On-line monitoring of dissolved gases using microporous membrane inlet andmass spectrometry

Mass spectrometry has been widely used for the monitoring of fermentation p rocesses, since it allows the on-line analysis of gas streams and of dissol ved gases or volatile components in fermentation broths. In the present stu dy, an interface modul consisting of a microporous hydrophobic hollow fibre membrane was proposed. This module, installed in an external loop, worked as a gas contactor between a stream of recirculating liquid and a carrier g as which was analysed by the mass spectrometer. The feasability of such sys tem was demonstrated and optimisation procedures in order to achieve satisf actory analysis sensitivity and response times were discussed.