On-line glucose measurements possible for fermentations.

Glucose is by far the most important source of nutrients in biotechnological and fermentation processes. This carbon source is used in almost 95% of all cultures. The preparation of increasingly more complex products by genetically engineered microorganisms requires you to comprehensively monitor various parameters. Quality assurance requires not only the analysis of such physical parameters as temperature and pH, but also the control of chemical variables, such as glucose.

Determining glucose concentrations is routinely important in fermentation processes. But many lab instruments are suitable only for making off-line measurements. An instrument that can make on-line glucose measurements will be significant. Toward this end, researchers at Trace Biotech AG (Mascheroder Weg 1b, D-38124 Braunschweig, Germany) developed the on-line Glucotrace system.

Glucotrace can be used primarily to monitor on-line any industrial process or culture that utilizes glucose as a carbon source, including batch, fed-batch and continuous-culture systems. Analyzing glucose in culture media requires that a sample be drawn under sterile conditions from a bioreactor. Glucotrace uses the flow diffusion analysis method, which employs time-dependent sample enrichment.

Through a sterilized immersible probe, a sample from a bioreactor diffuses across a membrane into a chamber in the system. The sample flows to a detector. An enzymatic reaction of the glucose generates a signal. The intensity of the signal indicates the concentration of the sample.

Further information. Andrea Ennenga; phone: [phone]; fax: [phone]; URL: http://www.trace-ag.de.