Synergistic effect of an antipsychotic drug chlorpromazine hydrochloride with pluronic triblock copolymer: A physicochemical study

Chlorpromazine is a psychiatric medication that belongs to the class of drugs called phenothiazine antipsychotics. It works by helping to restore the balance of certain natural substances in the brain. In the current study, the micellization behavior of chlorpromazine hydrochloride (CPZ) drug with Pluronic F-127 in the absence/presence of 0.1 M NaCl at 298 K temperature, has been studied. Tensiometric profile, for pure and mixtures of CPZ + F-127, generally consists of two breaks, whereas a single break is presents in pure CPZ tensiometric isotherm. Various bulk and interfacial parameters, such as critical micelle concentration (cmc), interaction parameter (13), maximum surface excess concentration (Pi(max)), effectiveness of surface tension reduction (Pi(cmc)), and other surface parameters at the interface have been estimated using a surface tension technique. Theories of Clint, Rosen, and Rubingh have been used to determine the theoretical cmc, interaction between amphiphiles at interface and micellar state of aggregation, and the composition of aggregates. The experimental cmc values of the mixed systems are lower than that of ideal one (cmc(ideal)) over the entire mole fraction range of CPZ. A negative departure of cmc values from the ideal indicate that the mixed micelle formation occurs due to favorable mixing (synergistic interactions) in the mixed states. Several thermodynamic parameters have also been predicted from those theories. The interaction between the CPZ and Pluronic F-127 was also determined by extensive steady-state fluorescence measurements. (C) 2018 Elsevier B.V. All rights reserved.