Ptr-ms Technology for Process Monitoring and Control in Biotechnology

Process monitoring is becoming increasingly relevant in biotechnology, especially in the manufacturing sector to promote cost-effective production. Proton transfer reaction mass spectrometry (PTR-MS) is a well established analytical tool for the measurement of volatile organic compounds (VOCs) and offers fast, real-time detection and quantification of VOCs at trace concentrations. In addition, this technique requires no preconcentration or complex sample-handling prior to measurements. In a bioreactor, VOCs are emitted as by-products of microbial growth and development which may be used to gauge the activity of these micro-organisms. With realtime monitoring via the PTR-MS technique of the emitted VOCs in the bioreactor headspace, it may be possible to gain information for the control of the fermentation process. We have successfully developed a suitable sampling system that allows the PTR-MS measurement device to be coupled to a bioreactor in order to monitor fermentor off-gas in real-time. Using PTR-MS a large number of VOCs have been found which showed distinct variations over the course of a single fermentation bearing potential information for fermentation process control. Some of these marker masses have already been chemically identified and related to specific activity within the fermentation process.