Abstract
Herein, the interaction between Tween-80 (Tw-80) and antibiotic drug lomefloxacin hydrochloride (LMFH) has been studied through the cloud point (CP) measurement of Tw-80 + LMFH mixtures in the absence/attendance of electrolytes. Tw-80 is used for different formulations of drugs and foods. LMFH is widely prescribed for the treatment of numerous bacterial infections. The cloud point (CP) values of Tw-80 + LMFH mixture were determined and found to reduce with the augmentation of concentration of LMFH. The occurrence of salts reduces the CP of the Tw-80 + LMFH mixture which further enhances with an increase of salt concentration. The effectiveness of electrolytes in decreasing CP of Tw-80 + LMFH mixture was obtained to be followed the order: CPNaCl < CPNa2SO4 < CPNa3PO4. 12 H2O which reveal that Na3PO4. 12 H2O is the most effective CP suppressor. The Gibbs free energy (∆Gco) value was achieved positive in entire systems and the positive ∆Gco value was lowered in the salt medium. The ∆Gco values were also dwindled through the augmentation of LMFH/electrolytes content in the solution. The enthalpy (∆Hco) and entropy (∆Sco) value of this system was found to be negative which drops with the rise of LMFH/electrolytes content. In addition, different thermodynamic properties of transfer along with entropy-enthalpy compensation was computed to clarify the interaction between Tw-80 and LMFH.
•Interaction of Tw-80 with lomefloxacin hydrochloride (LMFH) was studied.•Cloud points (CP) depend on the additive concentrations.•Effect of three sodium salts on the CP of surfactant is investigated.•Clouding of Tw 80 + LMFH mixture is nonspontaneous process.•Thermodynamic properties of Tw-80 + LMFH system are determined and explained.