Solubility and Solubilization: For Formulation Scientists
Author (s): Anjan Kumar Mahapatra
Number of new drug candidates produced in the past decade shows low soluble characteristics. This has promoted the interest in so-called drug-ability of the new drugs, i.e., formulations which shall make such drugs bio-available. Low soluble drugs (BCS class II) and their enhancement of solubility through various approaches is a well-known but still a big challenge to formulation scientists. In accordance to the Noyes-Whitney equation for low soluble drugs dissolution kinetics and solubility are particle size dependent, while the wetting properties of the used polymer may also play an important role. Here it is focused on the ways and means of enhancement of solubility hence dissolution rate. Here it is discussed on different solubilization techniques covering; BCS, chemical modification, physical modification, alteration of solvent system and carrier systems under solubilization. Various polymers being used as hydrophilic carriers for drug solubilization is outlined.
Keywords: Solubility enhancement, dissolution process, BCS class II, hydrophilic carriers.