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Herein, the assessment of interactions between a non-ionic surfactant (NIS) triton X-100 (TNX-100) and a globular protein bovine serum albumin (BSA) was explored through the determination of clouding nature in aqueous solution of sodium salts (Na-salts). Sodium chloride (NaCl), sodium acetate (NaOAc), sodium carbonate (Na2CO3), sodium oxalate (Na2Oxal), sodium sulphate (Na2SO4), and sodium phosphate (Na3PO4) have been chosen to assess their impacts on the clouding nature of TNX-100 + BSA mixture. The estimated cloud point (CP) values were noticed to be lowered with the enhancement of [Na-salts]. The lessening of CP values has been explained by the salting out effect of anions. The calculated standard Gibbs free energy change ( $ \Delta G_c^o $ Δ G c o ) was positive at all examined conditions which illustrates the nonspontaneity of phase change. The standard enthalpy ( $ \Delta H_c^o $ Δ H c o ) and entropy ( $ \Delta S_c^o $ Δ S c o ) changes exhibited negative values at low contents of aq. Na-salts and positive values at high aq. Na-salts content. These consequences illustrate the presence of electrostatic interactions at low Na-salts concentration and hydrophobic interactions at high Na-salts concentration. Furthermore, enthalpy-entropy parameters were successfully computed and explained with proper clarification. [ABSTRACT FROM AUTHOR]

This study exposes the influence of sodium electrolytes and temperature on the interaction forces between tetradecyltrimethylammonium bromide (TTAB) and antibiotic cefixime trihydrate (CMT). The results highlight the significance of considering temperature (from 300.55 to 320.55 K) and electrolytes (NaBr, Na2SO4, Na3PO4, and CH3COONa (NaOAc)) effects when designing drug formulations. Conductometric method was utilised to compute and understand physicochemical parameters occurring during drug-surfactant micellization. The addition of sodium electrolytes favours the micellization of the TTAB and CMT system in aq. salts solution (a decrease of CMC was acquired) except at higher NaOAc concentrations. In all the solvents used herein, the CMC values were detected to be increased with the escalation of working temperature. The $ \Delta H_m^o $ Δ H m o and $ \Delta S_m^o $ Δ S m o expose the survival of hydrophobic interaction involving TTAB and CMT drug in aq. medium whereas both electrostatic and hydrophobic interaction are in function in aq. salts medium. As an extension of the thermodynamic assessment, the molar heat capacity $ ({\Delta C_m^0}) $ (Δ C m 0) were estimated and discussed. The thermodynamics of transfer ( $ \Delta G_{m,tr}^0 $ Δ G m , tr 0 , $ \Delta H_{m,tr}^0 $ Δ H m , tr 0 , and $ \Delta S_{m,tr}^0 $ Δ S m , tr 0 ) and enthalpy-entropy compensation parameters for TTAB + CMT micelles were also analysed. This comprehension of drug-surfactant interaction holds utmost significance in the development of efficient drug formulations and the optimisation of drug delivery techniques. [ABSTRACT FROM AUTHOR]

In this investigation, the supramolecular interaction between a surfactant- tetradecyltrimethylammonium bromide (TTAB) and an antidiabetic drug metformin hydrochloride (MNH) was studied in the presence of some additives (alcohols/urea). The conductometric analysis as a function of surfactant concentration was used to assess the critical micelle concentration (CMC) of TTAB + MNH mixed system. The effect of a gradual change of temperature on CMC within a certain range (298.15–318.15 K) was monitored to assess the thermodynamic nature of micellisation process. In addition, estimation of thermodynamic parameters ( Δ G m o , Δ H m o , and Δ S m o ) and the determination of the degree of counter ion binding (β) give insight into the relative viability of a micellisation process. The values of Δ G m o were negative in all the mixed solvents studied and this was dependent on the chain length of the used alcohols. The thermodynamic parameters of transfer for shifting the micelles from aq. medium to aq. alcohols media and enthalpy-entropy compensation were also computed, compared with literature values and discussed with appropriate reasoning. Several supramolecular forces, including H-bonds, dipole–dipole, ion-dipole, hydrophobic, and electrostatic interactions, were recommended for the aggregation of the TTAB + MNH system. [ABSTRACT FROM AUTHOR]