Carbon Nitride-Supported Copper Oxide for Non-Enzymatic Glucose Sensor: A Multi-Platform Approach Utilizing Electrochemical, Field Effect Transistor and Microcontroller-based IoT Systems

The new generation of glucose biosensors has attracted significant research interest due to its fast response, high stability, reproducibility, portability and low detection limit. In this work, various types of high-performance non-enzymatic glucose sensors are proposed, based on carbon nitride supported copper oxide nanoparticles (CNCO). The hybrid system was synthesized using a modified deposition-precipitation route where the copper oxide nanoparticles were dispersed on the carbon nitride matrix. The X-ray diffraction pattern revealed that the copper oxide nanoparticles exhibit a high degree of crystallinity with a monoclinic structure. The synthesized hybrid material was used as a catalyst for the electrochemical detection of glucose in the range of 0 to 15.6 mM, demonstrating a detection limit of 0.59 mM and a sensitivity of 0.53 mA.mM^-1.cm^-2. The CNCO based extended gate field effect transistor, at different glucose concentrations (1-9 mM), showed limit of detection and sensitivity values of 0.59 mM and 0.065 mA.mM^-1.cm^-2, respectively. A microcontroller-based glucose sensor was also implemented in this study that exhibited the sensitivity value of 1.46 mV/mM within the concentration range of 2-8 mM. The carbon nitride-supported copper oxide-based glucose sensors exhibit excellent reproducibility, sufficient stability and high selectivity, making them a promising candidate for real-life sensing applications.