Fig. 6: PCB design and functional validation of the VCMGS system.
From: Vertical graphene-coated core-shell microneedle as miniatured sensor for in vivo glucose monitoring
a−c Structural schematic and optical images of the VCMGS system. The system comprised the VCMGS, an embedded circuit and a smartphone software interface. The hardware included four key modules: a microcontroller unit (MCU), Bluetooth Low Energy (BLE) module, analog front end (AFE), and the VCMGS. d Logic block diagram of the PCB circuit. e Performance evaluation of the PCB sensing circuit module, including the input-output current relationship for the glucose sensing module. f, g Comparative analysis of the detection performance between the PCB circuit and a commercial electrochemical workstation, along with corresponding normalized statistical results. h Customized application interface designed for integration with the PCB. i Photograph showing the application of the VCMGS on the forelimb of a live Bama miniature pig for continuous signal acquisition. j Time-dependent glucose concentration in subcutaneous tissue of the pig monitored by the VCMGS system. Green dots represented reference blood sampling values, and asterisks denoted calibration points. k Clarke error grid depicting the accuracy of subcutaneous glucose detection using the VCMGS system in vivo. Abbreviations: PWR, power management module; UART, Universal Asynchronous Receiver/Transmitter; SPI, Serial Peripheral Interface
