▎ 摘　　要

NOVELTY - A graphene biosensor preparing method involves preparing graphene film by spin-coating graphene oxide aqueous solution to surface of cleaned and treated quartz substrate. The substrate is subjected to thermal annealing. The film on the quartz substrate is treated with an oxygen plasma to make the surface of the graphene film rich in oxygen-containing functional groups, followed by using 1-ethyl-3-(3-trimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide to activate the oxygen-containing functional groups on the surface of the film. Fixation of probe protein is carried out. USE - Method for preparing a graphene biosensor for detection of specific proteins and biomolecule. ADVANTAGE - The graphene biosensor can clearly see the effect of change of target protein concentration, and enables preparing the graphene biosensor with great application prospect. DETAILED DESCRIPTION - A graphene biosensor preparing method involves preparing graphene by spin-coating graphene oxide aqueous solution to surface of cleaned and treated quartz substrate. The substrate is placed in a tube furnace for thermal annealing in an atmosphere of argon and hydrogen at 800 degrees C to obtain a graphene film with uniform thickness of 8 nm. The graphene film on the quartz substrate is treated with an oxygen plasma (or graphene oxide solution) to make the surface of the graphene film rich in oxygen-containing functional groups, followed by using 1-ethyl-3-(3-trimethylaminopropyl)carbodiimide hydrochloride and N-hydroxysuccinimide to activate the oxygen-containing functional groups on the surface of the graphene film. Fixation of probe protein is carried out by adding the solution containing the probe protein to the surface of graphene and reacting at room temperature for a period of time, coupling a layer of probe protein on the surface of graphene and washing with phosphate buffer solution, immersing chip in bovine serum albumin solution, room temperature for a period of time, closing the chip surface residual carboxyl on the surface, and rinsing with phosphate buffer solution, and detecting optical sensor based on graphene polarization absorption effect in total internal reflection conditions.