A Review on Solubility Enhancement Using Hydrotropic Phenomena

Solubilization of poorly water-soluble drugs has been a very important issue in screening studies of new chemical entities as well as formulation research. Various techniques are employed to enhance the aqueous solubility of poorly water-soluble drugs and hydrotropic solubilisation is one of them. A hydrotrope is a compound that solubilises hydrophobic compounds in aqueous solution. The problem of emulsification, which is normally encountered with conventional surfactant solutions are not found with hydrotrope solutions. Easy recovery of the dissolved solute and the possible reuse of hydrotrope solutions make this method the most effective one particularly at industrial levels. Besides, the advantage of certain properties like the solvent character independent of pH, high selectivity, non-flammability, cheap and easy availability of hydrotropes, makes this technique superior to other solubilization methods. To solubilize water insoluble drugs especially in case of oral formulation, solubility remains a critical factor, so for in this review various solubility enhancement techniques are highlighted and a brief review of hydrotropy and its preparation are discussed.