A Recent Review on Bioavailability and Solubility Enhancement of Poorly Soluble Drugs by Physical and Chemical Modifications

Abstract

Solubility is the phenomenon of dissolution of solid in liquid phase to give a homogenous system. Solubility is one of the important parameter to achieve desired concentration of drug in systemic circulation for pharmacological response that is called bioavailability. Therapeutic effectiveness of a drug basically depends upon bioavailability and the solubility of drug moiety. Most of the chemical entities that are being discovered are lipophilic and have poor aqueous solubility. A more than 40% drug suffers from poor water solubility hence new chemical entities developed in pharmaceutical industry are lipophillic and fail to reach the market due to their poor water solubility. Currently number of techniques addressed the enhancement of solubility and dissolution rate of poorly soluble drugs. Water is the solvent of choice for liquid pharmaceutical formulations. Most of drugs weakly acidic and weakly basic with poor aqueous solubility. Hence various techniques are used for the improvement of the solubility of poorly water-soluble drugs include micronization, chemical modification, pH adjustment, solid dispersion, complexation, co‐solvency, micellar solubilization, hydrotropy etc. In this review we concentrated on improvement of the solubility and bioavailability of poorly water soluble drugs by applying various new methods.

Keywords: Solubility, Hydrotropy, Mixed Hydrotropy, Micronization, Co‐Solvency, Micellar Solubilization