Aggregation by stacking of a drug in aqueous solution studied by means of light scattering and ultrasonic relaxation

Abstract

The aggregation of the drug tacrine hydrochloride in aqueous solution has been studied by means of light scattering and ultrasonic relaxation. The concentrations of the aggregated species are calculated for various total concentrations. Evidence is presented to suggest that the mechanism of association involves stacking and that the rate of association is diffusion controlled. Various kinetic models are discussed with particular reference to those which involve concentration-dependent rate coefficients.