一种用于液栅石墨烯场效应晶体管生化传感器中的差分型检测系统

Differential Detection System for Liquid Gate_Graphene Field Effect Transistor Biochemical Sensor

摘要: 基于微控制器的传感器检测系统具有多通道输出与输入、良好的人机交互性、可现场检测等优点，能够最大限度提升传感器的应用空间，因此成为传感器检测系统的主要发展方向之一。本文研制了基于STM32的差分型检测系统，可实现激励电压控制、量程选择、信号差分采集、数据实时显示与存储等功能。以pH敏感型液栅石墨烯场效应晶体管生化传感器为例，对检测结果进行线性拟合，拟合直线的斜率为−1.8，即被测溶液pH每变化1，该检测系统输出电流变化1.8 μA，线性相关系数R2 = 0.94。实验结果表明，该检测系统能够有效检测溶液pH，验证了系统的可行性。

Abstract: The sensor detection systems based on the micro-controller have the advantages of multi-channel output and input, friendly human-machine interaction and field detection. They can expand the application space of the sensor to the maximum. Thus, they have become one of the main development direction of the sensor detection systems. In this work, a differential detection system based on STM32 is developed, which can realize the control of driving voltage, selection of range measure, acquisition of signal differential detection, real-time data display and storage. We take the pH sensitive liquid gate_graphene field effect transistor biochemical sensor as an example to verify the feasibility of the system. The results of differential detection were linearly fitted, with an slope of −1.8 and a linear correlation coefficient of R2 = 0.94. The pH of solution change of 1 can induce 1.8 μA in the output current of detection system. The experimental results show that the detection system is able to effectively detect the pH of solution.