Saowalee Jongrattananon (2), and Juan Silva (2), (1) Chandrakasem Rajabhat University, Thailand and (2) Mississippi State University, Mississippi State, MS 39762
The stability of biodiesel depends on the quality of the feedstock, transesterification process, environmental conditions, and other factors. There are many methods to measure oxidative stability including peroxide value, anisidine value, free fatty acids, induction period and others. The induction period is being tested as a standard measure of oxidation of oils and biodiesel. The induction period refers to the time it takes a sample to volatilize into acids at a rapid rate, when heated under an air flow. The European Union sets biodiesel at an induction period of 6 or more hours. To achieve this, antioxidants will have to be added to the product. Pure biodiesel from soybean was more stable than that of catfish, 4.91 and 0.54 h, respectively. However, their stability was enhanced by the addition of antioxidants. This was in the order of TBHQ > PrG > BHA > [alpha]a-Tocopherol. An induction time of up to almost 60 h was obtained from soybean biodiesel with 3200 ppm of TBHQ. Longer induction time was expected if additional TBHQ would have been used in catfish biodiesel at higher concentration than 800 ppm used in this study. Among the four antioxidants tested, [alpha]a-tocopherol was the least effective, especially with soybean biodiesel.
MULTILAYER KERATIN FILMS VIA LAYER-BY-LAYER ASSEMBLY TECHNIQUE
Brittany Jones (1*), Jun Li (1), Robert A. Smith (2), and Sarah E. Morgan (1), (1) University of Southern Mississippi, Hattiesburg, MS 39406 and (2) Keraplast Technologies Ltd
Keratins are the major fibrous proteins found in the outer coverings of animals, including human hair, wool, nails and horns. Keratins have been demonstrated to provide wound healing capability and biocompatibility, and thus keratin based coatings are of interest for a wide range of biomedical and personal care applications. In this work, the layer-by-layer polyelectrolyte assembly technique was explored to produce useful keratin coatings. Keratin produced via the oxidative sulfitolysis of wool was employed as the polyanion and ammonium functionalized cellulose (polyquarternium) was employed as the polycation. The multilayer films were analyzed via ellipsometry and atomic force microscopy. The factors which might influence the layer-by-layer assembly process, including changes in pH, salt concentration and molecular weight, were investigated. It was found that stable multilayer keratin films were obtained via the LBL process, and salt concentration and pH of the solution were critical factors in determining film properties. Acknowledgment is made to the donors of the American Chemical Society Petroleum Research Fund for support of this research.
THE REACTIONS OF 2-METHYL-4,5-DIHYDROIMIDAZOLES AND 2-METHYL-1,4,5,6-TETRAHYDROPYRIMIDINES WITH ACID CHLORIDES
Guozhong Ye (1*), Yingquan Song (1), Aihua Zhou (2), Charles U. Pittman, Jr. (2), (1) Mississippi State University, Mississippi State, MS 39762 and (2) University of Kansas, Lawrence, KS 66045
2-Methyl-4,5-dihydro-1H-imidazole(1), 1,2-dimethyl-4,5-dihydro-1H-imidazole(2), 2-methyl-1,4,5,6-tetrahydropyrimidine(3), and 1,2-dimethyl-1,4,5,6-tetrahydropyrimidine(4) react with acid chlorides under mild conditions to give N,N\'-diacyl- & beta-keto-cyclic-ketene-N,N-acetals(5)(eq.1),(Z)-3-((2-amidoethyl)(methyl)amino)-3-oxo-1-prop-1-enyl benzoate (6) (eq.2), N,N\'-diacyl-cyclic-ketene-N,N-acetals (7) (eq.3), N-acyl- & beta, & beta\'-diketo-cyclic-ketene-N,N-acetals (8) (eq.4), respectively. The extent of acylation and sites acylated are dependent on the size of N,N-ring system (5 or 6-membered ring) and the substitutions on the nitrogen atom (H, Me, acyl).
THE ROLE OF SUPERACIDS IN CATALYTIC CRACKING OF OLEIC ACID
Tracy J Benson*, Rafael Hernandez, W Todd French, Mark G White, Earl G Alley, and William E Holmes, Mississippi State University, Mississippi State, MS 39762
Although the growing demand for renewable fuels has led to an increase in annual production of biodiesel from 0.5 to 75 million gallons, biodiesel production is mainly limited to plant oils such as soybean and canola and gives off glycerol as an unwanted byproduct. Therefore, a new biofuel is needed that can utilize a wider variety of lipids without producing unwanted byproducts. Municipal sewage sludge and cultivated algae are just two lipid sources that could be used to produce green diesel. These lipids (i.e., glycolipids, phospholipids, sphingolipids, etc.) could be cracked with superacids to produce diesel range organics that can be burned in compression ignition engines. In this study, oleic acid, a major fatty acid component of many potential lipid feedstocks, was reacted at 0[degrees]C using triflic acid as the protonating catalyst. Oleic acid was found to crack into liquid and gaseous products. Liquid products were analyzed by NMR, FTIR, and GC/MS. The liquid fraction is composed of a mixture of C9-C14, C16 and C18 free fatty acids. This is indicative of alpha and gamma cracking analogous to that found in heterogeneous catalysis of petroleum fuels. Both, straight and branch chain isomers are formed for many of the carbon-lengths. Furthermore, decarboxylation to form diesel range organics can be achieved using high-temperature, transition metal catalytic reactions.
SYNTHESIS OF NATURALLY OCCURING POLYPHENOLS WITH ANTITUMOR POTENTIAL
Sidika Polat Cakir, Matthew S. O'Brien*, and Keith T. Mead, Mississippi State University, Mississippi State, MS 39762
Epicalyxin J is one of many diarylheptanoids found in the Chinese plant Alpinia blepharocalyx that are known to possess antiproliferative activity towards certain types of cancer cells. Because the absolute stereochemistry of epicalyxin J is not known, our work is directed towards the synthesis of this diarylheptanoid for structure confirmation and further cancer screening. Owing to the complexity of epicalyxin J, a simpler model structure will be synthesized to help determine the stereochemical influences of an intramolecular cyclization approach to the core, fused, tricylic ring system. Molecular orbital calculations for the model structure predict that the desired isomer will be favored due to pi-pi stacking of aromatic rings.
INSPIRATION THROUGH CHEMISTRY EDUCATION
Michelle Windham (1), Marcus Steele (1*), and Mark Stovall (2), (1) Delta State University, Cleveland MS 38733 and (2) Sunflower Landing Adolescent Treatment Facility, Clarksdale, MS 38614
Rural schools in the Mississippi Delta lack the funding to provide adequate resources for offering strong courses in the physical sciences. The underserved youths are at a higher risk to become involved in illegal activities such as drugs and other forms of criminal activity. This premise of this project is to develop a set of focused activities in the physical sciences that can used to empower trouble youths as a means of diverting them from future criminal activity. The study, conducted over a six month time period, develops teaching styles and materials appropriate to achieve the desired goal. The instruction is based on a guided inquiry technique in which lectures are designed around each laboratory activity. Due to the limited laboratory facilities, the chosen activities will utilize reagents commonly found in homes and do not involve the use of open flames, corrosives or otherwise dangerous materials. Eighteen students were involved in the project ranging in age from 13 to 18 with varied science backgrounds. The lessons were conducted once a week for one and a half hours in an "open setting" in which they could discuss the concepts freely. The facility staff were closely involved in the activities and assisted by encouraging the slower students. Students were asked to complete assignments in the interim periods and record any questions about the previous week's activity. These questions were submitted and answered anonymously to provide an environment free of ridicule from peers. Each lesson was composed of approximately 30 minutes of lecture centered on the topics examined in the activities. The remainder of the class time involving in performing the activities. All activities were taken from the website, www.about.com.
ELECTRIC-ARC PLASMA SYNTHESIS OF METALLIC NITRIDE FULLERENES
Howard Louie Coumbe*, Corey Thompson, Curtis Coumbe, Paige Phillips, Mary Mackey, and Steven Stevenson, University of Southern Mississippi, Hattiesburg, MS 39406
The electric-arc synthesis of metallic nitride fullerenes consists of the vaporization of metal-packed graphite rods in a helium atmosphere. Nitrogen is introduced into the reactor via a gas inlet or as a dopant in the packed graphite rod. Results suggest that key parameters to optimize include gap voltage, current, and pressure within the reaction chamber. Our discussion will also include the effect of plasma additives on MNF production. Results indicate the relative amounts of C60, C70 and MNF fullerenes are sensitive to variables in the plasma environment.
COLLOIDAL DISPERSIONS OF POLY-(METHYL METHACRYLATE/n-BUTYL ACRYLATE)
Amy Rutland*, Shelley Huskey*, Laura G. Kolibal, Anuradha Singh, and Marek W. Urban, University of Southern Mississippi, Hattiesburg, MS 39406
These studies focus on synthesis and film formation of colloidal dispersions containing stimuli-responsive components. In order to gain a fundamental understanding of these processes the influence of bio-active dispersing agents on colloidal film formation is examined. In this study, a copolymer of poly-(methyl methacrylate/n-butyl acrylate) was synthesized using an emulsion polymerization process. Utilizing sodium dioctyl sulfosuccinate (SDOSS) as surfactant, the effect of particle size and surfactant concentration was examined. These studies indicate that larger colloidal particles enhance the mobility of surfactant migration within the film matrix, which is attributed to decreased surfactant coverage around the larger colloidal particles and freer surfactant within the film matrix. The influence of bio-active phospholipids was also examined. These studies show that the presence of mixed micellar structures under various stimuli such as pH, ionic strength, and temperature lead to the controlled migration of individual dispersing agents to the film-air or film-substrate interfaces. This work was supported primarily by the RET program of the National Science Foundation under Award Number EEC-0602032.
ANION BINDING BY TREN-BASED AMINE LIGAND
Katrina Battle*, Md. Alamgir Hossain, and Ashton T. Hamme, Jackson State University, Jackson, MS 39217
Design and synthesis of anion receptors are of current focus of research because of the important role played by anions in both environment and life. Among the various anion ligands, polyamines are widely used for anion binding. The polyamines, after protonation, are capable of interacting with anions through hydrogen bonding. Tren-based amines are converted into the protonated amines in the form of p-toluene sulfonate salts, which are then used for binding of inorganic anions in solution by NMR titration methods. Anion complexes are obtained by the reaction of the ligands and the mineral acid. The details of the synthesis, NMR binding and crystal structures will be will be presented in this poster.
SYNTHESIS AND CHARACTERIZATION OF FUNCTIONAL IRON OXIDE FERROFLUIDS
David Heaps*, Erin Fortenberry, Curtis Coumbe, Steven Stevenson, and Paige Phillips, University of Southern Mississippi, Hattiesburg, MS 39406
This project addresses the need to develop functional agents, which can provide an immediate, local action (e.g. catalytic) when applied to the target system and allow for subsequent easy and complete removal of the agent on command. By using a core-shell ferrofluid--comprised of a superparamagnetic magnetite particle core and a functionalized active agent shell--agent removal can be facilitated via a simple bar magnet extraction procedure. Magnetite is a preferred magnetic core material due to its low toxicity and well-characterized magnetic behavior. Initial work in the synthesis and characterization of magnetite core-shell structures is described. In these systems, magnetite base ferrofluid physical properties (e.g. particle size)--characterized by optical, TEM and light-scattering techniques--are found to be strongly dependent on the method of ferrofluid preparation. Recent shell-forming techniques include coating the magnetite cores with a thin, silica layer, which can be readily derivatized with application-specific functional groups.
ABSENCE OF AUTOACCELERATION IN AROMATIC SULFONYL AZIDES AS FREE-RADICAL INITIATORS FOR PHOTOPOLYMERIZATION
Bridget Confait*, Nicole Mackey, Emery Shier, Charles Hoyle, and Paige Phillips, University of Southern Mississippi, Hattiesburg, MS 39406
The decomposition reaction of aromatic sulfonyl azides when irradiated with UV light produces nitrogen gas and the nitrene diradical. The nitrene diradical produced is shown to initiate the free-radical photopolymerization of acrylates, such as hexanediol diacrylate (HDDA). Typically, the rates of photopolymerization in acrylate systems are characterized by an autoacceleration period where there is an increase in photopolymerization rate as the movement of the growing radical chains becomes restricted. The rates of photopolymerization of HDDA using sulfonyl azide initiators--as determined by photo-dsc analysis--do not exhibit the characteristic autoacceleration period typical of these systems.
VOMM SYNTHESIS AND WATERBORNE INDUSTRIAL COATINGS
Glenn Dale*, Jamie Morrison*, David E. Delatte, Lori Howell, and James W. Rawlins, University of Southern Mississippi, Hattiesburg, MS 39406
Vegetable oils are triglyceride esters of fatty acids extracted as a raw material precursors from plants. Newly developed vegetable oil derivatives, termed vegetable oil macromonomers (VOMMs), have been designed and synthesized for use as comonomers in emulsion polymerization. VOMMs are being incorporated and developed for environmentally responsible, decorative, and protective coatings that do not require the use of cosolvents for efficient film formation. However, these VOMMs possess limited hydrolytic resistance as they contain labile ester groups, inherently susceptible to hydrolysis. Ester-free VOMMs were designed to achieve improved hydrolytic resistance. Several new reaction methodologies were conducted at various temperatures and the progress was monitored continuously via infrared spectroscopy. Meanwhile, industrial coatings were formulated using commercial latexes to serve as controls for evaluating VOMM-based emulsions in industrial coating applications. Three styrene-acrylic latexes and two alkyd dispersions were formulated into industrial coatings in combination with hexamethoxymethylmelamine crosslinker and evaluated via ASTM test methods. This work was supported primarily by the RET program of the National Science Foundation under Award Number EEC-0602032.
PERSISTENCE: COMPLETION OF STEM DEGREES AT AN HBCU
Jeffrey Zubkowski*, Shonda Allen, Loria Brown, Linda Channell, and Donna Lander, Jackson State University, Jackson, MS 39217
Persistence: To go on resolutely or stubbornly in xpite of opposition, importunity or warning. The NSF has reported an increase in degrees earned by underrepresented groups in the STEM disciplines. The relationship between student success and support programs was examined. Specifically, the relationship between program interaction, stipend, research opportunities, development activities and student persistance in obtaining a baccalaureate degree are discussed.
STUDY OF CHEMICAL COMPOSITIONS OF A NIGERIAN EDIBLE PLANT VENONIA AMYGDALINA (VA)
Xuan Luo, Daniel Oyugi, Ernest B. Izevbigie, and Ken S. Lee, Jackson State University, Jackson, MS 39217
Breast cancer is the most commonly diagnosed cancer in women. One out of every eight women will be diagnosed with cancer in her lifetime. Numerous drugs have helped prolong the expansion of cancer but an effective drug has significantly yielded the progress in the fight against cancer. Among these drugs are plant-derived products which are considered potentially effective for their use as chemotherapeutic and chemopreventive agents. One such plant, Vernonia amygdalina (VA) leaf extract, has been reported to be potentially potent to human breast tumor cell line MCF-7. We have used two organic solvents, 100% EtOAc and 85% EtOH to extract active organic components from VA leaf. The experiment data reveals that the condensate of 85% EtOH shows higher potent activity than that of EtOAc. At the same time, using 85% EtOH to extract just requires shorter period to extract than EtOAc. Silicon gel will be used to absorb the condensate in the gradient elution (the solvent system is 100% hexane, 3 : 1=hexane : EtOAc, 1 : 1=hexane : EtOAc)=, and 100% EtOAc) to separate the condensate into four fractions. From previous experiment of ethyl acetate extract with gradient elution and column chromatograph gave four fractions and fourth one shows best activity toward MCF-7 cell. Using TLC for analyzing fourth fraction further, mixture of [CH.sub.2][Cl.sub.2] : MeOH (8:2), can be separated into two parts. The result of analysis and separation will be discussed in detail.
SYNTHESIS AND CHARACTERIZATION OF PHENOLIC RESIN/OCTA (AMINOPHENYL-[T.sub.8]-POLYHEDRAL OLIGOMERIC SILSEQUIOXANE (POSS) HYBRID NANOCOMPOSITES
Sang Ho Lee (1*), Yudong Zhang (1), Mitra Yoonessi (2), Hossein Toghiani (1), and Charles U. Pittman, Jr. (1), (1) Mississippi State University, Mississippi State, MS 39762 and (2) Air Force Research Laboratory, Wright-Patterson AFB, OH 45433
Nanocomposites composed of nano-sized dispersed phases blended into organic polymeric resins have been developed extensively in the past decade. Polyhedral oligomeric silsesquioxanes (POSS) have been employed as a curing hardener for resins in nanomaterial science. Octa(aminophenyl)-[T.sub.8]-polyhedral silsesquioxane, (N[H.sub.2])[.sub.8]([C.sub.6][H.sub.4])[.sub.8][O.sub.12][Si.sub.8], 1, is an octafunctional-[T.sub.8]-POSS containing eight aniline-like amino groups, one on each corner silicon atom. 1 was synthesized by an improved two-step reaction sequence; nitration (HN[O.sub.3]) and reduction (HCOOH/[Et.sub.3]N). The amino functional groups of 1 can form chemical bonds or hydrogen-bonds to appropriate matrix polymers or resins. Various resole phenolic resin/1 nanocomposites (0, 1, 3, 6, and 12 wt% 1) were prepared. The intermolecular interactions in these nanocomposites were probed by FT-IR. The micro-morphology and aggregation state of 1 were investigated using SEM, TEM, and WAXD studies. Thermal and mechanical properties and thermal stabilities of these composites were examined by DMTA and TGA, respectively. Moreover, surface extractions by THF removed only a portion of the 1 in the surface regions based on X-EDS analyses for Si, suggesting that a portion of 1 might chemically bond into the phenolic resin matrix during the cure. As the loading of 1 increased, the content of 1 at specific surface locations gradually tends to increase and confirmed excellent dispersion of 1 in the micron size-scale at all locations.
COMPARISON OF [C.sup.13]-NMR CHEMICAL SHIFTS WITH QUANTUM CALCULATIONS
Cardell Givens*, Joseph A. Bentley, and Alline P. Somlai, Delta State University, Cleveland, MS 38733
The Carbon-13 Nuclear Magnetic Resonance ([C.sup.13]-NMR) spectra were collected on a 300 MHz ECX-JEOL spectrometer for four constitutional isomers: n-butyl bromide, isobutyl bromide, t-butyl bromide and 2-butyl bromide. The [C.sup.13]-NMR chemical shifts were calculated by both ChemDraw and the computational chemistry program SPARTAN using the STO-3G, 3-21G(*), 6-31G(D) and 6-31G** basis sets. Although neither calculation gives extremely good agreement with the experiment, the methods are comparable and give fairly good estimations of the experimental chemical shifts. The energies calculated using SPARTAN are also presented.
SOLUBILITY INVESTIGATIONS OF (K+, Na+, Cs+)-NO3--OH-H20 SYSTEMS
Caleb Tash*, Laura T. Smith, Rebecca K. Toghiani, and Jeff S. Lindner, Mississippi State University, Mississippi State 39762
The thermodynamic behavior of Cs+ and K+ ions in solution is of interest when modeling high-level waste separation processes and in the establishment of operational envelopes for waste processing. For thermodynamic modeling of Department of Energy legacy nuclear wastes, the Environmental Simulation Program (ESP, OLI Systems, Inc.) is used. The aqueous electrolyte model allows estimation of the solid-liquid equilibria of waste constituents and evaluation of physical properties including densities, aqueous phase viscosity, pH, and phase volume fractions. Work in this laboratory has been on-going since 1997 and has focused on experimental measurement of the solubility for major sodium salts present in the waste. These include NaNO3, NaNO2, Na2SO4, and Na2CO3.1H20, and more complex double salts including Na7F(PO4)2.19H20, Na6(SO4)2CO3, and Na3FSO4. The results of this effort have been compiled into a double salt database (V7DBLSLT) which is in use throughout the DOE complex. Current available databases contain limited information, however, on the solubility of potassium nitrate and cesium nitrate in caustic solutions under high ionic strength conditions. An initial comparison of available literature data for these systems with ESP predictions revealed disagreement. Thus, solubility measurements for two systems were undertaken: KNO3/NaNO3 and CsNO3/NaNO3. Experiments were conducted at two temperatures (25 and 50 ,,aC) in water, 1m and 3m NaOH. Each sample was monitored weekly to establish attainment of equilibrium. A comparison of preliminary experimental data with ESP predictions indicates that the ESP model overestimates the potassium and cesium ion concentrations. Model predictions, experimental results, and comparisons will be discussed.
MECHANISTIC STUDIES OF FREE RADICAL AZIDATION
Douglas S. Masterson and Jessica Shackleford*, University of Southern Mississippi, Hattiesburg, MS 39406
Carbon-Nitrogen bonds can be formed through free radical azidation using Sulfonyl Azides, however the mechanism is still questionable as to which Nitrogen acts as the free radical trap. Through our research, we have been able to label the [gamma]? Nitrogen of the Sulfonyl Azide by treating Sulfonyl Hydrazide with Nitrogen-15 labeled Sodium Nitrite in HCl to produce an average 93% yield of N15 labeled Sulfonyl Azide. Our first primary reaction treated Ethyl Iodoacetate and Octene with Sulfonyl Azide to produce the product Ethyl 4-Azidodecanoate, while our second primary reaction treated Ethyl Iodoacetate and Methylene Cyclohexane with Sulfonyl Azide to produce Ethyl 3-(1-Azidocyclohexyl)propanoate. Both products were hydrogenated at a later time so that only the free radical trap Nitrogen remained. Each reaction was repeated multiple times, and in all reactions the labeled [gamma]? Nitrogen always served as the free radical trap. The data gained from this study could be applied to making Nitrogen-15 labeled Amino Acids from simple materials.
PHOTOCHEMICAL CLEAVAGE OF DNA WITH NITROGEN ONIUM SALTS
Amanda Mayo*, Andrew S. Olinger, and Wolfgang Kramer, Millsaps College, Jackson, MS 39210
Quantitative photochemical DNA cleaving studies with nitrogen onium salts were performed using potential DNA intercalators based on the quinoline, isoquinoline and phenanthridine skeletons. The efficiency was analyzed by gel electrophoresis.
INVESTIGATION OF THE PERFORMANCE OF COATINGS FORMULATED WITH THE REACTIVE DILUENT TETRA(2,7-OCTADIENYL) TITANATE
Rhonda Robertson (1*), Crystal Smith (2*), Alp Alidedeoglu (2), Kevin Davis (2), James W. Rawlins (2), and Sarah E. Morgan (2), (1) Jones County Junior College, Ellisville, MS 39437 and (2) University of Southern Mississippi, Hattiesburg, MS 39406
Volatile organic compounds (VOCs), traditionally used in the formulation of paints and coatings, are the subject of environmental concern and legislation mandating reduction of their use. There is currently intense research interest in developing coatings with no or low solvent emissions. One method of reducing VOCs is through incorporation of reactive diluents, which replace solvents in the formulation but do not evaporate upon application, but rather undergo crosslinking reactions in the resin on exposure to oxygen. A new reactive diluent, tetra(2,7-octadienyl) titanate, was synthesized through ether exchange reaction between 2,7-octadienol and tetra(ethyl) titanate, evidenced by 1H-NMR, 13C-NMR, HPLC and FTIR. The resulting reactive diluent was formulated with soy-based and linseed-based alkyd resins, both with and without added metal dryers, at weight percentages ranging from 10 to 30%. Films were prepared from the formulations and their properties evaluated in comparison to controls, including hardness, adhesion, impact strength, cure, viscosity, optical properties and chemical resistance. Fast drying, low VOC, low viscosity formulations were obtained utilizing the reactive diluent. Films prepared from reactive diluent formulations exhibited exceptionally fast dry times and superior hardness in comparison to controls. Adhesion properties and impact properties were somewhat reduced, while other tested properties were equivalent to controls.
DEVELOPMENT OF INHIBITORS OF AGMATINASE: SYNTHESIS OF AGMATINE ANALOGUES, PIPERAZINECARBOXAMIDINE
Eva A. Clark *, Vyvyca Jones, and Ken S. Lee, Jackson State University, Jackson, MS 39217
Agmatine is an endogenous amine with four carbon chain to a guanidine group that is synthesized in the brain following decarboxylation of L-arginine by arginine decarboxylase. Recent studies indicate that agmatine can have several important biochemical effects in humans, ranging from effects on the central nervous system to cell proliferation in cancer and viral replication. In a series of experiments with rat pups, agmatine showed the effect reducing the brain damage in hypoxia-ischemia and the production of nitric oxide when it was added. Agmatinase catalyses the hydrolysis of agmatine to putrescine and urea and is a major target for drug action and development. Therefore we are looking for the way to regulate the level of agmatine in the brain. One of methods we are interested in is to modify the structure of agmatine, which can inhibit degradation of agamatine by blocking the agmatinase. From the previous study including QSAR, one of agmatine analogues, 3-aminopropylguanidine showed the promise. And the study suggests the piperazine analogues of agmatine would have the properties we are looking for. As a second phase of study we attempted to synthesize piperazine-carboxamidine and 2-methylpiperazinecarboxamidine. They were prepared by the reactions between cyanamide and corresponding diamines including piperazine derivatives like piperazine and 2-methylpiperazine. Piperazinecarboxamidine were synthesized as described and its spectroscopic data including [1.sup.H], [13.sup.C] NMR and IR were taken.
TREATMENT OF SAWDUST WITH IONIC LIQUID: SEPARATION OF CELLULOSIC MATERIAL FROM LIGNIN
Teresa Demeritte*, Jeffrey Thorn, and Ken S. Lee, Jackson State University, Jackson, Mississippi 39217
Green chemistry has received great attention from chemists and environmentalists since it reduces the usage of hazardous materials in the chemical process. One of developments in green chemistry is to substitute the volatile organic solvents with ionic liquids to reduce the VOC. It is known that some ionic liquids can dissolve cellulose in higher temperature and the phase of cellulose can be changed easily. Therefore we have attempted to separate the cellulosic material from lignin in sawdust of soft pine wood. Ionic liquid, 1-n-butyl-3-methylimidazolium chloride ([[C.sub.4]mim][.sup.+][Cl.sup.-]), was prepared from n-butyl chloride and 1-methylimidazole and purified. Its preparation was confirmed by [1.sup.H] and [13.sup.C] NMR and it was mixed with sawdust with various ratios for finding better condition. Sawdust was separated based on the mesh number and they were mixed with ionic liquid separately. Mixture was stirred at elevated temperature for overnight and it filtered under the pressure. Addition of water into the filtrate gave brown colloidal solution. The brown powder was separated and its chemical analysis was attempted for identifying cellulose.
SYNTHESIS AND CHARACTERIZATION OF PH-RESPONSIVE POLYMER BRUSHES
Shijie Ding* and Keisha B. Walters, Mississippi State University, Mississippi State, MS 39762
A well-defined series of polyamine brushes have been synthesized via surface-confined atom transfer radical polymerization (ATRP) on silicon (Si) wafers. These polymer brushes were polymerized from initiator reacted onto the terminal groups of self-assembled monolayers (SAMs). The effect of solvent, monomer concentration, ligand and initiator on the polymerization success was examined. The chemical composition of the samples at each reaction step was characterized using FTIR and x-ray photoelectron (XPS) spectroscopies and the thickness of the polymer layers was measured with ellipsometry. By changing the monomer, our goal is to synthesis a series of polyamines with varying tertiary amine functionalities. The tertiary amine pendant groups on these polymer brushes are bases and will therefore show changes in chain extension and contraction with changes in pH. The pH-responsive behavior of polymer brush thickness will be measured using in-situ ellipsometry.
INTERCALATIONS OF ORGANIC MOLECULES INTO CLAY MIMICS
Alicia M. Beatty* and Austin Pickett, Mississippi State University, Mississippi State, MS 39762
Several organic molecules will be intercalated into the interlayer of a clay mimic constructed of 3,5-Pyridinedicarboxyl-ic acid and a diamine. The two diamines used are 1,10 Diaminodecane and 1,12 Diaminododecane. The clay mimic crystals were sonicated in a solution of the individual organic molecules, most of which contain polar groups, and tests were taken of the sonicates to determine if intercalation occurred. The three tests used were Differential Scanning Calorimeter (DSC), Thermogravimetric Analysis (TGA), and NMR. Results for several guest molecules will be discussed, including results for different polar organic molecules. Synthesis of an amine-containing ether to replace the diamines used will also be discussed. The presence of oxygen atoms in the carbon chain will hopefully provide more possible hydrogen bonding sites to secure the intercalated guests.
IDENTIFICATION OF PEPTIDES THAT BIND TO ESTROGEN RESPONSE ELEMENTS: USING PEPTIDE PHAGE DISPLAY LIBRARY
Matthewos Eshete*, Zakary Ndegwa, and Matthewos Eshete*, Mississippi Valley State University, Itta Bena, MS 38941
Short peptides can mimic estrogen receptor proteins and bind to the same site on the DNA as the proteins do. In this research peptide phage display library has been utilized to select peptides which bind to estrogen response elements. The phage display library used to select peptides against the target Estrogen response elements were random 15-mer phage display library and f88-4/Cys6 phage display library. Human pS2 ERE and Xenopus Vitelloginin A2 ERE were used as target DNA molecules. The first round of selection has been performed using 15-mer phage display library and f88-4/Cys6 phage display library against Xenopus Vitelloginin A2 ERE and Human pS2 ERE. From 15-mer phage display library 25 phage clone were selected using Xenopus vitelloginin A2 ERE as a target molecule and 19 phage clones were selected using Human pS2 ERE. On the other hand 15 phage clones were selected from the f88-4/Cys6 phage display library against Xenopus vitelloginin A2 ERE as a target molecule and 30 phage clones were selected using Human pS2 ERE as a target molecule. Each of the phage clones selected from both phage display library corresponds to the binder peptide sequences. However only the peptides selected at the last or 4th round would be sequenced to get the corresponding binder peptides. The progressive selection at the different round would tell us the selectivity and specificity of binding to the target molecule.
PRODUCTION OF RARE-EARTH METALLIC NITRIDE FULLERENES
Corey Thompson*, Curtis Coumbe, Mary Mackey, Paige Phillips, Howard Louie Coumbe, and Steven Stevenson, University of Southern Mississippi, Hattiesburg, MS 39406
Metallic Nitride Fullerenes (MNFs) containing rare-earth metal atoms are being developed as new pharmaceuticals. MNFs and application areas include Gd3N@C80 (MRI contrast agents), Lu3N@C80 (X-Ray contrast agents), and Ho3N@C80 (radiopharmaceuticals). Hence, the synthesis of these rare-earth MNFs is of great importance. Results indicate that rare-earth MNFs have lower yields than Sc3N@C80. The relative yields for the rare-earth series are Lu3N@C80 > Ho3N@C80 > Gd3N@C80.
MISCIBILITY STUDIES OF SOLUTION BLENDED POLYPHENYLSULFONE AND POLYPHENYLENE
Camille Short*, Paul J. Jones, and Sarah E. Morgan, University of Southern Mississippi, Hattiesburg, MS 39406
The goal of this research was to determine optimum film formation conditions for blends of polyphenylsulfone and polyphenylene and to evaluate their miscibility via optical microscopy and differential scanning calorimetry (DSC) techniques. Film formation factors evaluated include temperature of solvation and polymer concentration. Polymer powders were dissolved in 1-methyl-2-pyrrolidinone (NMP) at elevated temperatures. Solution temperature was optimized to avoid polymer degradation. Solutions were cast on glass plates and placed in a vacuum oven for overnight drying, and then placed in a convection oven to remove any remaining solvent. The cast films and unmodified polymer powders were analyzed by DSC. DSC results indicate that the blends are miscible over the concentration and temperature range evaluated.
INTERCALATION OF THE SN[I.sub.2] LAYERED PEROVSKITE INORGANIC-ORGANIC HYBRIDS
Nilantha Bandara and Alicia M. Beatty*, Mississippi State University, Mississippi State, MS 39762
Inorganic-organic hybrid perovskites have gained much attention over the past years due to their unique electronic and optical properties. Currently we are interested in making layered perovskites using Sn[I.sub.2] with primary and diammine organic-components, in order to test their ability to intercalate guest molecules. In the past, small molecules have been incorporated into the lattice by crystallization, and we are investigating the ability to remove and reincorporate these guests into the solid framework by both sonication and re-dissolving methods. The products will be characterized by single crystal X-ray diffraction, powder X-ray (PXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), IR and melting point analysis.
PREPARATION AND TREATMENT OF HANFORD TANK WASTE SLUDGE
Timothy Ruff*, L. T. Smith, Rebecca K. Toghiani, Dave C. Swalm, and Jeff S. Lindner, Mississippi State University, Mississippi State, MS 39762
The 53 million gallons (240,000 tons) of nuclear waste stored at the Hanford site comprises approximately 60% of the nation's legacy nuclear waste. Previously, processing of the saltcake phases of tank wastes dominated disposal efforts at Hanford. Interest is now being directed at the processing and pretreatment of the sludge phases of the waste. These sludges consisting of complex combinations of insoluble metal compounds present many challenges. This presentation deals with experimentation around possible pretreatment strategies for the complex sludge phases of the Hanford tank waste. First, an "average" sludge composition was established from statistical analysis of tank inventories. Previous work has involved preparation of simulant sludge from the Savannah River Site (SRS). The recipe for SRS waste sludge will be modified for use in preparation of the Hanford simulant sludges. Proposed pretreatment strategies involving caustic leaching and washing of sludges are also discussed as well as the performance of washing and leaching. Certain aspects of aluminum chemistry have also been investigated as a part of this work and are discussed, including solubilities of common aluminum species found in Hanford tank sludge as well as transition between those species.
3D-QSAR ANALYSIS OF FARNESYLTRANSFERASE INHIBITION FOR ANTIMALARIAL DIAMINOBENZOPHENONES
Shawna Clark (1*), Aihua Xie (2), and Robert J. Doerksen (2), Tougaloo College, Tougaloo, MS 39174 and University of Mississippi, Oxford, MS 38677
This project focuses on a quantitative structure-activity relationship (QSAR) investigation of a series of 2,5-diaminobenzophenone farnesyltransferase inhibitors developed by Schlitzer et al. as a new class of antimalarial compounds, in order to gain understanding and as a step toward developing a rational strategy for further lead optimization. 3D-QSAR methods (CoMFA and CoMSIA) were used to study a series of compounds, including 37 N-(4-tolyacetylamino-3-benzoylphenyl)-3-arylfurylacrylic acid amides, 24 N-(4-acylamino-3-benzoylphenyl)-3-[5-(4-nitropheyl)-2-furyl]acrylic acid amides, 14 N-(4-acylamino-3-benzoylphenyl)-4--nitrocinnamic acid amides, 8 N-(4-aminoacylamino-benzoylphenyl)-3-[5-(4-nitrophenyl)-2-furyl] acrylic acid amides, and 8 5-arylacryloylaminobenzophenones. Four 3D-QSAR models were built: three CoMFA models composed of steric and electrostatic fields, and one CoMSIA model containing only a hydrophobic field. The models prepared were not of high statistical quality but the resulting field contours combined with other drug design technology still can provide insights for lead optimization.
PRODUCTION OF GREEN DIESEL THROUGH CATALYTIC CRACKING OF PHOSPHOLIPIDS
Stephen Dufreche (1*), Rafael Hernandez (1), Todd French (1), Mark G White (1), Mark E. Zappi (2), Earl Alley (1), and Bill Holmes (1), (1) Mississippi State University, MS 39762 and (2) University of Louisiana, Lafayette, LA 70504
The paper will describe results of cracking phospholipids with triflic acid (super acid) to determine reaction mechanisms and product composition of Green Diesel. This fuel would be chemically identical to conventional diesel fuel, but derived from a clean renewable feedstock. The results will be used to assist in the synthesis of heterogeneous catalysts better suited for large-scale production. The paper also will cover the basic theory behind cracking of phospholipids through acid catalysis as well as a description and economics of potential feedstock sources capable of supplying the U.S. with large amounts of green diesel.
SYNTHESIS OF A SELF-ASSEMBLED, NANOSTRUCTURED POLYMER FOR ORGANIC PHOTOVOLTAIC (OPV) CELLS
LaTisha Wilson (1*), Dolly Batra (2), and Millicent Firestone (2), (1) Tougaloo College, Tougaloo, MS 39174 and (2) Argonne National Laboratory; Argonne, Illinois 60439
Organic photovoltaic cells (OPVs) differ from conventional silicon-based photovoltaics (PVs) because they offer increased flexibility and cheaper costs; however, the efficiency of OPVs (3-5%) is considerably lower than that of traditional, inorganic PVs. The development of nanostructured, organic polymers where electron transport can be easily controlled offers an approach for fabricating a more efficient OPV framework. With this project the synthesis of a photopolymerizable ionic liquid monomer was targeted and it was hypothesized that polymerization would lead to a nanostructured poly(ionic liquid) incorporating both an electron accepting imidazolium group and an electron donating thiophene group. Further studies will involve studying the change in self-assembly caused by thiophene, and how transport properties of the resulting polymer affect the efficiency in an OPV material. This work was performed under the auspices of the Office of Basic Energy Sciences, Division of Materials Sciences, United States Department of Energy, under contract No. DE-AC02-06CH11357.
INVESTIGATING THE EFFECT OF SODIUM CHLORIDE CONCENTRATION ON COMPLEX COACERVATE FORMATION WITHIN A CONCENTRATED REGIME
Lisa Fike*, Nicole McWright*, and Robert Lochhead, University of Southern Mississippi, Hattiesburg, MS 39406
Shampoos comprise amphipathic molecules called surfactants that self assemble into nano-scale micelles. The micelles are responsible for the cleaning action of shampoos. In conditioning shampoos, polymers interact with the surfactants. The dilution of shampoo, while washing hair, causes the cationic polymer and the anionic surfactant to form complex coacervates that can phase separate from the solution and, during rinsing, this polymer-surfactant complex is deposited on the hair as a conditioner. There are many possible self-assembled structures that can form from the surfactants and the polymers, and the shampoo formulator has to find the best formula. High-throughput screening allows the examination of hund reds of compositions each day. Thus, our high-throughput method using a liquid handler allows approximately 200 different concentrations to be performed in about 45 minutes. In our research, Polyquatemium-10 (JR 30M) was used as the cationic polymer and sodium lauryl ether sulfate(SLES) as the anionic surfactant. Sodium chloride (NaCl) is added to shampoos to increase the viscosity, but salts can also influence the micelle structure, the poly ion conformation and the nature of the coacervate. Our motivation in doing this experiment was to investigate how sodium chloride affects this interactive system. Our results show that as the concentration of NaCl increased, the amount of coacervate formed decreased in the 'ion-exchange' region but increased in the large micelle region.
Hunter Henry Ballroom A
8:00 NANO-ENCAPSULATION OF TRACE METAL IMPURITIES IN BIODIESEL
Shampa Aich,* Keisha B. Walters, and Adrienne Minerick, Mississippi State University, Mississippi State, MS 39762
Biodiesel, an alternative diesel fuel, has environmental benefits and can be synthesized from renewable biological sources such as vegetable and seed oils, animal fats, and sewage sludge. Depending on the raw materials, trace metal contaminants are present in the processing streams including Cu, Mn, Pb, Zn, Co, Fe, and B. These metal impurities can have significant adverse effects, such as biofuel fouling or degradation during long-term storage. Therefore, our research objective is to determine the feasibility of growing inert silica shells around the trace metal particulates via core-shell nanotechnology. The resulting inert nanoparticles may be removed by gravitational settling, filtration, or magnetic / electrophoretic separations. Silica, the coating material, is chemically inert, optically transparent, and produces concentrated dispersions by preventing coagulation. In the literature, nanoencapsulation of colloidal nanoparticles has included metals (Au, Ag, Fe/Fe2O3), semiconductors (CdS, ZnS, CdSe/ZnSe), polymers (polystyrene, polydimethylsiloxane), and inorganic oxides (boehmite rods, gibbsite platelets). However, encapsulation of the two most important metal impurities in sewage sludge derived biodiesel, Cu and Pb, has not occurred. Nanoencapsulation of colloidal Cu nanoparticles with silica shells is investigated. The reaction sequence will be perfected using clean stock solutions of copper nanoparticles (15-20 nm) functionalized with polyvinylpyrrolidone (PVP) and sodium dodecylbenzene sulphonate (SDBS). PVP and SDBS function as linkers and stabilizers prior to encapsulation with the shell-building material, tetraethoxysilane (TEOS). Aqueous ammonia and ethanol are used as the catalyst and solvent respectively. The resulting nanoparticle metal core--silica shell samples are then characterized with TEM, SEM, FTIR, and UV-vis spectroscopy to assess average particle diameter, silica shell thickness, and optical properties. As this work progresses, the reaction sequences will be adapted to biodiesel samples.
8:15 A MICROFLUIDIC STUDY OF TRANSIENT INTERFACIAL PHENOMENA IN MISCIBLE AND PARTIALLY MISCIBLE SYSTEMS
Gloria Viner* and John A. Pojman, University of Southern Mississippi, Hattiesburg, MS 39406
This study focused on the unusual interfacial phenomena of different miscible and partially miscible systems such as isobutyric acid and water. Previously, we had studied systems such as isobutyric acid and water with a spinning drop tensiometer; we wanted to see how different miscible systems that we could not previously studied, such as ethanol/water, and some systems that we have studied would behave in a system that allows the components to interact without any rotating forces. The microfluidic approach allowed us to observe the Rayleigh-Plateau instability without mixing of the fluids.
8:30 INTERCALATIONS OF LEWIS BASES INTO INORGANIC/ORGANIC HYBRID CLAY MIMICS
Greg Hogan* and Alicia M. Beatty, Mississippi State University, Mississippi State, MS 39759
Clays intercalate small molecules or ions between metal oxide layers. Our group makes hydrogen-bonded layered material using coordination complexes and organic amines. The coordination complexes contain axial water ligands, and we wish to determine if these ligands can be replaced by Lewis bases while retaining the hydrogen-bonded layer structure. A series of reactions were set up in which the layered solid is exposed to an excess of a variety of Lewis bases through sonication in hexanes. Characterization of these products was done by IR, DSC, powder XRD, and TGA. Using the latter technique we observed significant differences in weight loss in starting material versus products. These weight losses corresponded to replacement of water with the Lewis bases. These and other results will be discussed.
8:45 POST TRANSLATIONAL REGULATION OF PROLYLCARBOXYPEPTIDASE (PRCP) IN CHINESE HAMSTER OVARY (CHO) CELLS
Mubina Isani* and Shariat Madar, University of Mississippi, University, MS 38677
PRCP involves in the conversion of angiotensin II (Ang II, a potent vasoconstrictor) to angiotensin 1-7 and conversion of bradykinin (BK, a vasodilator) to form des Arg9 bradykinin. PRCP converts PK to plasma kallikrein when the high molecular weight kininogen (HK) combines with PK, forming the HK-PK complex that binds to human umbilical vein endothelial cells (HUVEC) membranes. Formed kallikrein then liberates BK from HK, which leads to vasodilation. This physiological function is mediated by the BK type 2 receptor in the G protein-coupled receptor family. The balance between BK production and Ang II inactivation is important for wound healing, angiogenesis and high blood pressure regulation. Our goal was to determine the post translational regulation of PRCP in CHO cells. CHO cells were transfected with full-length PRCP under the control of a CMV promoter and rPRCP was expressed as a fusion protein with C-terminal enhanced green fluorescent protein (EGFP). The binding of biotinylated HK to wild type CHO cells was time dependent, dose dependent, saturable and reversible. The PRCP-induced PK activation was similar on wild type and PRCP-transfected CHO cells. PRCP inhibitor, Z-Pro-Prolinal did not block PK activation on wild type cells. In the future, we wish to further characterize the molecular trafficking of PRCP in PRCP-transfected CHO cells. In sum, these findings will be an important advance in our knowledge of PRCP function.
9:00 AN ELECTROCHEMICAL STUDY OF A SCHIFF BASE COMPLEX OF VANADIUM(V) AND ITS INTERACTIONS WITH CALF THYMUS DNA IN DMSO- A SEARCH FOR NEW ANTI-CANCER AGENT
Suman Parajuli (1), Gabriel R. Harewood (2), Kerry-Ann Green (2), Paul T. Maragh (2), Tara P. Dasgupta (2), Wujian Maio (1*), and Alvin A. Holder (1*), (1) University of Southern Mississippi, Hattiesburg, MS 39406 and (2) University of the West Indies, Mona, Jamaica
A new vanadium(V) complex with an azo Schiff base as ligand was synthesized and characterized. Cyclic voltammetric studies were carried out on the complex in de-aerated DMSO solution containing 0.10 M TBAP at a glassy carbon electrode. Preliminary data showed that, two reduction waves, located at -0.35 V and -0.51 V vs. Ag/AgCl, were observed at a scan rate of 50 mV/s, which are probably associated with of reductions of V(V) to V(IV), and V(IV) to V(III), respectively. No re-oxidation corresponding to the above two reduction waves was observed, suggesting that the reduction of the metal center is irreversible. An irreversible oxidation wave, located at 0.76 V vs. Ag/AgCl, was observed, which could be attributed to the ligand oxidation. The effectiveness of this complex in binding to calf thymus DNA has also been carried out through cyclic voltammetry with "DNA-complex titration method". The results of the findings will be presented.
9:15 SEPARATION AND ISOLATION OF NEW METALLIC NITRIDE FULLERENES
Mary Mackey*, Curtis Coumbe, and Steven Stevenson, University of Southern Mississippi, Hattiesburg, MS 39406
Recent work in our lab has led to the isolation of Sc3N@C68, Sc3N@78, and Sc3N@C80 Metallic Nitride Fullerenes (MNFs). However, there is a paucity of information on the existence of other MNFs (i.e. other carbon cages). Soot has been obtained from our electric-arc plasma nanomaterial generator. These soot extracts were then characterized by HPLC. The chromatograms for these samples indicate the presence of new peaks. We have identified and collected HPLC fractions and characterized them by MALDI-TOF mass spectrometry. Results also indicate candidate molecular formulas for these new species.
9:30 STUDIES OF ELECTROCHEMICALLY PREPARED ION-SELECTIVE MEMBRANES WITH SECM
Shijun Wang (1), Milka T. Neshkova (2), Wujian Miao (1*), (1) University of Southern Mississippi, Hattiesburg, MS 39406 and (2) Bulgarian Academy of Sciences, Sofia, Bulgaria
A semi-conductive Cu(II) ion-selective membrane of [Cu.sub.2-x]Se (x = 0.67) was electrochemically synthesized and deposited on the surface of a Pt-disk electrode. The potentiometric response of the membrane in the presence of diluted Cu(II) solutions was found to follow Nernstian behavior (29 mV [dec.sup.-1]) at room temperature. In order to investigate the mechanism of the ion-selective membrane, aqueous solutions of mM levels of CuS[O.sub.4], 1.0 M [CH.sub.3]CN, and 0.10 M LiCl[O.sub.4] were prepared and their electrochemical behavior was studied with cyclic voltammetry using macro- and micro- Pt electrodes. One electron-transfer reversible process between Cu(II) and Cu(I) was observed and the diffusion coefficient of Cu(II) under the present experiment conditions was determined. Scanning electrochemical microscopic (SECM) experiments were conducted with a Pt microelectrode as the tip and the membrane deposited on Pt as the substrate using above Cu(II)-C[H.sub.3]CN-LiCl[O.sub.4] solution as the electrolyte mediate. The open circuit potential changes of the membrane with the approaching of the tip held at the reduction potential of Cu(II) was monitored. Finally, a mechanism of the ion-selective membrane was proposed. Financial support through NSF-OISE-0535467 grant is gratefully acknowledged.
9:45 SCALABILITY ASSESSMENT OF THE SAFA TECHNIQUE FOR ISOLATING METALLIC NITRIDE FULLERENES
Curtis Coumbe (1*), Mary Mackey (1), Katie Carpenter (2), Paige Phillips (1), David Heaps (1), and Steven Stevenson (1), (1) University of Southern Mississippi, Hattiesburg, MS 39406 and (2) Mississippi University for Women, Columbus, MS 39701
Discovered and developed in our lab, a novel "Stir and Filter Approach" (SAFA) is currently under development as an alternative separation method for isolating Metallic Nitride Fullerenes (MNFs) nanomaterials. With SAFA, the plasma soot extract is dissolved in xylene, and reactive aminosilica is added. The amino functionality on the silica support selectively binds to contaminant fullerenes (e.g. C60, C70) and classical metallofullerenes (e.g. Sc2@C84). The more chemically inert MNFs are more resistant to attack by the amino groups. Hence, the filtrate of the slurry is purified MNFs. Results indicate that the SAFA approach is a scalable method for isolating MNF nanomaterials.
10:15 SYNTHESIS OF INTERCALATIVE DNA CLEAVING REAGENTS
Wolfgang Kramer*, Bentley Woods Curry, Amanda Mayo, and Andrew S. Olinger, Millsaps College, Jackson, MS 39210
The design of a photoactivated DNA-cleaving reagent has to combine the actual cleaving functionality and the DNA-binding properties in the same molecule. We used a fragmentable N-O bond as the cleaving functionality that produces an alkoxy radical and an heteroaromatic radical cation. Intercalators such as ethidium bromide have been widely used to bind to DNA but the actual binding properties of a variety of synthesized derivatives have been poor. Carriers moieties like naphthalene diimides were attached to improve DNA binding.
10:30 BINDING STUDIES OF POTENTIAL DNA INTERCALATORS
Bentley Woods Curry*, Neha S. Solanki, Jonathan P. Giurintano, and Wolfgang H. Kramer, Millsaps. College, Jackson, MS 39210
The DNA binding properties of a series of potential DNA intercalators based on the quinoline, isoquinoline and phenanthridine skeleton have been tested. Fluorescence, UV/VIS, CD and viscometry studies show different binding behavior and suggest different binding modes.
10:45 KINETIC AND MECHANICAL ANALYSIS OF NANO-GOLD-THIOL-ENE COMPOSITE FILMS
Nicole Mackey*, Bridget Confait, Xiao Deng, Hui Zhou, Charles Hoyle, and Paige Phillips, University of Southern Mississippi, Hattiesburg, MS 39406
Well-dispersed gold nanoparticles in UV-cure thiol-ene films produces optically clear samples with interesting mechanical and kinetic properties. Characterization techniques used in assessing the mechanical properties of the composite films include DMA and bulk tack analysis, using a texture analyzer. DMA measurements indicate that the glass transition temperature (Tg) of the thiol-ene matrix remains relatively constant over the range of 0 to 10 % gold by weight. By monitoring film tack and hardness, samples are considered fully cured at the point where force measurements versus exposure time reached a constant value. Dynamic light scattering measurements are performed on casting solutions to monitor gold particle aggregation, and real-time IR measurements provide kinetic information regarding the rate of polymerization and extent of monomer conversion.
11:00 MECHANISM OF LIGHT-RESPONSIVE POLYMER-FULLERENE ADHESIVES
Xiao Deng*, Meredith Todd, Steven Stevenson, and Paige Phillips, University of Southern Mississippi, Hattiesburg, MS 39406
Triblock copolymers polystyrene-block-polybutadiene-block-polystyrene (SBS) and polystyrene-block-polyisoprene-block-polystyrene (SIS) are common rubber-based pressure sensitive adhesives (PSAs). When blended with C60 fullerenes, they produce easy-release systems, switching quickly from a tacky "on" state to an un-tacky "off" state when irradiated with visible light. Although, the idea of a radiation activated releasable adhesive for medical applications is not new, our system has distinct advantages: visible light radiation source instead of UV or e-beam, and the kinetics are accelerated by the presence of oxygen, unlike radical-based curing mechanisms which are depressed by oxygen. C60 fullerene is used as a sensitizer to generate singlet oxygen, which is believed to cause the fast and irreversible crosslinking of the polymer soft blocks and leads to the loss of adhesive properties in the resulting films. The participation of singlet oxygen in the mechanism was supported by the addition of accepted singlet oxygen generators, quenchers, and the use of inert oxygen-free environments.
11:15 PEEL AND TACK FORCE ANALYSIS OF RUBBER-BASED PRESSURE SENSITIVE ADHESIVES
Meredith Todd*, Xiao Deng, Steven Stevenson, and Paige Phillips, University of Southern Mississippi, Hattiesburg, MS 39406
Peel and tack forces are important mechanical quantities for adhesives, and the resulting force measurements can be correlated to sample properties such as hardness, cohesiveness, elasticity, adhesiveness, and viscosity. In these tests a material is subjected to a controlled force from which a deformation curve of the samples response is generated. Pressure sensitive adhesives (PSAs) have found wide application in tape and label manufacturing--for home, office, electric and medical purposes. Polystyrene-block-polybutadiene-block-polystyrene (SBS) and polystyrene-block-polyisoprene-block-polystyrene (SIS) copolymers are commonly applied rubber-based PSAs. These block copolymers have high cohesive strength due to the styrene composition and elastic portions derived from the unsaturated polybutadiene and polyisoprene. In this work, we report the peel and tack forces measured by Texture Analysis of these triblock polymers as pure samples and in blends with C60 fullerenes. The peel and tack forces of SIS and SBS polymers decrease dramatically when blended with C60 fullerene sensitizer and irradiated with visible light. C60--in the presence of visible light and molecular oxygen--generates singlet oxygen, which is likely responsible for the rapid and irreversible oxidative crosslinking of SIS and SBS polymers and subsequent loss in adhesion.
Hunter Henry Ballroom A
1:15 STUDY OF DEGRADATION OF ORGNAOPHOSPHORUS PESTICIDES IN NATURAL W ATERS AND TOXICITY OF TRANSFORMATION PRODUCTS
Xueheng Zhao*, Xiaoke Hu, and Huey-Min Hwang, Jackson State University, Jackson, MS 39217
Malathion and parathion are widely used organophosphate insecticides in the United States and throughout the world. Synthetic in origin, these organophosphates are persistent in the environment. It is of health concern about their transformation in the natural waters and the toxicity of pesticides and their transformation products to the environment. The objective of this study is to determine the effects of pH, photoirradiation and photosensitizer (riboflavin) on the degradation of these organophosphorus compounds. Our results showed that malathion was degraded slowly in water at pH = 3. It takes almost 3 months to degrade 50% of added marathion. The degradation rate was very fast in water at pH = 11. Over 50% malathion can be degraded within 10 minutes. Microorganisms in waters ehancedthe rate of parathion degradation and up to 50 % parathion was degraded in 10 days. Degradation products from malathion and parathion were identified by GC/MS and HPLC/MS, which included araoxon, aminoparathion, and 4-nitrophenol etc. Further degradation of paraoxon in natural water showed that it was transformed into 4-nitrophenol under aerobic condition. Cytotoxicity and genotoxicity tests of the studied pesticides and their transformation products, i.e. malaoxon, paraoxon, 4-nitrophenol, were carried out with human HaCaT cell and lymphocytes. Results show that cytotoxicity of transformation products such as malaoxon and paraoxon are increased compared to the parent pesticides. The exposure-induced DNA damage can not be found by Comet assay using the mentioned cells. This research was funded by the U.S. Department of the Army Research and Development grant # W912H2-04-2-0002 to JSU.
1:30 HAZARD ASSESSMENT OF DRINKING WATER IN THE DELTA
Terrica T. Ragland* and William Mahone, Mississippi Valley State University, Itta Bena, MS 38941
Organic contaminants in drinking water have long been a concern. These contaminants can include pesticides from agriculture run off and gasoline components from leaking underground storage tanks. The health effects involved include carcinogenic, mutanogenics, and teratogenic. In the current study, drinking water samples were acquired from various sources and were subjected to GCFID and GCMS analysis. Previous studies include UV-vis absorption spectra-photometric scanning and showed few contaminants at the ppm level. When detection levels were adjusted to the ppb level by modification of sample preparation methods, numerous trace organics began to appear. In this study, we are currently performing GCMS analysis to determine the identities of these contaminants. These contaminants, once identified are then subjected to MSDS screening using standard database. Using this information together with our data, we were able to make an assessment as to the hazard potential of these drinking water sources.
1:45 SELECTIVE PHOSPHATE ESTER CLEAVAGE IN PHOSPHOLIPIDS
Vijitha Mohan*, Laura Hubbard, Keisha B. Walters, and Dave C. Swalm, Mississippi State University, Mississippi State, MS 39762
Phospholipids with a glycerol backbone are known as glycerophospholipids or Phosphoglycerides. In all phosphoglycerides, there are two fatty acid chains and one Phosphorylated alcohol functionality on a glycerol backbone. Our goal is the selective Cleavage of the phosphate ester bond which will produce two materials, the di-fatty acid and the phosphate-containing molecule. The fatty acid portion can be used in the manufacture of biodiesel and other bio-fuels. We plan to use the phosphate molecule to functionalize polymeric surfaces for pH-responsive and bioaffinity applications. The Phosphate ester cleavage reaction conditions have been studied and the results are analyzed. The phosphoglycerides investigated include Phosphatidyl Choline Phosphatidyl ethanolamine and Phosphatidyl serine. The catalytic effect of lithium and Zinc hydroxide in the ester cleavage was also evaluated. Zinc or lithium halides, Potassium hydroxide was combined in chloroform to form the reaction solution. The selectivity and efficacy of the cleavage reaction was monitored as a function of reaction time and temperature using gel permeation chromatography (GPC), transmission and attenuated total reflectance (ATR)-FTIR spectroscopy, and x-ray photoelectron spectroscopy (XPS).
2:00 DEVELOPMENT OF RENEWABLE POLYMERS FROM 1,3-PROPANE DIOL AND MALONIC ACID
Mathew D. Rowe*, Erin M. Smith, and Keisha B. Walters, Mississippi State University, Mississippi State, MS 39762
The goal of this research is to develop biodegradable copolymers from biomass-derived starting materials. The monomers, 1,3-propane diol and malonic acid, were selected based on the presence of reactive functional groups and accessibility to materials. Catalyst function, synthesis conditions, and polymer characterization of the polycondenstation reactions will be presented. Catalyst, temperature, and monomer ratio were varied and the effect on copolymer yield and properties studied. The catalysts were selected based on the criteria of being environmentally benign and biocompatible and include zinc chloride, aluminum chloride, iron(III) chloride, and tin(II) chloride. Polymer synthesis was verified and the chemical composition characterized using Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). Differential scanning calorimetry (DSC) was used to determine the glass transition and melting temperatures of these polymers. The average molecular weight and molecular weight distribution was determined by gel permeation chromatography (GPC). By varying the monomer ratio, we have produced copolymers with varying chemical composition, molecular weights, and bulk properties. Using environmentally benign catalysts, the synthesis of renewable polymers from 1,3-propane diol and malonic acid has been successfully achieved. These renewable polymers will be evaluated for their potential use in commercial film and fiber production.
2:30 COMPARISON OF STORAGE STABILITY OF CATFISH BIODIESEL WITH AND WITHOUT ANTIOXIDANT
Supanee Danviriyakul (1), Saowalee Jongrattananon (2), and Juan Silva (2*), Chandrakasem Rajabhat University. Bangkok, Thailand and Mississippi State University, Mississippi State, MS 39762
The effect of an antioxidant on the properties of catfish biodiesel under accelerated storage conditions was studied. The samples with (800 ppm TBHQ) and without antioxidant (control) were stored at 80oC for 28 days. At specified time intervas, samples were taken out for analysis of peroxide value, anisidine value, TBARs, acid value, iodine value, UV absorbance, and induction time. The progress in the oxidation was slow at the beginning of the storage. Only small increases in peroxide value, anisidine value, acid value, and UV absorbance were observed from both control and TBHQ added samples. The changes were, however, more pronounced in the control sample. After 21 days, peroxide value, acid value, and UV absorbance started to rise very rapidly. The induction time was increased by the addition of TBHQ at 800 ppm. Changes during storage were not conclusive due to the variations in the measured value, especially at higher values. With the addition of an antioxidant, catfish biodiesel can withstand adverse conditions much better than the control, showing only slight changes in the measured values. Anisidine value, acid value, and UV absorbance were among the potentially oxidative index candidates that can be used to predict the quality of biodiesel related to its effect on engine performance.
2:45 SYNTHESIS, CHARACTERIZATION OF TRIS(2,2'-BIPYRIDYL) RUTHENIUM (II)-LOADED MICROCAPSULES AND THEIR BI0-RELATED APPLICATIONS BASED ON ELECTROGENERATED CHEMILUMINESCENT (ECL) DETECTION
Tommie Pittman*, Laura G. Kolibal, Marek W. Urban, and Wujian Miao, University of Southern Mississippi, Hattiesburg, MS 39406
An ultrasensitive DNA hybridization detection and a sandwich-type immunoassay methodology using polymerized liposome-based microcapsules loaded with water soluble ECL labels of tris(2,2\'-bipyridyl)ruthenium(II) (Ru(bpy)[.sub.3]2+) is reported. Ru(bpy)[.sub.3]2+-loaded liposomes with surface functional groups, such as -COOH or -N[H.sub.2], were prepared on the basis of our recently reported technique. The lipsomes were produced from phospholipid molecules such as phosphatidylserine (DOPS) and phosphatidylethanolamine (DOPE) after solubilization in chloroform and subsequent evaporation forming a lipid film. This film was rehydrated with a 20 mM Ru(bpy)[.sub.3][Cl.sub.2] aqueous solution along with low concentrations of styrene monomer and photoinitiator species before proceeding to gently agitation to form Ru(bpy)3Cl2 multilamellar vesicles. A micro-extruder with 3-5 [micro]m polycarbonate membranes was then used to produce monodisperse unilamellar vesicles while allowing the styrene monomer and photoinitiator species to penetrate through the outside lipid layer and remain in the hydrophobic zone of the liposome. Photo-polymerization process was carried out and Ru(bpy)[.sub.3]2+-loaded microcapsules with a layer of polystyrene were produced. The characterization of the liposomes was carried out with transmission electron, scanning electron, and optical microscopy etc. The detection of DNA and protein with above prepared microcapsules using ECL will be presented. Financial support through USM-MRSEC (NSF-DMR 0213883) program is gratefully acknowledged.
3:00 ADVANCES TOWARD BIOLOGICALLY ACTIVE CORE-SHELL FERROFLUIDS
Erin Fortenberry*, David Heaps, Steven Stevenson, and Paige Phillips, University of Southern Mississippi, Hattiesburg, MS 39406
Functional ferrofluids are prepared having core-shell structures with surface-active groups, which may serve as chemical agents such as catalysts. These magnetic particles allow for easy removal of the agent on command, by using a simple bar magnet extraction procedure. Composition of core-shell agents consists of a magnetite core material due to its low toxicity and well-characterized magnetic behavior and inorganic or polymer shell. Recent efforts to prepare biologically active core-shell magnetite particles are described. Dynamic light scattering techniques are used to monitor particle size in aqueous media, and zeta potential measurements are used to describe surface charge.
3:15 Divisional Awards Presentation
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|Publication:||Journal of the Mississippi Academy of Sciences|
|Date:||Jan 1, 2007|
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|Next Article:||Ecology and evolutionary biology.|