Electrolyte-gated field Effect Transistors Based on Cu Interdigitated Electrode for H2O2 and Glucose Sensing

A copper interdigitated electrode was patterned on a piece of printed circuit board. A layer of CNRG-CS composite prepared using graphitic carbon nitride, reduced graphene oxide and chitosan was immobilized on Cu interdigitated electrode as semiconductive channel. Then, the prepared CNRG-CS modified Cu interdigitated electrode was positioned into a home-made chamber to assemble an electrolyte-gated field effect transistor (EGFET)-based sensor for the non-enzymatic detection of H 2 O 2 . Also, glucose oxidase (GOx) was immobilized on CNRG-CS modified Cu interdigitated electrode to prepare CNRG-CS/GOx modified Cu interdigitated electrode and to assemble an EGFET-based biosensor for the enzymatic detection of glucose. Two linear dynamic ranges of 0.16 − 8.0 μ M and 8.0 − 160 μ M were obtained for H 2 O 2 detection. Also, two linear dynamic ranges of 0.15 − 3.5 μ M and 3.5 − 80 μ M were obtained for glucose detection. The detection limits (S/N = 3) for H 2 O 2 and glucose were 0.12 and 0.14 μ M, respectively. The relative standard deviations for repetitive measurements (n = 3) of H 2 O 2 (3.0 μ M) and glucose (3.0 μ M) were 1.8 and 2.5%, respectively.