Department of Chemistry, Avignon University, CNRS, UMR5247 CBSA/IBMM, Avignon, France.
Department of Chemistry, Avignon University, INRAE, UMR408 SQPOV, Avignon, France.
Electrophoresis. 2022 Dec;43(23-24):2290-2301. doi: 10.1002/elps.202200075. Epub 2022 Jul 10.
Affinity capillary electrophoresis was used for the simultaneous measurement of the pK values and of the binding constants relative to the encapsulation of naturally occurring phenolic acids (rosmarinic and caffeic acids) with cyclodextrins. A thorough study as a function of pH and temperature was coupled to a detailed statistical analysis of the resulting experimental data. A step-by-step curve fitting process was sufficient for obtaining individual binding constant for each experimental condition, but the influence of temperature remained unclear. A quantitative and qualitative gain was then obtained by supplementing this initial analysis with global multiparameter optimization. This leads to the estimation of both entropy and enthalpy of reaction and to the full description of the binding reactions as a function of pH and temperature. The encapsulation was shown to be very sensitive to pH and temperature, with optimal complexation occurring at low pH and low temperature, gaining up to a factor of 3 by cooling from 36 to 15°C, and up to a factor of 10 by lowering the pH from 7 to 2.
亲和毛细管电泳用于同时测量 pK 值和与环糊精包合的天然酚酸（迷迭香酸和咖啡酸）的结合常数。pH 值和温度的综合研究与对所得实验数据的详细统计分析相结合。对于每个实验条件，逐步曲线拟合过程足以获得单个结合常数，但温度的影响仍不清楚。然后，通过用全局多参数优化补充此初始分析，获得了定量和定性的增益。这导致可以估计反应的熵和焓，并全面描述 pH 值和温度下的结合反应。包合对 pH 值和温度非常敏感，在低 pH 值和低温下最佳络合，从 36°C 冷却到 15°C 可提高近 3 倍，从 pH 值 7 降低到 2 可提高近 10 倍。
