A Flexible Multi-Ion Detection System Based on Organic Electrochemical Transistors for Physiological Monitoring

The continuous and real-time monitoring of physiological indicators is essential for early disease detection, prevention, and clinical diagnosis. In response to the growing demand for precise physiological parameter assessment, this study presents a flexible, organic electrochemical transistor (OECT)-based multi-ion sensing system designed to monitor key electrolyte concentrations—sodium (Na+), potassium (K+), and calcium (Ca2+)—in human biofluids. The system features a highly adaptable sensor array with a detection range tailored to physiological conditions, ensuring high selectivity and stability in complex biological environments. Our sensor demonstrated a sensitivity exceeding 1 mA/decade. To enhance measurement accuracy and mitigate cross-interference among ions, we integrate advanced machine learning algorithms, which optimize signal processing and significantly improve the system’s reliability. Additionally, we have developed a fully integrated hardware–software platform comprising customized signal acquisition circuitry and dedicated data analysis software, specifically tailored for OECT-based sensing applications. This comprehensive framework not only refines real-time ion detection but also paves the way for the broader clinical translation of OECT technology. The proposed system holds great promise for real-time physiological monitoring and point-of-care diagnostics, offering a potential paradigm shift in non-invasive, on-demand health assessment.