Printer Friendly

Effect of Oleic Acid on the Permeation Kinetics of Diclofenac Diethylamine.

Byline: SYED NISAR HUSSAIN SHAH, MUHAMMAD SALMAN, MASHOOD AHMAD,MAHBOOB RABBANI AND AMIR BADSHAH

Introduction

Summary: In vitro permeation studies were done using modified Franz diffusion cell through rabbit skin and silicone membrane utilizing different ratios of oleic acid with diclofenac diethylamine (DDA) in normal saline and methanol mixture during present study. Solubility studies indicated linear increase in drug solubility with carrier concentration. The enhancing effect of all the enhancer's ratios was found to be significantly greater than that of standard without enhancer (control). 'Benchmark' values with which to compare the performance of the vehicle are the flux values which were statistically no significant difference (P greater than 0.05) across rabbit skin and silicone membrane. The input-rate values of all the ratios have shown a constant trend. The vehicles used were predominantly influencing the partition of the drug into the skin rather than the diffusion throughout the study.

Consequently, changes in diffusion and/or partition may occur as a result of absorption or depletion of permeation enhancer inside the membrane/or skin over time which validates our results.

The Drug-vehicle based enhancement approach is exploited to circumvent the stratum corneum and to increase the flux through skin membrane, is used in transdermal research as better alternative method to enhance permeation of drugs through skin [1]. The use of oleic acid (OA) like other saturated (stearic acid) and unsaturated (linoleic acid etc.) fatty acids for drug permeation enhancement is of interest in the area of topical and percutaneous absorption research and has shown to be effective penetration enhancer for many drugs in earlier studies [2, 3].

As penetration enhancer, oleic acid which increases skin permeability appears to act selectively on the extracellular lipids representing the main regulatory channel for the penetration of small membrane-vehicle partitioning tendency of the drug [6, 7].The aim of this study was to investigate the effect of oleic acid as penetration enhancer when used in different concentrations in the solution, on the percutaneous absorption of DDA in vitro.

Results and Discussion

Pre-formulation studies and pH determination was shown in Table-1 and 2, respectively. All other physical parameters like viscosity and homogeneity were also given in Table- 2.

Table-1: Preformulation study of drug

###Solubility (mg/mL)###Partition co-###pKa###M.Po

###Wate NS###OA###efficient Ko/w###C

###r

DDA + 1ml###42.28###199.2###4.40###4.07###280

methanol

+ 1ml###+-0.59###3###3

Nitric

acid will###+-1.39###21.2

produce###

red color###7

Table-2:Values for evaluation of Physicaj parameters

Vehicle(OA) pit###%Drug###Viscosity###Rabbit Skin ftomogeneit

Percentage###Content (dyn.s/cm2)###extraction y

###(mg/mL)

###6.2+-0.1###98.56###0.91x10-4###1.32###Good

###2###6.2+-0.1###98.74###0.83x10-4###1.17###Good

###3###6.2+-0.1###99.13###0.82x10-4###1.05###Good

###4###4.2+-0.1###98.87###0.82x10-4###1.03###Good

penetration enhancement and effect of surfactants is primarily believed to be due to the promotion of

The solubility of DDA in distilled water was 42.282+-0.588 mg/mL, at 32degC, which is in line with

To whom all correspondence should be addressed. values reported in the literature [7]. DDA was ~10 fold more soluble in oleic acid (413.33+-21.27 mg/mL) than water. In the present study, co-solvent mixtures of DDA were made from saturated solutions of enhancer in water as OA:water mixture at 20:80; 40:60; 60:40; 80:20 and100:00 ratio (v/v) respectively as given in Table-3 and then degree of saturation (DS) was calculated (i.e. 1.2).

Solubility Enhancement Ratio ( ERsol) of DDA in both solvents have been determined as: ERsol= Ct /Cs

where Ct is concentration of DDA in presence of enhancer and Cs is concentration of DDA in absence of enhancer (control) and observed ERsol was 9.77561 for OA. This trend was previously described using the same co-solvent mixture [8].

FTIR Spectra

Table-3: Solubility of Diclofenacdiethylamine in Oleic Acid/water vehicles.

% Oleic Acid in water (v/v)###Solubility (mg/mL)+-SD(n=3)

0###42.28+-0.59

20###197.31+-12.61

40###274.23+-8.38

60###328.08+-1.92

80###376.80+-4.00

100###413.33+-21.27

Solvent Uptakeand Skin Extraction Measurements

The uptake was observed for normal saline which confirms the idea introduced above as the lipophilic solvents have solubility parameters closest to that of the membrane. The solubility parameter of silicone membrane is reported in the literature to be 7.5 (cal/cm3)1/2 by Cross et al. [10]. The DDA concentration determination within rabbit skin permeation parameters of the solutions, these values almost behaving as increase with the increase in the concentration of enhancer solution from 1% to 4%.Fig. 4 explains the enhancing ratio ER (J) and ER (D) and the values were observed in the order as 1% less than 2% less than 3% less than 4% which is comparable with the earlier work [13]. The input rate obtained is given in Table 5 which is almost 2-4 folds higher than for control.

The minimum standard deviation values assured that the process used for preparing the solution system is capable of giving reproducible results which is further confirmed by earlier studies data [14].

The effect of oleic acid in amount of 1%, 2%, 3% and 4% (v/v) in the Diclofenac [11, 12] solutions on the permeability rate through rabbit skin was shown in Table-4 and Fig. 2 which explained all the permeation parameters with associated standard deviations(+- SD). The OA might affect fluidity of SC

Table-4: Permeation kinetics of Diclofenac-Diethylamine in the presence of oleic acid through Rabbit Skin (n=5) at 37degC+2. structure and DDA could be permeated better through the rabbit skin. This famous penetration enhancer 'OA' penetrated into the SC, decompressing it and reduced it's resistance to drug penetration [3] which explained our results. Fig. 3 explained the enhancing ratio ER (J) and ER (D) and ER (J) was observed in the order as 1% less than 2% less than 3% less than 4% while same trend was also observed in ER (D) which is comparable with the earlier work. The input rate obtained is given in Table-5 which is almost 9-12 folds higher than for control.

II-Kinetics of Permeation Studies through Silicone Membrane

The permeation of Diclofenac solutions through silicone membrane, using OA of varying concentrations (1%, 2%, 3% and 4% v/v) was evaluated and enlisted in Table-6. There is no significant difference (P greater than 0.05) between all

Flux D K K

###Flux###D###K###K###

Vehicle (ug/cm2/min) (cm2.miW1)###cm.min-1###x10-4###ER

(OA)###+-SDx103###x 10.2###x10-4###+-SDx10-9

% age###+- SDx10-4###+- Sub

###1###14.24

###0.7725###9.34###0.58###2.00

###+- 1233

###+- 2.306###+-27.89###+-49.78

###11.28

###0.862###10.43###0.82###2.23

###2###+- 39.91

###+- 10.472###+-126.7###+-382.0

###3

###1.035###5.65###12.52###1.96###2.68

###+- 28.74###+- 52.14###+-3.47###+-0.225

###4###1.095###6.00###13.25###1.95###2.83

###+- 39.43###+- 23.65###+-4.77###+-8.26

###0.105###118.13###0.053###0.039

Control###+- 0.0005###+-23.41###+-0.27###+-0.009

Table-5: Input-rate of DDA in different concen- trations of vehicle's solutions across rabbit skin and silicone membrane (n=5) at 37oC+-2.

Vehicle (OA)###Rabbit Skin###Silicone Membrane

%age###(ug/min)###(ug/min)

1###0.121###0.631

2###0.135###0.655

3###0.163###0.713

4###0.172###0.764

Control###0.061###0.031

Discussion

It is not explicit for sometime increasing the lipid solubility, the partition coefficient (K) between a lipid and water, has been the standard working paradigm for increasing permeation of the skin and the permeability coefficient (kp = distance/time) has been the quantitative measure of the results. The shorter chain and more water soluble alcohols exhibiting lower (K) values gave the greater flux values (J = amount/areaxtime; the more clinically relevant measure of permeation) and D values, regardless of whether they were applied neat or in an aqueous vehicle as in this study while Kp showed opposite trends for the solutions [15].

The permeation rates of the drug calculated from the permeation profiles of each ratios are shown and among these tested, the ratio which was composed of 2% DDA, 4% (v/v) of Oleic acid showed the highest permeation rate

1.095+-39.43ug/cm2/min). The quantity of OA in solution affected the skin permeation rate of DDA significantly (Fig. 2). As the amount of OA was decreased from 4% (v/v) to 1% (v/v) the skin permeation rate of DDA also decreased which may be due to thermodynamic activity of drug in the solution as DDA is poorly water soluble (42.282+- 0.588 mg/mL) and yet in the enhancers' mixture [4].

The reported data in this study (Fig. 4, 5) showed that K is increasing and D is decreasing from 1% (v/v) to K is increasing and D is decreasing from 1% (v/v) to 4% (v/v), hence permeation through rabbit skin is partitioning; although diffusion is occurring in the skin as the earlier studies confirmed the deposition of DDA into the skin [16].

It was also found that the permeation of the DDA in solution was significantly influenced by the presence of ethanol. The literature supported our data that skin permeation rate of DDA was increased by 7- 9 folds [17]. It is possible that in the presence of SYED NISAR HUSSAIN SHAH et al., J.Chem.Soc.Pak., Vol. 34, No. 1, 2012 5 alcohol, the size of internal phase of the solution may be decreased, making the surface area of the droplet increased significantly and the influence of alcohol in solutions upon the transport behavior of several ermeants across the skin has been evaluated earlier [18, 19]. It has been reported that alcohol may alter or form additional pore/polar pathways in the stratum corneum as a result of combination of changes in protein conformation, reorganization within the lipid polar head region or lipid extraction and also induced the reduction in the barrier property of SC [20].

As the %age (v/v) of oleic acid was increased, the number of internal phase (aqueous and lipid channels) was increased which increased the permeation rate of drug [4] as in 4% solution flux value was 1.095+-39.43 (ug/cm 2 /min) and 0.973+-12.17 (ug/cm 2 /min) in rabbit skin and silicone membrane respectively whereas in 1% solution it was 0.7725+-2.306 (ug/cm 2 /min) and 0.803+-12.67 (ug/cm 2 /min) respectively (Fig. 2, 3). Solution ratios used in this study enter the SC, change its solution properties by altering the chemical environment and thus dissolve the barrier capacity of the cutaneous layer [21]. Input Rate of the solutions of was 0.1613ug/min. The lyophilic domain of the solution can interact with the stratum corneum.

DDA dissolved in the lipid domain of the solution can directly partition into the lipids of the stratum corneu or the lipid vesicle themselves can intercalate between the lipid chains of the stratum corneum, thereby destabilizing its bilayer structure. In effect, these interactions will lead to increase the permeability of the lipid pathway to DDA. Consequently, the OA influences the penetration in accordance with earlier studies [22, 23]. The lag time always played a significant role in the percutaneous absorption of the drug and was calculated from x- intercept of the slope at the steady state.

As OA partition into and interact with SC constituents to make a temporary, reversible increase in skin permeability and after passing definite time, the equilibrium will be created; it is more important that the lag time must be in an agreeable range if topical solutio s possess lag time because they have less resident time on skin [24].

In summary, we utilized Drug-vehicle based enhancement approach to evaluate the enhancing effect of OA through silicone membrane/or rabbit skin, however, the earlier scientists [25] presented results to demonstrate that topical application of OA induces stratum corneum lipid structure disorder in vivo. OA may enhance percutaneous penetration mainly through a dual mechanism involving stratum corneum lipid bilayer perturbation and lacunae formation as earlier studied by Jiang [26]. The results revealed that lipophilic enhancers were more effective than lipophobic ones [27] and in simple diffusion experiments, this is very difficult to reveal possible interactions and it could be irrational to try and do so.

Comparison of Saturated Solution Across Rabbit Skin vs Silicone Membrane In this study, FoD value obtained was 1.51 (Table-7), showing that the flux values determined by using silicone membrane (SM) were in the same order of magnitude as that of flux values calculated with rabbit skin as illustrated in Fig. 6-8 for permeation study after 3 hours. Thus, considering all this discussion together with the FoD (Table-7), this animal model (Rabbit skin) and silicone model membrane can be regarded as predictive of human skin permeability [28].

Table-7: The factor of difference value (FoD) in the presence of saturated enhancer's solution across rabbit skin and silicone membrane (n=5) at 37oC+-2. determined by cutting Silicone membrane and rabbit skin to an appropriate size (~1cm2) and weighed. They were then placed in a sample bottle containing the vehicle and soaked for 24 hours. The membranes were blotted dry with tissue paper and re-weighed. The experiments were performed in triplicate, at room temperature. The amount of solvent taken up by the membrane was expressed as a weight percent. The solvent uptake is expressed in the following equation as:

The experiments were performed at 37oC+-2 in triplicate.

The Factor of Difference Value (FoD)

The flux (J) values calculated from the present permeation study of saturated formulations of DDA has been compared (rabbit skin permeability data vs silicone membrane data) by means of the factor of difference value (FoD) described by the following Dick and Scott equation;where JRS and JSM denotes maximum flux value (J) through rabbit skin (RS) and silicone membrane (SM). This study suggested that the artificial membrane model represents a significant prediction for the human skin behaviour if its associated FoD value is less than 3 [31].

Diffusion Studies through Rabbit Skin and Silicone Membrane

Diffusion studies across rabbit skin and silicone membrane were performed using Franz-type diffusion cells (made of Germany at SOP, London) that have a receptor phase of ~4.5 mL and a diffusion area of ~0.85cm2. The full thickness rabbit skin was taken from the abdominal surface and hairs were carefully cut as short as possible using scissors, without damaging or scratching the skin surface. Rabbit Skin/or sheets of silicone membrane were cut according to the diameter of the diffusion cell. The skin was placed in a normal saline solution before mounting on to the diffusion cell [32]. Both rabbit skin and silicone membrane were soaked overnight in the receptor solution i.e. NS. The skin/ or membrane was then placed between the two compartments of the diffusion cells using Silicone grease (Dow, USA) to produce a leak-proof seal between the membrane and the two compartments of the diffusion cell.

The receptor compartment was filled with NS and each solution (1 mL) was placed in the donor compartment. To remove air bubbles and prevent the buildup of air pockets in the receptor phase, NS was degassed in an ultrasonic bath. To prevent evaporation from the receptor compartment, the cell arm was covered with a glass lid. Uniform mixing of the receptor solution was obtained with a magnetic stirrer that was placed in the receptor compartment. The diffusion cells were placed on a stirring bed immersed in a water bath at 35degC+-2. After one hour interval, the receptor solution was completely removed and refilled with fresh pre-thermostated NS. Sink conditions were met in all cases. From the side arm of the receptor compartment, 0.5 mL of the sample was drawn each time at an interval with the help of 1 mL syringe (Sun, Korea) and correcting the receptor half cell volume with pre-thermostated NS.

The sample taken from the receptor cell was run on U.V. spectrophotometer (Agilent2005; software version 2005) at the wavelength of 276 nm. The diffusion experiments were performed under occluded conditions by covering the donor compartment with Para film. All experiments were performed at 37degC+-2 in +-SD (n=5) and sampling time was 0-3 hours with predetermined intervals for silicone membrane while 24 hours for rabbit skin studies.

Statistical Analysis

Data analysis was carried out using Microsoft Excel version 2007. Statistical significance was determined between the sample means of the treatment groups using the one-way ANOVA. A probability of p less than 0.05 was considered statistically significant. All results are presented as the mean +- SD, unless otherwise stated.

Conclusion

we could conclude that the enhanced permeation of DDA may be by the partitioning of the drug into the stratum corneum and also by modifying intercellular lipids, disrupting their highly ordered structure and thus increasing the diffusion of DDA through the membrane with increased solubility and it is important to observe the increased amounts of DDA in the skin may also be retention of the drug by the skin. The benefit of penetration enhancement in this study was counterbalanced by the fact that at this range of concentration, the use of OA cannot harm the skin.

Declaration of Interest

The authors report no conflicts of interest.

Acknowledgement

The authors are greatly thankful to Bahauddin Zakariya University, Multan for financial support and HEC for award of training scholarship (IRSIP) for PhD scholars which helped the corresponding author to facilitate the work at London School of Pharmacy.

References

1.L.D. Dinesh, A.R. Amit, S. Maria, R. Swaroop, Lahoti, H. G. D. Mohammad, International Journal of Pharmacy and Pharmaceutical Sciences, 1, (1), (2009).

2. S. B. Kuljit and S. Jagdish, Journal of Pharmaceutical Science, 87, 462 (1997).

3. B. J. Aungst, J. A. Blake and M. A. Hussain, Pharmaceutical Research, 7, 712 (1990).

4. K. S. Faaberg, G. A. Palmer, C. Even, G. W. Anderson, P. G. W. Plagemann, A. Naik, L. A. R. M. Pechtold, R. O. Potts and R. H. Guy, Journal of Controlled Release, 37, 299 (1995).

5. S. A. Mortazavi, R. Aboofazeli, International Journal of Production Research, 2, 135 (2003).

6. J. H. Kweon, S. C. Chi and E. S. Park, Arch. Pharm. Res., 27, 351 (2004).

7. B. Mukherjee, Kanupriya, S. Mahapatra, S. Das and B. Patra, The Journal of Applied Research, 5, 1, (2005).

8. S. Mohammadi-samani, A. Jamshidzadeh, H. Montaseri, M. Rangbar-zahedani and R. Kianrad, Pakistan Journal of Pharmaceutical Sciences, 23, 83 (2010).

9. S. N. H.Shah, S.Asghar, M. A.Choudhry, M. S. H. Akash, N. Rehman and S. Baksh, Drug Development and Industrial Pharmacy, 35, 1470 (2009).

10. S. E.Cross, B. M. Magnusson, G. Winckle, Y. Anissimov, M. S. Roberts, Journal of Investigatice Dermatology, 120, 759 (2003).

11. A. Madni, M. Ahmad, M. Usman, M. M. Zubair, M. Qamar-uz-Zaman, H. M. Shoaib, A. Munir, S. A. Khan, M. N. Amir and M. S. Qureshi, Journal of the Chemical Society of Pakistan, 32, 654 (2010)

12. Fazal-ur-Rehman, M. F. Khan, I. U. K. Marwat, G. M. Khan and H. Khan, Journal of the Chemical Society of Pakistan, 32, 462 (2010).

13. J. Borras-Blasco, O. D'iez-Sales, A. Lopez and M. Herraez-Dom'inguez, International Journal of Pharmaceutics, 269, 121 (2004).

14. S. Jayaprakash, S. Mohamed Halith, P. U.Mohamed Firthouse and Yasmin, M. Nagarajan, Pakistan Journal of Pharmaceutical Science, 23, 279 (2010).

15. K. B. Sloan, S. C. Wasdo and J. Rautio, Pharmaceutical Research, (12), 2729 (2006).

16. P. G. Green, R. H. Guy and J. Hadgraft, International Journal of Pharmaceutics, 48, 103 (1988). 17. M. Walker and J .Hadgraft, International Journal of Pharmaceutics, 71, R1 (1991).

18. Y. Obata, K.Takayama, Y. Machida and T. Nagai, Drug Design and Discovery, 8, 137 (1991).

19. K. Takayama and T. Nagai, 74, 115 (1991).

20. D. Bommannan, R. O. Potts and R. H. Guy, Journal of Investigative Dermatology, 95, 403 (1990).

21. B. W. Barry, European Journal of Pharmaceutical Science, 14, 101 (2001).

22. H. O. Ho, L. C. Chen, H. M. Lin and M. T. Sheu, Journal of Controlled Release, 51, 301 (1998).

23. Y. Ota, A. Hamada, M. Nakano and H. Saito, Drug Metabolism and Pharmacokinetics, 18,261 (2003).

24. Y. Javadzadeh, J. Shokri, S. Hallaj-Nezhadi, Hamed Hamishehkar and A. Nokhodchi, Pharmaceutical Development and Technology, 15, 619 (2010).

25. M. L. Francoeur, G. M.Golden and R. O. Potts, Pharmaceutical Research, 7, 621 (1990).

26. S. J. Jiang and X. J. Zhou, Biological and Pharmaceutical Bulletin, 26, 66 (2003).

27. M. Yamada, Y. Uda, Y. Tanigawara, Chemical and Pharmaceutical Bulletin, 35, 3399 (1987).

28. F. Cilurzo, P. Minghetti and C. Sinico, AAPS PharmSciTech., 8, 94 (2007).

29. S. D. Roy, M.Gutierrez, G. L. Flynn and G. W. Cleary, Journal of Pharmaceutical Science, 85, 491 (1996).

30. S. H. Yalkowsky, T. J. Roseman (eds): Techniques of Solubilization of drugs. New York: Marcel Dekker, Inc. 91-134(1981).

31. I. P. Dick and R. C. Scott, Journal of Pharmacy and Pharmacology, 44, 640 (1992).

32. Shah SNH, Rabbani ME and Amir MF, "In vitro study of percutaneous absorption of diclofenac in the presence of SLS through hairless rabbit skin," J of Res. (Sci.), 16, 1, 45-50 (2005).

33. R. H. Guy and J. Hadgraft, Marcel Dekker, New York (2003).
COPYRIGHT 2012 Asianet-Pakistan
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2012 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Shah, Syed Nisar Hussain; Salman, Muhammad; Ahmad, Mashood; Rabbani, Mahboob; Badshah, Amir
Publication:Journal of the Chemical Society of Pakistan
Article Type:Report
Geographic Code:9PAKI
Date:Feb 29, 2012
Words:3606
Previous Article:Effect of Different Locations, Varieties and Micronaire Values upon the Non-Cellulosic and Metal Contents of Cotton.
Next Article:Development of Sensor Calibration against Standards using Measurement Software TestPointTM-CEC and Application to the Verification of pH Electrodes.
Topics:

Terms of use | Privacy policy | Copyright © 2021 Farlex, Inc. | Feedback | For webmasters |