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DEVELOPMENT OF TECHNIQUES IN A LINKED GAS CHROMATOGRAPHY FOURIER TRANSFORM INFRARED FOURIER TRANSFORM MASS SPECTROMETER AUTOMATED MIXTURE ANALYSIS SYSTEM (DIRECT-LINKED, GC/IR/MS, GC/FT IR/FTMS)

GREGORY MARION BRISSEY, University of Nebraska - Lincoln

Abstract

The development of a linked gas chromatography Fourier transform infrared mass spectrometer (GC/FT-IR/MS) system has been reported previously; however, in this work the link GC/FT-IR/MS has been extended by developing of new techniques. Reported here is the development in part of an automated analysis of the multi-dimensional data obtained from such a system. The use of either FT-IR or mass spectrometry yields considerable information about a compound's identity; however, there exist many cases where the individual usage of either technique can lead to ambiguous compound identification. This is even more pronounced in a computer analysis scheme since the expertise of a human interpreter is extremely difficult to incorporate in computer algorithms. In the case of computer-readable library search in either FT-IR or mass spectrometry, picking the correct compound from a list is a hit and miss proposition. With the use of the linked techniques, complementary information correlations can be used to aid in unambiguous compound identification. Correlations of the reconstructed chromatograms from IR and MS led to a definitive study was made of a controversial Gram-Schmidt reconstruction method in FT-IR. The data analysis system was applied to 17 component mixtures. In addition, the time saving approach of taking both electron impact and chemical ionization data within the same GC/IR/MS run was tested. Several structural comparison techniques were investigated as to their ability to aid in the manual interpretation of compounds that were not identified by using the IR and MS search result comparisons. One of the major limiting factors in GC/IR/MS has been the low sensitivity of IR. A new technique, which increases the infrared spectrometer's dynamic range and improves the sensitivity problem, was tested.

Subject Area

Analytical chemistry

Recommended Citation

BRISSEY, GREGORY MARION, "DEVELOPMENT OF TECHNIQUES IN A LINKED GAS CHROMATOGRAPHY FOURIER TRANSFORM INFRARED FOURIER TRANSFORM MASS SPECTROMETER AUTOMATED MIXTURE ANALYSIS SYSTEM (DIRECT-LINKED, GC/IR/MS, GC/FT IR/FTMS)" (1984). ETD collection for University of Nebraska-Lincoln. AAI8427897.
https://digitalcommons.unl.edu/dissertations/AAI8427897

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