Micellization Behavior of Antidepressant Imipramine Hydrochloride Drug and Hydrotrope (Sodium Tosylate) Mixtures at Different Compositions and Temperatures in Different Media

The effects of various concentrations of sodium tosylate (NaT) hydrotrope on aggregation phenomena of antidepressant drug imipramine hydrochloride (IH) were investigated at four different temperatures (288.15-303.15 K having a gap of 5 K) in detail in three diverse solvents (aqueous/NaCl/urea (UR)). Various reported theoretical models were applied to evaluate different physicochemical parameters regarding the mixed micellization. Obtained values of critical micelle concentration (cmc) and ideal cmc (cmc(id)) point out the formation of mixed micelles among the constituents. By employing different models, the values of micellar mole fractions (X-1(Rub), X-1(Rd), and X-1(id)) of hydrotrope were computed, and the results show the larger involvement of employed hydrotrope in the solution mixture. The effects of additives, for instance, NaCl and UR, were also investigated on the micellization behavior of a singular and mixed system using conductivity measurement. The employed concentration of salt and UR decreases and increases the cmc of the system, respectively. The obtained interaction parameter (beta) of the studied system is negative in the entire temperature range along with compositions signifying the interactions between the ingredient. The activity coefficients determined by both models forever achieved less than 1 in all cases viewing the nonideality of systems. The different thermodynamic parameters showed the spontaneity in mixed micelle formation in all systems of different media. The activity coefficients were analyzed using the employed models and were found to be less than 1 in entire cases viewing the attractive nonideal behavior.