Alva-Ensastegui J C, Palomar-Pardavé M, Romero-Romo M, Ramírez-Silva M T
Universidad Autónoma Metropolitana - Iztapalapa, Departamento de Química, Área de Química Analítica Av. San Rafael Atlixco #186, Col. Vicentina, C.P. 09340 Ciudad de México México
Universidad Autónoma Metropolitana - Azcapotzalco, Departamento de Materiales, Área Ingeniería Materiales Av. San Pablo #180, Col. Reynosa-Tamaulipas, C.P. 02200 Ciudad de México México.
RSC Adv. 2018 Mar 20;8(20):10980-10986. doi: 10.1039/c8ra01213j. eCollection 2018 Mar 16.
Quercetin spectrofluorometric quantification was carried out in aqueous media (pH 7) using micelles of surfactants, namely: CTAB, SDS and TX100 as promoters of quercetin fluorescence, having a critical micelle concentration, CMC, of: 0.94 ± 0.03, 7.7 ± 0.6 and 0.18 ± 0.3 mM, respectively, measured through UV-Vis spectrophotometry. The thermodynamic binding constant, , for the quercetin-surfactants' micelles supramolecular complex was estimated to be (log(/M)) = 2.87 ± 0.02, 2.78 ± 0.04 and 2.80 ± 0.04, respectively, from fluorescence spectrophotometry. With the aid of these parameters it was possible to construct species distribution diagrams and choose the experimental conditions where quercetin can be quantified in aqueous media from fluorescence measurements. The best lowest limit of detection (0.244 ± 0.092) μM was achieved with CTAB micelles while the best sensitivity (2.919 ± 0.054) M corresponded to SDS.
槲皮素的荧光光谱定量分析是在水介质（pH 7）中进行的，使用表面活性剂胶束，即十六烷基三甲基溴化铵（CTAB）、十二烷基硫酸钠（SDS）和聚氧乙烯辛基苯基醚（TX100）作为槲皮素荧光的促进剂，通过紫外可见分光光度法测得其临界胶束浓度（CMC）分别为：0.94±0.03、7.7±0.6和0.18±0.3 mM。通过荧光分光光度法估计，槲皮素 - 表面活性剂胶束超分子复合物的热力学结合常数（log(K/M)）分别为2.87±0.02、2.78±0.04和2.80±0.04。借助这些参数，可以构建物种分布图，并选择能够通过荧光测量在水介质中对槲皮素进行定量分析的实验条件。使用CTAB胶束时实现了最佳最低检测限（0.244±0.092）μM，而最佳灵敏度（2.919±0.054）M对应于SDS。
