Sampling, sample treatment, assay and real time monitoring of biotechnological processes using an integrated flow-injection system

Abstract: Microorganisms can be used for production of pharmaceutical substances. With the introduction of gene technology, it is possible to transfer information from one organism to the other, thereby making the receiving organism capable of producing substances that it did not so before. This development is very important for e.g. production of therapeutic proteins However, when using living organisms for production there is a need for controlling a range of different parameters. In order to understand the process it is necessary to have as much information as possible and then an algorithm to analyze the data. In this thesis work is presented that addresses some of the bottlenecks in development of process monitoring. The coaxial catheter was evaluated with regard to sampling from complex, sensitive medium without leakage of the inhibitory solution that is used for instantaneous stopping of ongoing enzymatic/microbial processes in the sample. An automated system for advanced flow injection analysis of complex biotechnological processes has been constructed and it was used to evaluate efficiency of different inducer combinations when expressing a clone of enzyme. One key factor in flow injection analysis is to prevent flow problems. The introduction of supermacroporous hydrogels made it possible to introduce whole broth from a fermenter into the system and also to include a superporous catalytically active gel composed of microbial cells directly cross-linked to each other. Even if there is a need, still very few successful examples are presented where advanced monitoring is used to control the processes. The missing part here is the lack of a reliable, representative and robust sampling and sample handling system, which is compatible with analytical devices. The objective of this thesis work was to develop an aseptic and representative sampling unit and treatment of the bioreactor product in the flow system, and finally, analysing the sample by enzymatic and immunoassays in the integrated flow system.