Palacios Manuel A, Nishiyabu Ryuhei, Marquez Manuel, Anzenbacher Pavel
Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, Ohio 43403, USA.
J Am Chem Soc. 2007 Jun 20;129(24):7538-44. doi: 10.1021/ja0704784. Epub 2007 May 27.
Reliable sensing of structurally similar anions in water is a difficult problem, and analytical tests and sensor devices for reliable sensing of multiple anions are very rare. This study describes a method for fabrication of simple colorimetric array-based assays for aqueous anion solutions, including complex analytes encountered in real-life applications. On the fundamental level, this method shows how the discriminatory capacity of sensor arrays utilizing pattern recognition operating in multianalyte environments may be dramatically improved by employing two key features. The synergy between the sensor and hydrogel host resembles the cooperative effects of an apoenzyme and cofactor: the host hydrogel helps extract the target anions from the bulk analyte while stripping the solvate molecules off the anions. In addition, the supramolecular studies of the affinity and selectivity of the potential sensors for target analytes allow for constructing an array predesigned for a particular analyte. To illustrate both aspects, an eight-sensor array utilizing colorimetric sensor materials showing selectivity for fluoride and pyrophosphate while displaying significant cross-reactivity for other anions such as carboxylates, phosphate, or chloride was used to differentiate between 10 anions. The quantitative analyses were also performed to show that the eight-sensor array was found to operate across 4 orders of magnitude concentrations (0.20-360 ppm; 10 microM to 20 mM). The applicability of this approach was demonstrated by analyzing several toothpaste brands. The toothpastes are complex analytes comprising both known and unknown anions in various concentrations. The fluoride-selective yet cross-reactive array is shown to utilize the fluoride content as the main differentiating factor while using the remaining anionic components for further differentiation between toothpaste brands.
可靠地检测水中结构相似的阴离子是一个难题，用于可靠检测多种阴离子的分析测试和传感器设备非常罕见。本研究描述了一种用于制备基于比色阵列的水溶液阴离子检测方法，包括实际应用中遇到的复杂分析物。在基础层面上，该方法展示了通过采用两个关键特性，如何显著提高在多分析物环境中利用模式识别的传感器阵列的辨别能力。传感器与水凝胶主体之间的协同作用类似于脱辅基酶和辅因子的协同效应：主体水凝胶有助于从大量分析物中提取目标阴离子，同时去除阴离子上的溶剂化分子。此外，对潜在传感器与目标分析物的亲和力和选择性进行超分子研究，有助于构建针对特定分析物预先设计的阵列。为了说明这两个方面，使用了一种八传感器阵列，该阵列利用对比色传感器材料对氟化物和焦磷酸盐具有选择性，同时对其他阴离子（如羧酸盐、磷酸盐或氯化物）表现出显著的交叉反应性，以区分10种阴离子。还进行了定量分析，结果表明八传感器阵列在4个数量级的浓度范围内（0.20 - 360 ppm；10 microM至20 mM）均可运行。通过分析几个牙膏品牌证明了该方法的适用性。牙膏是复杂的分析物，包含各种浓度的已知和未知阴离子。结果表明，具有氟选择性但交叉反应性的阵列将氟化物含量作为主要区分因素，同时利用其余阴离子成分进一步区分不同品牌的牙膏。
