Characterization of amorphous solid dispersions: An update

Amorphous solid dispersions (ASDs) are a promising formulation approach to improve the solubility, dissolution rate, and bioavailability of poorly water-soluble drugs. ASDs have complicated physicochemical properties due to the various formulations and processes used to produce them. These properties influence their physical stability, so it is important to develop comprehensive and effective characterization techniques for ASDs. Our understanding of the properties of ASDs can be improved through the use of a combination of these techniques. Key factors that affect the properties of ASDs include the glass transition temperature (T-g), molecular mobility, miscibility, and crystallinity. These factors must be evaluated to ensure a stable ASD. In this review, we discuss the most relevant analytical characterization techniques and their applications for the evaluation of ASDs.