A Comparison of Interaction and Solvent Deposition Mixing

Abstract

The mixing of microingredients with diluents may be conducted by various methods. The purpose of this report is to compare the uniformity of mixing of finely powdered reserpine after mixing by an interactive and a solvent deposition method. Reserpine was used in concentrations of 0.25% with Avicel PH 102 and Sorbit Instant as carrier materials. The uniformity of the mixtures was compared by coefficients of variation (CV) of the content of powder or tablet samples. The dissolution of powder samples was measured in a rotating bottle apparatus. Interactive mixing with Avicel produced samples with larger variation in reserine content compared to solvent deposition. The variation in content was not significantly different when the drug was mixed interactively or by solvent deposition on Sorbit. Smaller coefficients of variation in content were observed for tablet samples compared to powder samples in most cases. The CVs obtained with powder samples for all the mixtures. except for solvent deposition on Avicel, were larger than 5% and would therefore not comply with pharmaceutical content uniformly standards. The CVs for all tablet samples, however, were less than 5%, and based on these results all the mixtures were sufficiently mixed so that the tablets complied with content uniformity standards. The dissolution profiles were not influenced by mixing method.