ROLE OF HYDROTROPIC SALT SOLUTIONS IN PHARMACEUTICAL RESEARCH: PAST PRESENT AND FUTURE

Hydrotropic solubilization technique is a one of the most potential tool to solubilize poorly water soluble drug. Hydrotropy can be described by the increase in the solubility of a solute by the addition of fairly high concentrations of another solute, may it be an organic compound, salt, or amhiphile. Initially it was proposed for the solubilization of poorly water soluble drug but recently various facets of the technique has been discovered viz. for use in, solid dispersions, parenteral formulation, nanoparticlate delivery and extraction of bioactive materials and many of them are being critically assessed through active research. In this review attempts have been made to compile every aspect of the hydrotropic, its probable mechanism, its utilization in the estimation of poor water soluble drugs in their bulk drug and respective dosage to serve as a better replacement for the hazardous organic solvents like methanol, acetone, DCM, ethers etc which are more commonly used in the analytical estimation. Similarly the technique is also being progressively used in the formulation of poorly water soluble drugs to avoid the use of organic solvents. Salts involved in this technique present certain limitations which confine their use. In order to avoid such limitations of these salts, concept of mixed hydrotropy and mixed solvency has been introduced recently. The same is also discussed in this review.