School of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, People's Republic of China.
Anal Chem. 2013 Jul 2;85(13):6477-84. doi: 10.1021/ac401028a. Epub 2013 Jun 21.
A novel, simple, portable, and low-cost method for diagnosis of hyperkalemia by using K(+)-recognizable poly(N-isopropylacrylamide-co-benzo-15-crown-5-acrylamide) [poly(NIPAM-co-B15C5Am)] linear copolymer as indicator is presented in this work. The pendent 15-crown-5 units in the linear copolymers can selectively and specifically recognize K(+) to form stable 2:1 "sandwich" host-guest complexes, which cause the copolymer chains to change from the hydrophilic state to the hydrophobic state isothermally, whereas other tested metal ions (e.g., Li(+), Na(+), Cs(+), Mg(2+), Ca(2+), Sr(2+), Ba(2+), Cu(2+), Fe(3+), Pb(2+), Cd(2+), Cr(3+)) cannot be recognized. With increasing the 15-crown-5 content or the K(+) concentration, the poly(NIPAM-co-B15C5Am) linear copolymers exhibit higher sensitivity to K(+). The hyperkalemia can be simply diagnosed by observing the K(+)-induced optical transmittance change of human blood samples with poly(NIPAM-co-B15C5Am) linear copolymer as an indicator. Normal blood samples with low potassium level containing the poly(NIPAM-co-B15C5Am) linear copolymer are almost transparent since the copolymer is hydrophilic and soluble at the operating temperature. However, severe hyperkalemia samples with high potassium level become completely cloudy since the copolymer is hydrophobic and insoluble at this temperature. The presented diagnosis method with poly(NIPAM-co-B15C5Am) linear copolymer as indicator is quite simple and low-cost, and it would bring a new candidate material to design simple and portable tools for diagnosis of hyperkalemia in the general population. Moreover, the results in this work provide valuable guidance for building novel poly(NIPAM-co-B15C5Am)-based artificial K(+)-recognizable "smart" or "intelligent" systems in various application fields.
本文提出了一种新颖、简单、便携且低成本的用于诊断高钾血症的方法，该方法使用 K(+)-识别性聚（N-异丙基丙烯酰胺-co-苯并-15-冠-5-丙烯酰胺）[poly（NIPAM-co-B15C5Am）]线性共聚物作为指示剂。线性共聚物中的苯并-15-冠-5 单元可以选择性和特异性地识别 K(+)以形成稳定的 2:1“三明治”主客体配合物，这导致共聚物链在恒温下从亲水状态转变为疏水状态，而其他测试的金属离子（例如，Li(+)、Na(+)、Cs(+)、Mg(2+)、Ca(2+)、Sr(2+)、Ba(2+)、Cu(2+)、Fe(3+)、Pb(2+)、Cd(2+)、Cr(3+)）不能被识别。随着 15-冠-5 含量或 K(+)浓度的增加，聚（NIPAM-co-B15C5Am）线性共聚物对 K(+)表现出更高的灵敏度。通过观察聚（NIPAM-co-B15C5Am）线性共聚物作为指示剂的人血样中 K(+)诱导的光透射率变化，可简单诊断高钾血症。含有聚（NIPAM-co-B15C5Am）线性共聚物的低钾水平正常血液样本几乎是透明的，因为共聚物在操作温度下亲水且可溶。然而，高钾水平的严重高钾血症样本由于共聚物在此温度下疏水且不溶而变得完全混浊。该方法使用聚（NIPAM-co-B15C5Am）线性共聚物作为指示剂非常简单且成本低廉，它将为设计用于普通人群高钾血症的简单便携工具提供新的候选材料。此外，本文的结果为构建新型基于聚（NIPAM-co-B15C5Am）的人工 K(+)-识别“智能”或“智能”系统提供了有价值的指导，可应用于各个领域。
