Size-Selective Electrochemical Sensing via Metal-Organic Supercontainers

非技术摘要：离子的电化学传感在临床分析、环境监测和工业过程控制等领域发挥着重要作用。电化学传感器的一个特别重要的子类是离子选择电极(ISE)，它通过电信号检测目标离子。尽管各种有机分子已被用作离子载体(称为离子载体)以提高离子传感的选择性，但由于有机离子载体的化学限制，这些基于离子载体的离子载体的应用范围仍然受到限制。该项目由南达科他大学的王振强博士和秘鲁州立学院的内森·内泽博士领导，通过将一系列复杂的宿主分子作为一类新的离子载体整合到ISES中来应对这一挑战。这些主体表现出高度独特和可调的化学结构，使得实现尺寸选择性和预定的离子传感是可行的。这一新方法不仅显著扩展了ISES的范围，而且有可能改变基于离子载体的ISES的设计。该项目包含一个强大的教育和宣传部分，旨在促进在两个特定群体中开展科学、技术、工程和数学(STEM)教育，这两个群体的学生人数不足，即部落大学生和主要来自本科院校的学生。秘鲁州立学院是内布拉斯加州秘鲁的一个乡村小镇，该学院的本科生是在电化学传感领域进行尖端研究的团队的一员。该团队还计划在地区部落学院举办化学研讨会，并主办部落师生对在南达科塔大学进行夏季研究。技术摘要：在ISES中为分子离子传感的特定任务设计新的离子载体仍然是一个巨大的挑战。该项目中使用的新型离子载体代表了一类独特的合成受体，称为金属-有机超级容器(MOSCs)。MOSCs良好的化学和结构特征，包括组成的多功能性、结构的模块化和多孔结构，使其有别于其他合成的离子载体，为离子交换膜功能化和设计新的电化学传感应用提供了前所未有的机会。这项为期两年的项目集中于三个具体目标：1)将MOSCs整合到各种聚合物混合基质膜中；2)MOC整合ISES的基础研究；3)通过整合靶标特异性MOSCs来调节ISES的专一性。通过参与这项研究活动，研究生和本科生研究人员可以接触到从材料合成、电化学分析到器件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.