Morphology control of eprosartan crystals via polymer-directed crystallization

Abstract

Improving the stability, processability and bioavailability of drug crystals is important during the development of most drugs. In traditional crystal engineering, different crystallization conditions are used to tailor the properties of crystals, often improving one property at the cost of another, or simply optimizing both properties. The influence of soluble polymers on the particle morphology of crystals during the crystallization of eprosartan was investigated to explore the possibility of improving the properties of the drug crystals. The presence of polyethylenimine (PEI) during the crystallization of eprosartan induced the self-assembly of small primary crystals into larger aggregates without changing the crystal polymorph. In particular, spherical aggregates of an ordered structure were obtained when eprosartan was crystallized by changing the pH from 12 to 4.2 in the presence of PEI. This technique of polymer-directed crystallization is promising for the property engineering of drug crystals, which has been limited by a few crystallization variables to date. © 2015, The Korean Society of Pharmaceutical Sciences and Technology.