ABSTRACT:
The solubility phenomenon of dissolution of solute in solvent to give a homogenous system, is one of the important parameters to achieve desired concentration of drug in systemic circulation for desired pharmacological response. More than 40% new chemical entities (NCEs) developed in pharmaceutical industry are practically insoluble in water, so solubility enhancement is necessary. The ability to increase aqueous solubility can thus be a valuable aid to increasing efficiency and/or reducing side effects for certain drugs. This is true for parenterally, topically and orally administered solutions. Bioavailability depends on several factors, drug solubility in an aqueous environment and drug permeability through lipophilic membranes being the important ones. This appraisal addresses the concept of selection of solubility improving method depends on drug property, site of absorption, and required dosage form characteristics and also obliging to improve the solubilization and bioavailability of poorly soluble drugs by using various approaches like physical modification’s such as particle size reduction, modification of the crystal habit like polymorphs, amorphous form and co crystallization, drug dispersion in carriers, complexation. Chemical Modifications like change of pH, use of buffer, salt formation. Miscellaneous Methods like cosolvency, cocrystallisation, hydrotrophy, and novel techniques. This appraisal also involves new techniques, approaches and applications.