Influence of Different Additives on the Clouding Nature and Thermodynamic Behavior of Tween 80 Solution in the Absence and Presence of the Amikacin Sulfate Drug

Herein, the cloud-point (CP) measurements of a nonionic surface-active agent named Tween 80 [poly(oxyethylene) (20) sorbitanmonooleate; Tw 80] were carried out in this study in the absence and attendance of an amikacin sulfate (AS) drug/(AS+ inorganic electrolyte (NaCl, NaNO3 and Na2SO4)). AS drug has been utilized to treat or prevent a wide range of bacterial infections. The measured values of CP in the aqueous phase for Tw 80 were observed in decreasing fashion with an increase in the concentration of surfactant. The obtained values of CP for Tw 80 solution were also noticed to decrease with increasing drug concentration. The determined CP values for (surfactant + drug) mixture were observed to decrease for the electrolytes’ participation with respect to their nonparticipation, and the presence of electrolytes (sodium salts) in declining CP measurement was recorded and followed the order NaCl > NaNO3 > Na2SO4. The ΔGc0 values are found to be positive that denotes the character of clouding is nonspontaneous. The ΔHc0 and ΔSc0 calculations were shown to be negative for the system studied except for the (Tw 80 + H2O) phase. The negative values of ΔHc0 and ΔSc0 decreased with the increment of electrolyte concentration. The thermodynamic parameters of transfer for the studied system were also evaluated and are illustrated in detail.