Direct interface of chemistry to microbiological systems: membrane inlet mass spectrometry.
Direct measurement of dissolved gases and low molecular weight volatiles through permeable membranes (e.g. 50-microm-thick silicone rubber), provides an invaluable tool for the investigation of the activities of microorganisms in the laboratory and in their natural environments. Multiple molecular species are monitored at a single point. Fast response times (t(90%)<1 min) and long-term stability, (<1% week(-1)); high specificity and high sensitivity (e.g. 0.2 microM for O(2), <0.5 mM for ethanol), provides a technique that can provide information on the kinetics of processes over many decades (10(0)-10(6)) of minutes. Spatial resolution of <1 mm enables 3D mapping of gases in complex ecosystems (sediments, peat, soils, biofilms, foodstuffs). Results with membrane inlet mass spectrometry (MIMS) when used in conjunction with confocal scanning laser microscopy, provides a powerful approach to the analysis of kinetic and spatial aspects of natural environments. Examples discussed are peat cores and cheese.
Lloyd
David
D
BIOSI 1 (Microbiology), Cardiff University, P.O. Box 915, Cardiff CF10 3TL, Wales, UK. floydd@cardiff.ac.uk
Thomas
Katie L
KL
Cowie
George
G
Tammam
Jonathan D
JD
Williams
Alan G
AG
D001419:Bacteria / Q000737:chemistry / Q000302:isolation & purification*; D002245:Carbon Dioxide / Q000032:analysis*; D002611:Cheese / Q000382:microbiology; D013058:Mass Spectrometry / Q000379:methods*; D008697:Methane / Q000032:analysis*; D012988:Soil Microbiology
D002245:Carbon Dioxide; D008697:Methane