Solubility Enhancement Techniques for BCS Class-II and IV Drugs Using Co-Crystalization Approach

Abstract

Solubility is the property of substance defined as the dissolution of solute in to solvent in desired homogenous system. It is the parameter by which the concentration in systemic circulation is achieved for required pharmacological effect or action of the drug in living organisms. For the development of the formulation of generic drugs and the new chemical entities is affected by the solubility , low aqueous solubility is one of the problems regarding with this . in the water more than 40% of the New Chemical entities (NCEs) is partially insoluble . solubility is the major concern for the scientists for the formulation and development of the drugs . for the absorption of the drug substances to the site of the absorption is must be in the form of the solution for good pharmacological effects. There are many techniques are use for the enhancement of the solubility of the drug in the systemic circulation for greater p’cological effect . the methods like physical modification(particle size reduction, micronization, nanosuspension, cryogenic techniques), chemical modification(ph change, use of buffer, salt formation, complexation, derivatization) and other miscellaneous methods (super critical fluid, use of excipients like surfactants, hydrotropy, novel excipients, solubilizers, co solvents etc….) . the selection of the method for enhancing the solubility is the depends on the various factors like properties of the drug molecule , dosage form of the drug , site of action or the site of absorption of the drug and also bioavailability . the purpose of this review is to describe the solubilization techniques for the drug by improving bioavailability and effective absorption (particularly for BCS class drugs). Co-crystallization is the chemical modification technique for the solubility enhancement, particularly for BCS class-II & IV drugs which have barriers in drug delivery or absorption due to low solubility. Co-crystallization is the approach for the modifying the crystal structure of the drug substance which leads to change in properties of drugs & its pharmacological action by enhancing the solubility of the drug molecule. There are different techniques of Co-crystallization like Grinding, solvent evaporation, Hot melt extrusion, slurry Co-crystallization, Sonocrytallization is used for the Enhancing the solubility, bioavailability & physicochemical properties of API(active pharmaceutical ingredients)