Question

A. How can you interface these two systems based on what you learned? Think about the limitations such as vacuum vs. pressure. 1. A gas chromatograph to a mass spectrometer 2. A liquid chromatograph to a mass spectrometer

Answer 1

Gas Chromatograph can be easily coupled to a mass spectrometer. It is called Gas-Chromatography Mass Spectrometry. gas chromatography can be used at normal temperature and pressurization is not needed. Mass spectrometry needs an inert atmosphere and vacuum to facilitate proper measurement. Sometimes two gases may be eluted at the same time from the chromatograph, but that is rectified by the mass spectrometer.

LCMS is fundamentally incompatible as the Liquid medium is pressurized liquid and MS unit is under Vacuum. For that, The moving bed interface was developed.This interface consists of an endless moving belt receiving the LC column effluent. On the belt, the solvent is evaporated by gently heating and efficiently exhausting the solvent vapour under reduced pressure in two vacuum chambers. After removing the liquid phase, the analytes desorb from the belt and migrate to the MS ion source to be analysed.