Two-dimensional graphene and transition metal dichalcogenide field effect transistor biosensors for biomedical diagnostics and sensing applications

Two-dimensional (2D) materials are appealing choices for next-generation biosensors due to their atomic-scale thickness, high surface-to-volume ratio, and improved electrical properties. Among these, graphene and transition metal dichalcogenides (TMDCs) are attracting significant interest for field-effect transistor (FET)-based medical biosensing applications. This paper gives an extensive review of 2D FET biosensors based on graphene and TMDCs with a focus on their material properties, device configurations, operating principles, and biomedical applications. While TMDCs offer narrow band gaps, high on/off current ratios, and enhanced electrical stability, making them appropriate for low-power and dependable sensing, graphene offers remarkable carrier mobility and ambipolar transport, permitting great sensitivity. The sensitivity, operating voltage and real-time detection capacity of several FET configurations-such as back-gate, liquid-gate, dual-gate and extended-gate structures are methodically examined. Applications in point-of-care testing, health monitoring and illness detection are highlighted in this assessment of recent developments in scalable synthesis approaches and device integration. CMOS compatibility, environmental stability, material uniformity, and device variability are among the significant challenges that are also discussed. Finally, future directions are discussed, with an emphasis on smart sensing platforms, wearable and flexible biosensors, single-molecule detection, and sustainable 2D material technologies for next-generation biomedical applications.