The rates of interactions of polycyclic aromatic hydrocarbons (PAHs) with biological cells studied with fluorescence appear to be different for cells from different origins. The monomer emission of benzo[<i>a</i>]pyrene (BaP) is enhanced as in liposomes, but more significantly in normal liver cells than in liver cancer cells or kidney cells, and that enhancement is proportional to the amount of cells added. When PAHs are allowed to interact with cells for a certain period of time, metabolism appears to occur. The excimer emission is seen to dissipate continuously as reactions proceed, whereas the monomer emission increases, passes through a maximum, then starts to decrease when excimer emission becomes exhausted. The time plot of the BaP excimer emission in semilogarithmic coordinates indicates that the decrease or the mass transfer of microcrystalline BaP to the cell membrane is a first-order process. Metabolism has been investigated by monitoring the monomer emission. Liver cells have higher monomer emission than the kidney cells in the early stages of interaction, indicating that these cell membranes are more amenable to PAH absorption. Effects of vitamin K<sub>3</sub> and radiation have also been investigated.
Ping Chiang, Kuang-Pang Li, and Tong-Ming Hseu, "Spectrochemical Behavior of Carcinogenic Polynuclear Aromatic Hydrocarbons in Biological Systems. Part I: Steady-State Fluorometry of BaP and BeP in Living Cells," Appl. Spectrosc. 50, 1345-1351 (1996)