Investigation of drug release from carnauba wax matrices: a case study of propranolol hydrochloride

Abstract

A study was carried out to assess the effect of carnauba wax particle size on sustained release characteristics, the effect of drug loading on release and the kinetics of propranolol hydrochloride release from carnauba wax matrices.

The results obtained showed that small particles (180 250 µ m) of carnauba wax had superior release on sustaining characteristics than larger particles (>250 µ m). Drug release from small particles was best explained by either the Higuchi mechanism or first order kinetics. In general, as particle size increased, zero order kinetics seemed to contribute to the release mechanism. There was also an increase of drug release as the drug loading was increased. This increase in drug release was probably due to increased porosity.

Keywords: carnauba wax, sustained release, particle size and kinetics

East and Central African Journal of Pharmaceutical Sciences Vol. 7 2004: 3-5