Preparation, characterization and pharmaceutical application of linear dextrins: IV. Drug release from capsules and tablets containing amylodextrin

Abstract

Linear dextrin (amylodextrin) and its soluble fraction were investigated for their suitability to enhance diazepam release from capsules and tablets. Drug release was analyzed in the USP XXI paddle apparatus and performed in phosphate buffer pH 6.8, with and without α-amylase, and in 0.1 N HCl solution. Diazepam release from capsules was slightly increased on application of amylodextrin, either as a filler in a physical mixture or as a carrier for solid dispersion of the drug, as compared to the release from capsules containing drug only. The limited increase in drug dissolution is caused by the limited solubility of amylodextrin. Application of the soluble fraction of amylodextrin therefore showed faster drug release. In contrast, the limited solubility and non-disintegrating behaviour of amylodextrin appeared to be extremely suitable properties to apply this excipient in the formulation of programmed release systems.