Zook Justin M, Langmaier Jan, Lindner Ernő
Department of Biomedical Engineering, The University of Memphis, Memphis, TN 38152, USA.
Sens Actuators B Chem. 2009 Mar 2;136(2):410-418. doi: 10.1016/j.snb.2008.12.047.
Lipophilic background electrolytes consisting of a lipophilic cation and a lipophilic anion, such as tetradodecylammonium tetrakis(4-chlorophenyl) borate (ETH 500), or bis(triphenylphosphoranylidene) ammonium tetrakis[3,5bis(trifluoromethyl) phenyl] borate (BTPPATFPB) are incorporated into the membranes of ion-selective electrodes (ISEs) to improve the detection limit and selectivity of the electrodes and decrease the resistance of the sensing membrane. In this work, spectroelectrochemical microscopy (SpECM) is used in conjunction with chronopotentiometry to quantify the effects of a lipophilic background electrolyte on the concentration profiles induced inside current-polarized membranes and on the measured voltage transients in chronopotentiometric experiments. In agreement with the theoretical model, the lipophilic background electrolyte incorporated into o-NPOE or DOS plasticized membranes decreases the membrane resistance and thus the contribution of migration in the overall transport across ion-selective membranes. Consequently, it has a significant influence on the changing concentration profiles of the ion-ionophore complex during chronopotentiometric experiments.
由亲脂性阳离子和亲脂性阴离子组成的亲脂性背景电解质，如四（4-氯苯基）硼酸十四烷基铵（ETH 500）或四[3,5-双（三氟甲基）苯基]硼酸双（三苯基磷亚基）铵（BTPPATFPB），被纳入离子选择性电极（ISE）的膜中，以提高电极的检测限和选择性，并降低传感膜的电阻。在这项工作中，光谱电化学显微镜（SpECM）与计时电位法结合使用，以量化亲脂性背景电解质对电流极化膜内诱导的浓度分布以及计时电位实验中测量的电压瞬变的影响。与理论模型一致，纳入邻硝基苯基辛醚（o-NPOE）或二辛基癸二酸酯（DOS）增塑膜中的亲脂性背景电解质降低了膜电阻，从而降低了迁移在跨离子选择性膜的整体传输中的贡献。因此，它对计时电位实验期间离子-离子载体复合物浓度分布的变化有显著影响。
