Crystal Engineering and its Chemistry: An Architectural Approach for Cocrystallization

Background: In the field of crystal engineering, cocrystallization is a unique technique by the help of which physicochemical properties like melting point, solubility, dissolution, etc of the APIs can be modified without changing the intrinsic structure of APIs. Objective: Crystal packing of a solid is modified by crystal engineering techniques which involve modification of intermolecular interactions that help to regulate breaking and creation of noncovalent bonds. Non-covalent interactions such as hydrogen bonding, van der Waals forces, π-π stacking are primarily responsible for the formation of cocrystals. Cocrystals are solid crystalline materials consisting of two or more molecules present in the similar crystal lattice. It is a method of formation of mainly hydrogen bonds between the drug molecule and coformer. This technique can be applied to almost all APIs which have low aqueous solubility. There are several active pharmaceutical ingredients available, which have therapeutic efficacy against several lifethreatening diseases. Among those APIs, which have poor aqueous solubility and low oral bioavailability (BCS class II and class IViv), cannot be efficiently developed into a suitable dosage form. Conclusion: Therefore, this survey gives a united record of the reasoning for plan of cocrystals, past endeavors, later improvements and future viewpoints for cocrystallization research which will be incredibly helpful for the formulation scientists of the pharmaceutical industry.