Multianalyte Fluorescence Sensing of Phosphates

在这个由化学系化学结构、动力学和机理B项目资助的项目中，鲍林格林州立大学的Pavel Anzenbacher教授试图了解哪些分子特征支配着与磷酸盐相关的阴离子的识别和传感以及它们在水中的同时检测。磷酸盐相关阴离子在生物、工业和农业中具有重要的意义，但由于人工受体和传感器对水中阴离子的结合和传感效率低下，在水环境中对它们的分析仍然具有挑战性。目前的大多数方法都集中在对纯形式的磷酸盐的传感，而不是对其他竞争的磷酸盐类型的阴离子的传感。该项目致力于开发新型的超分子阴离子传感器，在磷酸盐类型的阴离子存在时显示荧光放大。这些新型传感器旨在解决在密切相关的阴离子混合物中识别和定量具有环境和/或生物意义的磷酸阴离子的长期挑战。建议的传感器由两个组件组成：磷酸盐受体和一种在磷酸盐存在下改变荧光的荧光染料。这两个部分以这样的方式连接，使得能够结合一系列磷酸阴离子，同时产生不同的荧光输出信号。有关磷酸盐阴离子传感的信息可能有助于开发新的廉价且广泛适用的磷酸盐和磷酸盐传感器。该项目有可能促进所需的知识，例如，开发更有效的环境传感平台或基于传感的生物技术，如实时定量聚合酶链式反应(QPCR)。这项研究为有机化学和光化学以及超分子化学的多学科教育提供了机会。环境传感方面和传感器在聚合酶链式反应(PCR)中的应用将为学生提供多方面的教育，并鼓励跨学科思维。本科生将在本科生研究和奖学金中心(CURS)计划的活动框架内由PI进行指导。CURS旨在通过积极参与研究来加强本科教育。PI还在家长参与儿童培养对科学的好奇心(野餐)计划中担任导师，该计划旨在让高中生接触化学研究并激发他们对科学的兴趣。阴离子在生物、工业和农业中的影响是广泛的，需要为这些物种开发新的和实用的传感概念。不幸的是，人工受体和传感器对水中阴离子的结合和传感效率低下。这项建议旨在增加对分子特征的理解，这些特征支配着与磷酸盐相关的阴离子的识别和传感以及它们在水中的同时检测。目前的大多数研究都描述了对纯形式的磷酸盐的传感，而没有其他竞争的磷酸盐类型的阴离子。该项目旨在解决一个长期存在的问题：确定和量化在密切相关的阴离子混合物中具有环境和/或生物意义的磷酸盐阴离子的特性和数量。因此，本项目的目标是开发基于受体-染料系综的交叉反应超分子传感器来检测磷酸类型的阴离子。提出的传感器由两部分组成：(I)双功能受体，包括金属结合部位，如二吡唑胺-锌(II)、钴(II)等，以及通过可变长度间隔连接的芳基硼酸；(Ii)能够与受体的两个部分结合的荧光染料。其工作原理如下：受体的金属络合物与荧光团配位，形成非荧光传感器系综。目标磷酸盐与受体的结合将荧光团从猝灭的金属位置喷射出来，然后与硼酸形成酯。荧光团与硼酸的络合物是明亮的荧光，导致荧光的急剧增加(开启)。记录的传感数据将使用模式识别方法(线性判别和主成分分析)进行处理。将使用线性回归算法进行定量分析。将使用人工神经网络和支持向量机算法进行进一步的研究，以提高传感器在检测极限、动态范围、线性等方面的性能。目标阴离子将是以磷为基础的富营养化试剂和除草剂磷酸盐，如草甘膦(也称为农达™)，以及在竞争电解质存在的情况下。这种新的传感方法还将用于生物磷酸盐(焦磷酸盐和核苷酸三磷酸盐)的传感，以应用于生物传感和相关技术，包括PCR。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

In this project, funded by the Chemical Structure, Dynamics & Mechanisms-B Program of the Chemistry Division, Professor Pavel Anzenbacher at Bowling Green State University seeks to understand which molecular features govern the recognition and sensing of phosphate-related anions and their simultaneous detection in water. Phosphate-related anions are of great importance in biology, industry, and agriculture but their analysis in aqueous environments remains challenging because of inefficient binding and sensing of anions in water by artificial receptors and sensors. Most current methods focus on sensing of phosphates in their pure form, without other competing phosphate-type anions. This project endeavors to develop new types of supramolecular anion sensors that show fluorescence amplification in the presence of phosphate-type anions. These new sensors are designed to address the long-standing challenge of identifying and quantitating phosphate anions of environmental and/or biological significance in mixtures of closely related anions. The proposed sensors are comprised of two components: phosphate receptors and a fluorescent dye that changes fluorescence in the presence of phosphate. These two moieties are connected in such a way that enables the binding of a range of phosphate anions while producing a different fluorescence output signal. The information on phosphate-type anion sensing will likely contribute to the development of new inexpensive and widely applicable sensors for phosphates and phosphonates. This project has the potential to advance knowledge required, for example, to develop more effective environmental sensing platforms or sensing-based biotechnologies such as the real-time quantitative polymerase chain reaction (qPCR). This research provides opportunities for multi-disciplinary education in organic chemistry and photochemistry, as well as supramolecular chemistry. The environmental sensing aspects and utility of the sensors in polymerase chain reaction (PCR) will provide for a multi-faceted education for students and encourage interdisciplinary thinking. Undergraduate students will be mentored by the PI within the framework of the activities of the Center for Undergraduate Research and Scholarship (CURS) program. CURS aims to enhance undergraduate education through active participation in research. The PI also acts as a mentor in the Parents Involvement with Children Nurturing Intellectual Curiosity in Science (PICNICS) program, designed to expose high school students to research in chemistry and stimulate their interest in science. The impact of anions in biology, industry, and agriculture is broad and requires the development of new and practical sensing concepts for such species. Unfortunately, the binding and sensing of anions in water by artificial receptors and sensors is inefficient. This proposal seeks to increase understanding of the molecular features that govern the recognition and sensing of phosphate-related anions and their simultaneous detection in water. Most current studies describe the sensing of phosphates in their pure form, without other competing phosphate-type anions. The project aims to address a long-standing problem: the determination of identity and quantification of phosphate anions of environmental and/or biological significance in the mixtures of closely related anions. Thus, the goal of this project is to develop cross-reactive supramolecular sensors based on receptor-dye ensembles to sense phosphate type anions. The proposed sensors are comprised of two components: (i) a bifunctional receptor comprising a metal binding site such as a dipicolylamine-Zn(II), Co(II), etc. and arylboronic acid connected via a variable-length spacer, and (ii) a fluorescent dye capable of binding both moieties of the receptor. The principle of operation is as follows: The metal complex of the receptors coordinates fluorophores to form a non-fluorescent sensor ensemble. Binding of target phosphates to the receptor ejects the fluorophore from the quenching metal site, which then forms an ester with boronic acid. The complex of the fluorophore with boronic acid is brightly fluorescent, resulting in a dramatic increase (turn-ON) of fluorescence. Recorded sensing data will be processed using pattern recognition methods (linear discriminant and principal component analysis). Quantitative analyses will be performed using linear regression algorithms. Further studies using artificial neural network (ANN) and support vector machines (SVM) algorithms will be performed to improve the performance of the sensors with respect to limits of detection, dynamic range, linearity, etc. The target anions will be phosphorus-based eutrophication agents and herbicide phosphonates such as glyphosate (also known as RoundUp™) in the presence of competing electrolytes. This new sensing method will also be utilized in sensing of biological phosphates (pyrophosphate and nucleotide triphosphates) for application in biosensing and related technologies including PCR.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.