Size-Selective Electrochemical Sensing via Metal-Organic Supercontainers

非技术摘要：离子的电化学传感在包括临床分析、环境监测和工业过程控制在内的各个领域中具有关键作用。电化学传感器的一个特别重要的子组是离子选择性电极（ISE），其通过电信号检测目标离子。尽管多种有机分子已在ISE中用作离子载体（称为“离子载体”）以提高离子感测中的选择性，但由于有机离子载体的化学限制，这些基于离子载体的ISE的应用范围仍然受到限制。由南达科他州大学的Zhenqiang Wang博士和秘鲁州立学院的Nathan Netzer博士领导的项目通过将复杂的宿主分子家族作为一类新的离子载体整合到ISE中来解决这一挑战。这些主机表现出高度独特和可调的化学结构，使其可行的实现尺寸选择性和预定的离子传感。这种新方法不仅大大扩展了ISE的范围，而且有可能改变基于离子载体的ISE的设计。该项目包含一个强有力的教育和推广部分，旨在促进科学，技术，工程和数学（STEM）教育在两个特定的群体中代表性不足的学生群体，即部落大学生和主要本科院校的学生（PUI）。秘鲁州立大学是内布拉斯加州秘鲁的一个小农村PUI，该校的本科生是电化学传感领域前沿研究团队的一员。 该小组还计划在区域部落学院举办化学研讨会，并在南达科他州大学举办部落师生对夏季研究。技术摘要：设计新的离子载体在离子选择电极的分子离子传感的特定任务继续提出重大挑战。在这个项目中使用的一类新的离子载体代表了一个独特的合成受体家族，称为金属有机超级容器（MOSC）。MOSC的有利的化学和结构特征，包括其组成的多功能性，结构模块性和多孔结构，将它们与其他合成离子载体区分开来，并为功能化ISE和设计新的电化学传感应用提供了前所未有的机会。这个为期两年的项目集中在三个具体目标：1）将MOSC纳入各种聚合物混合基质膜; 2）MOSC集成ISE的基础研究; 3）通过纳入靶向特异性MOSC来调整ISE的特异性。通过参与这项研究活动，研究生和本科生研究人员接触到从材料合成和电化学分析到设备制造的各种实验技术。

Non-technical Abstract:Electrochemical sensing of ions has a critical role in various fields including clinical analysis, environmental monitoring, and industrial process control. One particularly important subgroup of electrochemical sensors are ion-selective electrodes (ISEs), which detect target ions by electrical signals. Although a variety of organic molecules have been used in ISEs as ion-carriers (known as "ionophores") to improve the selectivity in ion sensing, the scope of applications for these ionophore-based ISEs remains restricted due to the chemical limitations of the organic ionophores. The project led by Dr. Zhenqiang Wang at the University of South Dakota and Dr. Nathan Netzer at Peru State College addresses this challenge by integrating into the ISEs a family of complex host molecules as a new class of ionophores. These hosts exhibit highly unique and tunable chemical structures, making it feasible to achieve size-selective and predetermined ion sensing. This new approach not only significantly expands the scope of ISEs, but has the potential to transform the design of ionophore-based ISEs. This project contains a strong educational and outreach component that aims to promote science, technology, engineering, and mathematics (STEM) education among two specific groups of underrepresented student populations, namely, tribal college students and students from primarily undergraduate institutions (PUIs). Undergraduates at Peru State College, a small rural PUI in Peru, Nebraska, are part of the team to perform cutting-edge research in the field of electrochemical sensing. The team also plans to conduct chemistry workshops at regional tribal colleges and host tribal student-faculty pairs to perform summer research at the University of South Dakota.Technical Abstract:Designing new ionophores in ISEs for the specific task of molecular ion sensing continues to present significant challenges. The new class of ionophores utilized in this project represents a unique family of synthetic receptors known as metal-organic supercontainers (MOSCs). The favorable chemical and structural characteristics of the MOSCs, including their compositional versatility, structural modularity, and multi-pore architecture distinguish them from other synthetic ionophores and provide unprecedented opportunities for functionalizing ISEs and engineering new electrochemical sensing applications. This two-year project focuses on three specific aims: 1) incorporation of MOSCs into various polymeric mixed-matrix membranes; 2) fundamental studies of MOSC integrated ISEs; 3) tuning the specificity of ISEs by incorporating target-specific MOSCs. By participating in this research activity, graduate students, and undergraduate researchers are exposed to a diverse set of experimental techniques ranging from materials synthesis and electrochemical analysis to device fabrication.