Aggregation behavior and thermodynamic parameters of biosurfactants (NaC/NaDC) in aqueous medium of Emtricitabine and Lamivudine (anti-HIV drugs)

Abstract

This paper investigates the interactions and aggregation behavior of biosurfactants, sodium cholate (NaC) and sodium deoxycholate (NaDC) in aqueous solutions of Emtricitabine and Lamivudine (anti-HIV drugs). The study uses conductometry and UV–visible spectroscopy techniques to evaluate the critical micelle concentration (CMC) at different temperatures ranging from 298.15 K to 313.15 K with a variation of 5 K. The temperature dependence of the CMC was examined, and the stability of micelles was analyzed in light of the hydrophobic-hydrophilic interactions involved in this system. The CMC obtained from both the methods are in agreement. Various thermodynamic parameters, such as ∆ H m 0 ${\increment}{H}_{m}^{0}$ , ∆ S m 0 ${\increment}{S}_{m}^{0\hspace{0.17em}}$ and ∆ G m 0 ${\increment}{G}_{m}^{0}$ have been estimated using a “pseudo-phase separation model” to understand the contribution of the chemical and de-solvation part in the micellization process. Furthermore, the enthalpy-entropy compensation plots validate the micellar stability of the studied systems.