ONLINE MONITORING OF BIOLOGICAL REACTIONS AT LOW PARTS-PER-TRILLION LEVELS BY MEMBRANE INLET MASS-SPECTROMETRY

A now-through membrane inlet combined with a single quadrupole mass sp ectrometer has been used for the direct on-line monitoring of biologic al reactions at the extremely low parts-per-trillion level. Linear sig nals over at least 4 orders of magnitude were obtained. As an example, on-line monitoring data from the microbial oxygenation of chloroethyl enes in pure cultures of the methanotrophic bacteria Methylococcus cap sulatus (Bath) are presented.