Designing Spherical Particles of Arbidol Hydrochloride via Spherical Crystallization: Preparation and Characterization

Arbidol hydrochloride is an antiviral drug and is widely used in pharmaceuticals and daily chemicals. Arbidol hydrochloride crystals usually appear as needles with a relatively large aspect ratio, having poor flow properties, thus further limiting their application. To solve this problem, a ternary solvent system required for spherical agglomeration of Arbidol hydrochloride was successfully screened out by using van der Waals acid–base theory, simulation calculation, and high-throughput experiments. Meanwhile, the effects of BSR (Vbridging liquid/Vsolute), initial concentration, flow rate of antisolvent addition, stirring rate, and crystallization time on the morphology and particle size distribution of spherical particles had been experimentally studied. Characterization results showed that the obtained spherical crystals had a round morphology with better particle size distribution, which could improve the powder performances of the product. Furthermore, the mechanism of spherical agglomeration was proposed, providing new insights into designing spherical crystallization to obtain ideal spherical crystals and enhance powder performance in the future.