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

许多医学状况可以通过分析体液中循环的化学化合物来检测或诊断。一些与疾病有最具体联系的化合物是蛋白质。为了快速、轻松地检测蛋白质，需要电子传感器在与蛋白质接触时发出信号。提高传感器信号指示特定蛋白质存在的确定性的一种方法是去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。该项目将研究一种新的电路，由新的生物衍生电子材料构成，旨在消除这些不必要的信号。如果电路的一部分对干扰蛋白质产生反应，另一部分就会抵消信号。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的反应机制。其他活动将吸引和培训学生在多个层次，高中到大学，在材料，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。将通过参加约翰霍普金斯大学夏季“探索工程创新”和“生物医学工程创新”课程，招募代表性不足的少数民族学生参与该项目。本课程将开发一个示范和建模活动。对于疾病生物标志物的快速，灵敏和稳定的传感器有持续的需求。电子生物传感器通过局部电子参数（例如界面电位和复阻抗）的变化向受体发出生物标记物络合的信号。这些参数变化的起源包括离子重新分布，官能团重新取向，和受体的极化率的变化，并通过场效应晶体管（FET）报告。然而，FET基线不稳定性仍然是敏感和可靠的生物标志物检测的障碍。该项目探索了一种前所未有的“双串联栅极”有机电化学晶体管（DS-OECT），该晶体管基本上消除了更大信号/漂移比的基线不稳定性，从而将不稳定性分配给表面电位和阻抗波动。以相反极性连接的一对设备接口减少响应漂移，增加正确识别分析物的概率。目标包括材料合成，器件制造，计算机建模和生物流体分析。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

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.