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新型的固有导电聚合物薄膜，用于选择性检测无机阴离子，重点是磷酸盐和膦酸盐相关物种。磷酸根和膦酸根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。这些阴离子存在于肥料和药物中，传感器的目标是水环境和低浓度（10 - 6 mol/l），传感器材料能够通过同时改变光学（颜色/发射）和电学性质对分析物的存在进行反应。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，该聚合物材料具有整合到聚合物的π共轭主链中的阴离子选择性受体。在PI以前的研究中积累的关键知识将用于制备具有合适受体的单体和电聚合噻吩衍生物。这些传感器单体将电化学聚合在透明电极表面。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传感过程的准确性，增强特异性，并使这些材料能够在多阴离子环境中进行阴离子传感。在多阴离子环境中，通过使用带有不同受体的多个沉积材料的可单独寻址的透明微电极将实现可靠的阴离子传感，或者，通过两个或多个带有不同受体单元的传感器单体的共聚可以实现类似的效果。这些传感器涂层电极将用于构建传感器设备，并将在多分析物环境中进行测试。能够在低浓度下在极性/水溶液中感测阴离子底物的聚合物材料是罕见的。因此，需要努力将成功的分子传感器实现到聚合物材料中，这可以允许开发具有改进性能的鲁棒/稳定的材料。在这方面，特别重要的是通过两种独立的信号转导模式的并行实现来提高感测过程的可靠性和准确性的想法。这可以允许可靠地感测否则难以感测的阴离子底物。通过同时改变两个变量来检测阴离子的方法可以检测多种阴离子分析物。这一点尤其重要，因为尽管有很大的需求，但迄今为止还没有成功制备出既能提供高选择性又能进行多分析物传感的材料和器件。就更广泛的影响而言，本PI希望强调，拟议的研究将通过研究新型传感器材料来促进常识的发展。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，主要是医学和医学，例如，允许精确监测药物代谢，从而刺激新的药物代谢测定的发展。开发和研究这种新型的具有双模式信号转导的导电聚合物用于感测阴离子多分析物代表了一种新兴的和深远的研究和技术领域。该PI的团队还将通过出版物和积极参与科学会议，积极参与侧重于阴离子传感各个方面的跨学科讨论。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.