Department of Chemistry, Josip Juraj Strossmayer University of Osijek, F. Kuhača 20, HR-31000 Osijek, Croatia.
Talanta. 2011 Jan 15;83(3):789-94. doi: 10.1016/j.talanta.2010.10.046. Epub 2010 Nov 5.
A sensitive potentiometric surfactant sensor based on a highly lipophilic 1,3-didecyl-2-methyl-imidazolium cation and a tetraphenylborate (TPB) antagonist ion was used as the end-point detector in ion-pair potentiometric surfactant titrations using sodium TPB as a titrant. Several analytical and technical grade cationic and ethoxylated nonionic surfactants (EONS) and mixtures of both were potentiometrically titrated. The sensor showed satisfactory analytical performances within a pH range of 3-10 and exhibited satisfactory selectivity for all CS and EONS investigated. Ionic strength did not influence the titration except at 0.1M NaCl, in which a slight distortion of the second inflexion corresponded with the nonionic surfactant. Two-component combinations of four CS and three EONS were potentiometrically titrated using the sensor previously mentioned as the end-point detector. The quantities of the surfactants varied between 2 and 6 μmol for CS and 2.50 and 7.50 μmol for EONS. The known addition methodology was used for determination of the surfactant with considerably lower concentration in the mixture. Three commercial products containing cationic surfactants as disinfectants and nonionic surfactants were potentiometrically titrated, and the results for both type of surfactants were compared with those obtained with standard conventional methods.
一种基于高亲脂性 1,3-二癸基-2-甲基-咪唑阳离子和四苯硼酸盐（TPB）反离子的敏感电位型表面活性剂传感器，被用作离子对电位滴定法中使用 TPB 钠盐作为滴定剂的终点检测器。对几种分析级和工业级阳离子和乙氧基化非离子表面活性剂（EONS）以及两者的混合物进行了电位滴定。该传感器在 pH 3-10 范围内表现出令人满意的分析性能，对所有研究的 CS 和 EONS 均表现出令人满意的选择性。除在 0.1M NaCl 中离子强度不会影响滴定，在该条件下，第二个拐点的轻微扭曲与非离子表面活性剂相对应。使用上述传感器作为终点检测器，对四种 CS 和三种 EONS 的两个二元混合物进行了电位滴定。CS 的浓度范围为 2-6 μmol，EONS 的浓度范围为 2.50-7.50 μmol。采用已知的添加法测定混合物中浓度较低的表面活性剂。对含有阳离子表面活性剂作为消毒剂和非离子表面活性剂的三种商业产品进行了电位滴定，并将两种类型的表面活性剂的结果与使用标准常规方法获得的结果进行了比较。
