Nanoparticle formation from probucol/PVP/sodium alkyl sulfate co-ground mixture

Nanoparticles of a poorly water-soluble drug, probucol, have been obtained by co-grinding with PVP and SDS. The purpose of this study was to investigate the effect of the alkyl chain length of sodium alkyl sulfates (CnS, n = 6, 8, 12, 16 and 18) on probucol nanoparticle formation. From the results of particle size determination and quantitative measurement of nanoparticle fraction of probucol by HPLC, it was found that the alkyl chain length of the sodium alkyl sulfate affected the probucol nanoparticle formation. The efficiency, based on the quantitative determination of nanoparticles, was in the order: C18S > C16S > C12S > C8S > C6S. Probucol nanoparticles of less than 800 nm were effectively produced (more than 95%) with the increase of the amount of surfactants. 13C solid-state NMR of co-ground mixtures showed a new peak originating from the probucol interaction with PVP together with the existence of probucol crystal peaks. Excess amounts of surfactants were expected to play an important role for stabilizing the probucol nanoparticles in the suspension via the electrostatic repulsive effect.