Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia.
PLoS One. 2019 Feb 6;14(2):e0211077. doi: 10.1371/journal.pone.0211077. eCollection 2019.
In the current study, we have examined the interaction amongst an antidepressant drug amitriptyline hydrochloride (AMH) and ethane-1, 2-diyl bis(N,N-dimethyl-N-cetylammoniumacetoxy) dichloride (16-E2-16, a green gemini surfactant) through tensiometric and fluorimetric techniques in aqueous/electrolyte/urea solutions. Significant variations are observed in the various evaluated parameters in the present study. Gemini 16-E2-16 has outstanding surface properties along with a much lower cmc value, demonstrating very little toxicity as well as considerable antimicrobial activity. The cmc values of mixtures decrease through increase in mole fraction (α1) of 16-E2-16, which specifies the nonideality of the solution mixtures, along with demonstrating the occurrence of mixed micellization too. Negative βRub values signify on the whole attractive force of interaction between constituents of mixed micelles. Owing to the incidence of electrolyte NaCl (50 mmol.kg-1), lowering of the micelles' surface charge happens, resulting in aggregation taking place at lower concentration while the presence of urea (NH2CONH2) halts micellization taking place, which means the cmc value increases in the attendance of urea. The [Formula: see text] values for all systems were negative along with the presence of electrolyte/urea. The excess free energy (Gex) of studied mixed systems was also estimated and found to be negative for all the systems. Using the fluorescence quenching method, the micelle aggregation number (Nagg) was evaluated and it was found that the contribution of gemini surfactant was always more than that of the AMH and their value enhances in the existence of electrolyte while decreasing in the attendance of NH2CONH2 in the system. In addition, other fluorescence parameters such as micropolarity (I1/I3), dielectric constant (Dexp) as well as Stern-Volmer binding constants (Ksv) of mixed systems were evaluated and the results showed the synergistic performance of the AMH + 16-E2-16 mixtures. Along with tensiometric and fluorimetric techniques, FT-IR spectroscopy was also engaged to reveal the interaction among constituents.
在目前的研究中，我们通过张力和荧光技术研究了抗抑郁药盐酸阿米替林 (AMH) 和乙烷-1,2-二基双 (N,N-二甲基-N-十六烷基铵乙氧基) 二氯 (16-E2-16，一种绿色双子表面活性剂) 在水/电解质/尿素溶液中的相互作用。在本研究中观察到各种评估参数有显著变化。双子 16-E2-16 具有出色的表面性能，同时具有较低的 cmc 值，表明毒性很小，同时具有相当的抗菌活性。混合物的 cmc 值随 16-E2-16 摩尔分数 (α1) 的增加而降低，这表明溶液混合物的非理想性，同时也表明混合胶束化的发生。负的βRub 值表示混合胶束中各成分之间的总体相互吸引力。由于电解质 NaCl (50 mmol.kg-1) 的存在，降低了胶束的表面电荷，导致在较低浓度下发生聚集，而尿素 (NH2CONH2) 的存在阻止了胶束化的发生，这意味着 cmc 值在尿素存在下增加。所有系统的 [Formula: see text] 值均为负，且存在电解质/尿素。还估计了所有系统的过剩自由能 (Gex)，发现所有系统的值均为负。使用荧光猝灭法评估了胶束聚集数 (Nagg)，发现双子表面活性剂的贡献始终大于 AMH 的贡献，并且在存在电解质时它们的值增加，而在系统中存在 NH2CONH2 时则降低。此外，还评估了混合系统的其他荧光参数，如微极性 (I1/I3)、介电常数 (Dexp) 和 Stern-Volmer 结合常数 (Ksv)，结果表明 AMH+16-E2-16 混合物具有协同作用。除了张力和荧光技术外，还使用傅里叶变换红外光谱 (FT-IR) 来揭示成分之间的相互作用。
