Solubility and Stability Advantages of a New Cocrystal of Berberine Chloride with Fumaric Acid

[Image: see text] BBC is a drug with a variety of activities but poor solubility. Cocrystal technology is an effective method to improve the solubility and stability of this type of compound. In this work, the cocrystal of BBC with fumaric acid was obtained at a stoichiometric ratio of 2:1. Studies on stabilities and solubilities were carried out using BBC dihydrate and tetrahydrate as reference materials. Results showed that this new cocrystal did not only significantly improve the dissolution rate of BBC but also highly improved the stability in high humidity and temperature. Given that the cocrystals formed by BBC as the host molecule were few, different techniques were applied for characterization and structural analyses. Moreover, theoretical calculations were performed on weak interactions, such as hydrogen bonding and π–π stacking interactions, which provided the research data for the study of this kind of cocrystal.