Aqueous amphiphilic drug (amitriptyline hydrochloride)-bile salt mixtures at different temperatures

The mixing behavior of amphiphilic drug amitriptyline hydrochloride (AMT) with bile salts (NaC, NaDC, NaTC) was studied at different compositions and temperatures by conductometry. Rubingh's, Motomura's and Clint's approaches were used to analyse the behavior. The obtained results indicate attractive interactions among the two components upon mixing. The experimentally obtained critical micelle concentration (cmc) values are always lower than ideal cmc values. Increase in temperature gives a peaked behavior to cmc. Micellar mole fraction (X-1 and X-1(m)) values show that the contribution of bile salts in mixed micelles increases with the increase in concentration of these salts. (C) 2011 Elsevier B.V. All rights reserved.