Nabi Arshid, Jesudason Christopher G, Sabir Jamal S M, Kamli Majid Rasool
Department of Chemistry, University of Malaya, Kuala Lumpur 50603, Malaysia.
Department of Biological Sciences, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
Pharmaceuticals (Basel). 2023 Aug 22;16(9):1187. doi: 10.3390/ph16091187.
This study was aimed at establishing the interactions prevailing in an anionic surfactant, sodium dodecyl sulfate, and dopamine hydrochloride in an alcoholic (ethanol) media by using volumetric, conductometric, and tensiometric techniques. Various methods were utilized to estimate the critical micelle concentration (cmc) values at different temperatures. The entire methods yielded the same cmc values. The corresponding thermodynamic parameters viz. the standard free energy of micellization (Gmico), enthalpy of micellization (Hmico), and entropy of micellization (Smico) were predicted by applying the pseudo-phase separation model. The experimental density data at different temperatures (298.15 K, 303.15 K, 308.15 K, and 313.15 K) were utilized to estimate the apparent molar volumes (Vϕo) at an infinite dilution, apparent molar volumes (Vφcmc) at the critical micelle concentration, and apparent molar volumes (ΔVφm) upon micellization. Various micellar and interfacial parameters, for example, the surface excess concentration (Γmax), standard Gibbs free energy of adsorption at the interface (ΔGoad), and the minimum surface area per molecule (Amin), were appraised using the surface tension data. The results were used to interpret the intermolecular interactions prevailing in the mixed systems under the specified experimental conditions.
本研究旨在通过体积法、电导法和表面张力法，确定在酒精（乙醇）介质中，阴离子表面活性剂十二烷基硫酸钠与盐酸多巴胺之间存在的相互作用。采用多种方法估算不同温度下的临界胶束浓度（cmc）值。所有方法得到的cmc值相同。通过应用假相分离模型预测了相应的热力学参数，即胶束化标准自由能（Gmico）、胶束化焓（Hmico）和胶束化熵（Smico）。利用不同温度（298.15 K、303.15 K、308.15 K和313.15 K）下的实验密度数据，估算无限稀释时的表观摩尔体积（Vϕo）、临界胶束浓度下的表观摩尔体积（Vφcmc）以及胶束化时的表观摩尔体积（ΔVφm）。利用表面张力数据评估了各种胶束和界面参数，例如表面过剩浓度（Γmax）、界面吸附标准吉布斯自由能（ΔGoad）和每分子最小表面积（Amin）。结果用于解释在特定实验条件下混合体系中存在的分子间相互作用。
