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Eight compounds from a Kentucky 1R4F reference cigarette smoke condensate have been determined by selected ion monitoring-mass spectrometry (SIM-MS) to confirm the validity of multidimensional gas chromatography (MDGC) as a quantitative tool in complex mixture analyses. Four electrostatically precipitated smoke condensate samples of 100 cigarettes each are dissolved individually in 25 mL of 2-propanol. The 2-propanol contains two methyl esters (C8 and C14) and seven deuterium-labeled compounds used as internal standards (IS). Analysis of the compounds of interest, pyridine; acetamide; acrylamide; phenol; o-, m-, and p-cresol; and quinoline, is accomplished by using two heartcuts. Heartcut times of the MDGC analysis are selected such that at least one IS is transferred with each group of compounds being analyzed. This study shows that the MDGC technique previously developed and described can be used for quantitative analyses. A comparison is made between the two types of internal standards. The results obtained for both types of internal standards agree within 20% of each other, on the average, with higher standard deviations for approximately 60% of the compounds where methyl esters are used as internal standards.

Matrix-isolated (MI) Fourier transform infrared spectra (FT-IR) have been collected on a series of aldehydes and acids. The values for the carbonyl absorption are intermediate between the higher values for vapor-phase (VP) and lower values for solid-state (SS) phases. Substituent effects on aromatic rings induce shifts in carbonyl absorptions in the same manner as found in VP and SS studies. The magnitude of the shifts is approximately the same for all three phases. The spectra reveal a splitting or broadening of the carbonyl absorption for both aldehydes and acids. The size of the molecule affects the degree of band broadening. In certain cases discrete conformers appear to have been isolated in the matrix.

Matrix-isolated (MI) Fourier transform infrared spectra have been collected on a series of aliphatic ketones. The values for the carbonyl absorptions maxima are intermediate between vapor-phase (VP) and solid-state solution (SS) phases. The data reveal a stereochemical influence on the position of the ketone carbonyl absorption when the carbons that are in the alpha position with respect to the carbonyl group contain alkyl snbstituents vs. protons. Steric bulk causes the frequency of the absorption to decrease. The position of the ketone carbonyl absorption was also shown to decrease as the carbonyl group migrated toward the center of a long straight-chain hydrocarbon backbone. Stereochemical influences due to ring strain were also documented. Unsaturation, located in the alpha position with respect to the carbonyl, was shown to reduce the absorption frequency. The trends found in this MI study are comparable to those previously documented from VP and SS studies. In two cases wherein very bulky substituents were located in the alpha position with respect to the carbonyl, a splitting of the carbonyl absorption was observed. Studies are underway to test for a general trend in and to uncover an explanation for this phenomenon.