SOLUBILITY ENHANCEMENT TECHNIQUES: A REVIEW

Solubility is the property of a solute to dissolve in solvent to form a homogeneous solution. Solubility is the amount of solute that goes in to the solvent to form solution at given conditions of temperature, pressure and pH. Solubility is one of the important parameter to achieve the desired concentration of drug to the systemic circulation for it’s pharmacological response (Bioavailability). Low aqueous solubility is the major problem associated with poorly water soluble drugs. Any drug to be absorbed must be present in the form of solution at the site of absorption. Water is the solvent of choice for liquid pharmaceuticals formulations. Most of the drugs are weakly acidic or weakly basic with poor aqueous solubility. This review put the light on various techniques used for improving solubility of poorly water soluble drugs. These techniques includes physical and chemical modifications like particle size reduction, micronization, solid dispersions, complexation, self-emulsification, inclusion complexes, prodrug and salt formation.