In this paper, di-tripodal amine calix[4]arene, L1, was successfully synthesized and used as an ion carrier in poly(vinyl chloride) (PVC) membrane electrodes. Compound L1 was employed to demonstrate a new concept in anion sensing by preparing an allosteric PVC membrane that can respond selectively to a certain anion in the presence of a metal effector. Membranes containing compounds L1 and potassium tetrakis(p-chlorophenyl)borate (KTpClPB) as an ionic additive showed Donnan exclusion failure upon measuring the potential (EMF) responses of Cu2+ and responded to the co-anion by giving negative EMF changes, while membranes containing compound L2, an anthracene-based mono-tripodal amine ligand, gave positive potentials to most metal ions. Upon preconditioning of the membranes containing L1 and 75 mol% KTpClPB in CuCl2, the membranes showed the highest selectivity towards thiocyanate with a near Nernstian slope of −59.6 mV decade−1, a 10−5 to 10−2 M linear range, and a detection limit of 4.4 × 10−6 M. The best allosteric membrane can be used in the pH range 3–7 with good reversibility, and also applied to indirectly determine the concentration of Fe3+ in aqueous solution.
本文成功合成了二三叉胺
钙[4]炔 L1,并将其用作聚
氯乙烯(P
VC)膜电极的离子载体。化合物 L1 被用于演示阴离子传感的新概念,即制备一种异构聚
氯乙烯膜,在
金属效应物存在的情况下,该膜可以对某种阴离子做出选择性反应。含有化合物 L1 和作为离子添加剂的四(对
氯苯基)
硼酸钾(KTpClPB)的膜在测量 Cu2+ 的电位(
EMF)反应时显示出唐南排阻失效,并通过负
EMF 变化对共阴离子做出反应,而含有化合物
L2(一种
蒽基单三足胺
配体)的膜则对大多数
金属离子给出正电位。在 CuC
L2 中对含有 L1 和 75 mol% KTpClPB 的膜进行预处理后,膜对
硫氰酸盐显示出最高的选择性,其斜率接近 Nernstian,为 -59.6 mV decade-1,线性范围为 10-5 至 10-2 M,检测限为 4.4 × 10-6 M。