On-line-Bestimmung von Enzymen in der Bioprozeßanalytik unter Berücksichtigung von Probenahme und Fließinjektionstechnik

Summary

The on-line determination of enzymes in biotechnical processes becomes an important factor with regard to process development and optimization. At present, most commonly enzymes are determined off-line in the laboratory after withdrawal of a separate sample. Wet chemical methods dominate in this respect, mainly because enzymes have to be measured according to the reaction schemes which are catalyzed by them. For an efficient process monitoring and control the time delay, the limited reliability and the man power needed for analysis of a large number of samples are crucial points. By using the technique of flow injection analysis (FIA) it should in general become easy to develop automatically operated enzyme determination procedures based on reaction schemes which can be used for fast and efficient process monitoring, providing the problems with the coupling of the analyzer at the bioreactor are solved. Continuous sampling in this respect plays a key role in developing on-line measuring techniques. This paper reviews the current status of on-line enzyme analysis, using flow-injection techniques. It is shown that the coupling problems can be solved by using a newly developed sampling module, which is based on membrane filtration. Some examples of on-line enzyme determinations in fermentation as well as in downstream processing illustrate the ease and reliability of the proposed concept for using FIA in connection with membrane separation.