Liposomal uptake of microcrystalline benzo(a)pyrene studied with synchronous fluorescence

Synchronous fluorescence spectrometry is employed for kinetic studies of benzo(a)pyrene uptake by phospholipid bilayers. It provides several advantages over the conventional mode. These include less background interferences, higher sensitivity, and relatively independent of dynamic quenching by paramagnetic ions. The rate limiting step in benzo(a)pyrene uptake appears to be a first order process not controlled by diffusion. Signal enhancement upon successive increments of liposomes decreases as if it is dependent on the number of free microcrystals in solution.