Dual Series Gate Configuration, Materials Design, and Mechanistic Modeling for Drift-Stabilized, Highly Sensitive Organic Electrochemical Transistor Biosensors

许多疾病可以通过分析体液中循环的化学物质来检测或诊断。一些与疾病有最特殊联系的化合物是蛋白质。为了自信地快速、轻松地检测蛋白质，需要电子传感器在它们与蛋白质接触时发出信号。提高传感器信号表明特定蛋白质存在的确定性的一种方法是删除来自被分析液体中其他化合物的信号，如盐、脂肪或非目标蛋白质。这个项目将研究一种新的电路，用新的生物衍生电子材料建造，旨在消除这些不想要的信号。如果电路的一个部分对干扰蛋白质有反应，另一个部分就会抵消信号。该提案的活动包括为电路制造新的电子材料，并设计计算机模型来教授材料在使用时做出反应的机制。其他活动将吸引和培训从高中到大学的多个层次的学生，学习材料、电子、计算机和分析技术。研究生将获得高度多学科的培训，包括聚合物合成、表面电子学、器件技术和理论建模。来自少数族裔人口的学生将通过参加约翰·霍普金斯大学的暑期“探索工程创新”和“生物医学工程创新”课程来参与这一项目。将为本课程开发演示和建模练习。对于疾病生物标记物的快速、灵敏和稳定的传感器的需求持续存在。电子生物传感器通过改变局部电子参数，如界面电位和复阻抗，向受体发出生物标志物络合的信号。这些参数变化的起源包括离子重分布、功能基团重定向和受体极化率的变化，并通过场效应晶体管(FET)报告。然而，FET基线的不稳定性仍然是敏感和可靠的生物标志物检测的障碍。该项目探索了一种史无前例的“双串联栅极”有机电化学晶体管(DS-OECT)，该晶体管可大幅消除基线不稳定性，从而获得更大的信号/漂移比，从而能够将不稳定性分配给表面电位和阻抗波动。一对以相反极性连接的设备接口减少了响应漂移，增加了正确识别分析物的可能性。目标包括材料合成、器件制造、计算机建模和生物流体分析。关于设备响应机制的各种假设将被测试。这一奖项反映了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。

Many medical conditions can be detected or diagnosed by analyzing chemical compounds circulating in bodily fluids. Some of the compounds with the most specific connection to diseases are proteins. To confidently detect proteins quickly and easily, electronic sensors that signal when they are in contact with the proteins are needed. One way to improve the certainty that a sensor signal is indicating the presence of a particular protein is to remove signals that come from other compounds in the liquids being analyzed, like salt, fats, or non-target proteins. This project will investigate a new circuit, constructed with new biologically-derived electronic materials, designed to remove these unwanted signals. If one part of a circuit responds to an interfering protein, another part cancels the signal out. The activities of the proposal include making new electronic materials for the circuits and devising computer models that teach the mechanism by which the materials would respond when used. Other activities will attract and train students at multiple levels, high school through college, in materials, electronic, computer, and analytical technologies. Graduate students will gain highly multidisciplinary training, including polymer synthesis, surface electronics, device technology, and theoretical modeling. Students from underrepresented minority populations will be recruited to work on this project through outreach to the summer “Explore Engineering Innovation” and “Biomedical Engineering Innovation” courses at Johns Hopkins University. A demonstration and modeling activity for this course will be developed.There is an ongoing need for fast, sensitive, and stable sensors for disease biomarkers. Electronic biosensors signal biomarker complexation to receptors via changes in local electronic parameters such as interfacial potential and complex impedance. The origins of these parameter changes include ionic redistributions, functional group reorientation, and changes in the polarizability of receptors and are reported via field-effect transistors (FETs). However, FET baseline instability remains a barrier to sensitive and reliable biomarker detection. This project explores an unprecedented “dual-series gate” organic electrochemical transistor (DS-OECT) that substantially cancels baseline instability for greater signal/drift ratios, enabling assignment of instability to surface potential and impedance fluctuations. A pair of device interfaces connected in opposite polarities decrease response drift, increasing the probability of correct analyte identification. The objectives include material synthesis, device fabrication, computer modeling, and biological fluid analysis. Various hypotheses about the device response mechanisms will be tested.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.