Sensor ToolKit (STK): Compact Multiplexing Potentiostat for Point-of-Care Applications

Embedded potentiostats have enabled the possibility of implementing electrochemical applications in a wide range of areas, from industry to healthcare. However, the optimization for either small size, low-cost devices, or sensor interfacing in existing platforms may lead to impractical outcomes. In this work, we propose Sensor ToolKit (STK), prototyped using off-the-shelf components and engineered to be a highly versatile, small, and low-cost platform of minimal complexity for the deployment of distributed IoT electrochemical sensors applications. The board implements an on-chip sequential input multiplexer that is especially suited for open-circuit potentiometry studies. The performance of the board was validated in potentiometric detection of potassium, hydrogen peroxide, glucose, and lactate, as well as self-current detection of hydrogen peroxide. Results show excellent analytical performance, comparable to that of benchtop instrumentation standards. The developed firmware and IoT framework enable the retrieval of sensor data wirelessly by a remote data server, which automates its real-time visualization using the Grafana web application, highlighting the potential of STK in distributed hyperconnected applications.嵌入式恒电位仪（Embedded potentiostats）已实现在从工业到医疗健康等广泛领域中开展电化学应用的可能。然而，现有平台中针对小型化、低成本设备或是传感器接口的优化方案，往往可能得出不切实际的应用结果。本研究中，我们提出传感器工具包（Sensor ToolKit，STK）：该套件采用现成商用组件完成原型开发，被设计为一款通用性强、体积小巧、成本低廉且复杂度极低的平台，可用于部署分布式物联网（IoT）电化学传感器应用。该电路板集成了片上顺序输入多路复用器，尤其适用于开路电位法研究。我们通过对钾离子、过氧化氢、葡萄糖及乳酸的电位检测，以及过氧化氢的自身电流检测，验证了该电路板的性能。实验结果表明，其分析性能优异，可与台式实验室仪器的行业标准性能相媲美。所开发的固件与物联网框架支持远程数据服务器无线获取传感器数据，并可通过Grafana网页应用实现数据实时可视化的自动化操作，凸显了STK在分布式超互联应用中的应用潜力。