CO-CRYSTALLIZATION TECHNIQUE ITS RATIONALE AND RECENT PROGRESS

Majority of drugs marketed world wide is administered by oral route. Nearly 40% of the new molecular entities coming from discovery were never brought to the market because of biopharmaceutical issues like low solubility, low dissolution rate, low permeability and first-pass metabolism. There are various methods to improve the dissolution/bioavailability of poorly soluble drugs including Pro-drug approach, Salt synthesis, and Particle size reduction, Complexation, Change in physical form, Solid dispersions & Spray drying. Salt formation is one of the most frequently used approaches to improve physiochemical properties of moieties which involve formation of ionic bonds. Co-crystallization is a method of formation of mainly hydrogen bond between the drug molecule and co-former so API regardless of acidic, basic, or ionisable groups could potentially be co- crystallized. Cocrystallization can improve physiochemical properties like solubility, dissolution rate, chemical stability and melting point. Interactions which are responsible for the formation of co-crystals include hydrogen bonding, π-stacking, and Van der Waals forces. The article gives a brief review on the co-crystallization, their method of synthesis, its importance as an alternative over salt formation, Characterization and applications.