This Small Business Innovation Research (SBIR) Phase 1 project is in the general area of instrumentation development in the subfield of mass spectrometry. The combination of gas chromatography with mass spectrometry (GC/MS) provides the best general purpose analytical instrument for sensitive characterization of complex mixtures. It is used in fields of science and technology. In most cases, the gas chromatograph separates the starting mixture into its constituent compounds prior to analysis by the mass spectrometer. The separation step is the most time-consuming part of the analysis, often taking an hour, while mass analysis for each constituent is complete in a second or less. This project provides a method for the direct mass spectroscopic analysis of mixtures and can speed overall analysis time by reducing the degree of chromatographic separation. The investigators use a novel ionization modulation scheme that increases the amount of chemically useful information obtained from a mass spectrometer. The system is automated and supports computerized deconvolution of the resultant two-dimensional spectra. The Phase I program addresses optimization of the instrument design by maximizing the data acquisition rate (while maintaining good signal-to-noise ratios over a large dynamic range), determining the limits to sensitivity, determining the optimum electron energy resolution and selecting the best algorithm for computerized data reduction.
