Gelatinized tapioca starch−magnesium aluminum silicate nanocomposites: Physicochemical characterization and evaluation for modified-release tablets

Abstract

The objectives of this work were to prepare and investigate gelatinized tapioca starch-magnesium aluminum silicate (GTS-MAS) composites for use in modified-release tablets. The dispersions consisting of GTS and MAS with various ratios and %solid content were prepared and dried by spray drying to get the GTS-MAS composites. GTS could molecularly interact with MAS via hydrogen bonding, leading to an enhancement of thixotropic properties in the dispersion and the formation of exfoliated nanocomposites after drying. The GTS-MAS composites presented an elliptical shape with wrinkle shrinkage, powder bulkiness, and poor particle flowability. However, they had better particle flowability and tablet compressibility than the GTS particles. The drug-loaded GTS-MAS tablets provided remarkably higher hardness than the drug-loaded GTS tablets. The shorter disintegration time and the faster drug release of the tablets were found when increasing MAS ratios because the composites with higher MAS ratios displayed higher swelling capacity in both acidic and neutral media. Thus, drug diffusion coupled with swelling/erosion of the gel matrix could retard drug release from tablets. These findings suggested that the GTS-MAS nanocomposites could be employed as a matrix former in tablets intended for modifying drug release.