GC/MS and the chromatographic challenge

Abstract

Application of high pressure drop (narrow-bore, vacuum-outlet) columns shortens analysis times and lowers detection limits at least in proportion to the reduced column diameter. In the scanning mode in GC/MS, only quadrupole instruments can meet this challenge for columns (with 105 plates I with diameters down to 30-50 mum. For still faster separations on even smaller bore columns only simultaneous ion collecting mass spectrometers are suited (e.g. time-of-flight instruments, magnetic mass spectrometers with "electronic" photoplates). The hitherto experienced bottleneck, the transport of vast amounts of mass spectral data per time unit to mass storage devices, can nowadays be overcome by storing all data in ever cheaper and ever expanding computer memory. Theoretically, there is no limit in gas chromatographic separation speed. One might speculate on GC/MS on the MS/MS time scale of mus. Current research indicates, however, that 10 mum i.d. columns are the limit in practice