Influence of Water-soluble polymers on Epalrestat ternary complexation by kneading

Abstract

The study reported in this current work objected to demonstrate the formation of binary and ternary inclusion complexes of Epalrestat (EP), a poorly water-soluble acidic type drug, with s-cyclodextrin (CD) and with water-soluble polymers PVP K30 and HPMC E4. The solid systems of EP with s-CD and water-soluble polymers were obtained by kneading and characterized for phase solubility, saturation solubility, dissolution, stability studies. FTIR, DSC, PXRD and SEM data indicated the positive influence of s-CD and hydrophilic polymers on EP solubility and dissolution. Phase solubility studies were carried out to evaluate the solubilizing power of CD, with regards to EP in combination with water-soluble polymers, and to determine the apparent stability constants (Ks) and complexation efficiency (CE) of the complexes. Phase solubility studies showed AL (linear) type of solubility curve for the ternary complexes it also showed amelioration in Ks value for ternary complexes. The CE of s-CD towards EP was promoted by water-soluble polymers signifying its use as a ternary component. The dissolution rate of EP and solubility were undoubtedly improved by complexation with s-CD as compared to model drug EP alone. Ternary complexes incorporated with PVP K 30 and HPMC E4 proved better than binary complex. Hence, the water-soluble carrier could be exploited as a ternary component to improve the solubility of EP via s-CD complexation.