ABSTRACT
Numerous ambient direct ionization methods have been introduced for use with mass spectrometry over the last several years.(1-20) A major advantage of these methods is speed of analysis, which is achieved not only by the fast insertion and ionization of the sample, but by the elimination of most sample preparation and chromatographic separations. However, this presents a problem in materials analysis and for mixtures in general because of the complexity of the mass spectra that result from direct analysis of complex mixtures. The atmospheric solids analysis probe (ASAP)(2,21) mass spectrometry (MS) method offers some separation related to volatility by control of the heated gas used to effect vaporization, but this is not sufficient for many mixtures. Ion mobility spectrometry (IMS) offers rapid gas-phase separation of ions based on differences in charge state and collision cross section (CCS) (size/shape). Here we explore the utility of a commercial IMS/MS instrument with ASAP sample introduction for analysis of complex mixtures.
