ANALYSIS OF STYRENE OLIGOMERS BY PARTICLE BEAM LIQUID-CHROMATOGRAPHY MASS-SPECTROMETRY

We have investigated the transport properties of a particle beam liquid chromatograph/mass spectrometer interface using oligomers of polystyrene as test molecules. The polystyrene system was chosen because it is available in a well-defined series of oligomers spanning the mass range of our spectrometer and because polystyrene is known to undergo thermal degradation in a conventional solids insertion probe inlet. The results indicate that intact styrene oligomers with molecular weights up to approximately 2000 were quantitatively transferred through the interface and into the mass spectrometer ion source. Using electron impact ionization, we observed molecular ions out to the n = 18 oligomer at mass 1930, well beyond the highest reported molecular ion detected by using solids insertion probe sample introduction systems.