An experiment suitable for college junior or senior students in the analytical instrumental analysis laboratory that demonstrates the analysis of PAHs (benzo[ a ]anthracene, benzo[ k ]fluoranthene, benzo[ a ]pyrene, chrysene, and phenanthrene) using absorption and fluorescence spectroscopy is described. This experiment is carried out during one seven-hour instrumental analysis laboratory. It could also be used in a physical chemistry laboratory to demonstrate fundamental spectroscopic and photochemical principles. A Beer–Lambert plot for an absorption peak of each PAH was obtained and used to determine the molar absorptivities. The effect of heavy atoms as quenchers of fluorescence was studied by using 1-bromoheptane and 1,7-dibromoheptane, and Stern–Volmer plots were prepared to determine the ratios of the quenching rate constants to the fluorescence rate constant, k Q / k f . The experiment is also useful as an experiment preceding the determination of PAHs by HPLC with absorption and fluorescence detection as described earlier ( J. Chem. Educ. 1998, 75, 1599 ).
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Rivera-Figueroa et al. (2004) studied this question.