Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.
Anal Chem. 2021 Nov 9;93(44):14737-14742. doi: 10.1021/acs.analchem.1c03193. Epub 2021 Oct 26.
Classical application of ion-selective membranes is limited to either electrochemical or optical experiments. Herein, the proposed ion-selective membrane system can be used in both modes; each of them offering competitive analytical parameters: high selectivity and linear dependence of the signal on logarithm of analyte concentration, high potential stability in potentiometric mode, or applicability for alkaline solutions in optical mode. Incorporation of analyte ions into the membrane results in potentiometric signals, as in a classical system. However, due to the presence of lipophilic positively charged ions, polymer backbones, full saturation of the membrane is prevented even for long contact time with solution. The presence of both positively charged and neutral forms of conducting polymers in the membrane results in high stability of potential readings in time. Optical signal generation is based on polythiophene particulates dispersed within the ion-selective membrane as the optical transducer. An increase of emission is observed with an increase of analyte contents in the sample.
经典的离子选择性膜应用仅限于电化学或光学实验。在此，所提出的离子选择性膜系统可用于这两种模式；它们各自提供具有竞争力的分析参数：在电位计模式下具有高选择性和信号对分析物浓度对数的线性依赖性，或在光学模式下适用于碱性溶液；在聚合物基质中掺入分析物离子会产生类似于经典系统的电位信号。然而，由于亲脂性带正电荷离子的存在，即使与溶液长时间接触，也会阻止聚合物骨架完全饱和。在膜中同时存在带正电荷和中性形式的导电聚合物，导致电位读数在时间上具有高稳定性。光学信号的产生基于作为光学换能器的分散在离子选择性膜中的聚噻吩颗粒。随着样品中分析物含量的增加，观察到发射强度增加。
