SENSORS: Multi-Anion Sensing by Conductive Polymers with Dual Mode of Signal Transduction

本提案的目的是开发和研究一种新型的、固有导电性的聚合物薄膜，这种薄膜将用于无机阴离子的选择性传感，重点是磷酸盐和磷酸盐相关的物种。磷酸盐和磷酸盐阴离子水平的检测和定量测量是药物测试和药理学（药代动力学）研究以及环境监测的重要要求。这些阴离子，发现在肥料和药物，是针对水环境和低浓度（10 -6 mol/l）。将开发能够通过同时改变光学（颜色/发射）和电学特性对分析物的存在作出反应的传感器材料。两种独立的信号转导模式的结合将提高传感过程的选择性和可靠性。这将通过制备新型聚噻吩基聚合物材料来实现，该材料将阴离子选择性受体整合到聚合物的π共轭主链中。在PI之前的研究中积累的关键知识将用于制备含有合适受体和电聚合噻吩衍生物的单体。这些传感器单体将在透明电极表面进行电化学聚合。这种涂有阴离子传感器材料的透明电极将用于制造光谱电化学电池，这将允许使用两种信号转导模式来研究阴离子结合：光学和电学性质的变化。双模式信号转导有望提高批发过程的准确性，增强特异性，并使这些材料能够在多阴离子环境中感知阴离子。在多阴离子环境中，可靠的阴离子传感将通过使用带有不同受体的多种沉积材料的可单独寻址的透明微电极来实现。或者，可以通过两个或多个具有不同受体单元的传感器单体的共聚来实现类似的效果。这些传感器涂层电极将用于制造传感器设备，并将在多种分析环境中进行测试。拟议研究的智力价值是多方面的。在低浓度极性/水溶液中能够感应阴离子底物的聚合物材料是罕见的。因此，努力将分子传感器成功地应用到聚合物材料中，这可能会使开发具有改进性能的坚固/稳定材料成为可能。在这方面特别重要的是通过同时实现两种独立的信号转导模式来提高传感过程的可靠性和准确性。这可能允许可靠地感应阴离子底物，否则难以感应。通过同时改变两个变量来检测阴离子的方法可以检测多个阴离子分析物。这一点尤其重要，因为尽管需求量很大，但到目前为止，还没有成功制备出既能提供高选择性又能允许多分析物传感的材料和设备。就更广泛的影响而言，该PI想强调，拟议的研究将通过研究新型传感器材料来促进一般知识的进步。所提出的多阴离子传感器将在各种各样的应用中非常有用，主要是医疗和环境，例如允许对药物代谢进行精确监测，从而刺激新型药物代谢测定的发展。开发和研究这种具有双信号转导模式的新型导电聚合物，用于感应阴离子多分析物，代表着对新兴和深远的研究和技术领域的冒险。该PI的团队还将积极参与跨学科讨论，重点关注阴离子传感的各个方面，通过出版和积极参与科学会议。最后但并非最不重要的是，更广泛的社会将受益于教育的进步，从而有助于合格劳动力的专业培训。

The objective of this proposal is the development and study of novel, inherently conductivepolymer thin films that will be used for selective sensing of inorganic anions with emphasis onphosphate- and phosphonate-related species. The detection and quantitative measurement of levels ofphosphate and phosphonate anions is an important requirement for drug testing and pharmacological(pharmacokinetic) studies as well as environmental monitoring. The sensing of these anions, found infertilizers and pharmaceuticals, is aimed at aqueous environment and low concentrations ( 10 -6 mol/l).Sensor materials capable of reacting to the presence of analyte by change of optical(color/emission) and electrical properties in a simultaneous regime will be developed. The combination oftwo independent modes of signal transduction will improve the selectivity and reliability of the sensingprocess. This will be accomplished by preparing novel polythiophene-based polymer materials withanion-selective receptors integrated into the pi-conjugated backbone of the polymer. The criticalknowledge amassed during the PI's previous studies will be used to prepare monomers bearing suitablereceptors and electropolymerizable thiophene derivatives. These sensor monomers will beelectrochemically polymerized on the surface of transparent electrodes. Such transparent electrodescoated with anion sensor material will be used to fabricate spectroelectrochemical cells, which will allowfor investigation of anion binding using two modes of signal transduction: changes in optical andelectrical properties. The two-mode signal transduction is expected to increase the accuracy of the wholesensing process, enhance specificity and make these materials capable of anion sensing in multi-anionenvironments. Reliable anion sensing in multi-anion environments will be achieved by using individuallyaddressable transparent microelectrodes with multiple deposited materials bearing different receptors.Alternatively, similar effect may be achieved by copolymerization of two or more sensor monomersbearing different receptor units. These sensor-coated electrodes will be used to build sensor devices andwill be tested in multi-analyte environments.The intellectual merit of the proposed research is diverse. Polymer materials capable of sensingof anionic substrates in polar/aqueous solutions at low concentrations are rare. Efforts towardimplementing successful molecular sensors into polymer materials, which may allow the development ofrobust/stable materials with improved performance, are therefore desirable. Particularly important in thisregard is the idea of improved reliability and accuracy of the sensing process by simultaneousimplementation of two independent modes of signal transduction. This may allow for reliable sensing ofanionic substrates that are otherwise difficult to sense. The approach of detecting the anion by change oftwo variables in a simultaneous regime may allow for sensing of multiple anionic analytes. This isparticularly important because, despite the great need, materials and devices that would provide both highselectivity and allow for multi-analyte sensing have not been successfully prepared so far.In terms of the broader impacts, this PI would like to emphasize that the proposed research willserve for the advancement of general knowledge by investigating novel sensor materials. The proposedmulti-anion sensors would be highly useful in a wide variety of applications, mostly medical andenvironmental, for example to allow for a precise monitoring of drug metabolization thus stimulate adevelopment of novel drug-metabolization assays. The development and investigation of such novel,conductive polymers with dual mode of signal transduction for sensing anionic multi-analytes representsa venture into an emerging and far reaching area of research and technology. This PI's team will also takeactive part in an interdisciplinary discussion focused on various aspects of anion sensing throughpublication and active participation in scientific meetings. Last but not least, the broader community willbenefit through the advancement of education thus contributing to professional training of qualifiedworkforce.