Bi-functional glucose Sensing-Transmission (Sens-Tra) sensor for IoT-based applications

In the era of the Internet of Things (IoT) Ecosystem, multi-functional components have the potential to meet the needs of the exponential rise in the number of sensors/devices. Hence, in the future, the feasible complexity of the systems in IoT could be maintained using multi-functional components. This research aims to lower the hardware complexity at the edge devices in IoT architecture by incorporating both the sensing and data transmission capabilities into a single device, thereby eliminating the necessity of an external transmission device. Here, a state-of-the-art technique is developed, where a real-time, label-free, contact-based bi-functional Sens-Tra (Sensing-Transmission) operates as a sensor for glucose detection in aqueous solution as well as wireless transmission. To materialize this, a Circular Interdigital Capacitor Sensor (CIDCS) fed by a coplanar waveguide transmission line is proposed. The sensor operates over the Wi-Fi network, integrating leading-edge wireless technology with contact-based glucose sensing. The Wi-Fi network is established through ESP8266 Wi-Fi modules, and the Received Signal Strength Indicator (RSSI) is utilized as the sensing parameter for glucose detection. In addition to the sensing purpose, the bi-functional sensor is demonstrated for IoT-based applications, where RSSI is wirelessly transmitted from Sens-Tra to the cloud server, ThingSpeak, through mobile data. The data from the cloud can be processed and utilized through any web/mobile application, providing desired flexibility to the system. The experimental findings exhibit the potential of the bi-functional CIDCS for sensing as well as data transmission.