▎ 摘　　要

NOVELTY - Preparing flexible graphene self-assembled film involves selecting a polyimide film with a suitable size, and carrying out the first high-temperature carbonization on it. The non-carbon components are released in the form of gas, forming a disordered graphite structure as the temperature increases. The second high-temperature carbonization, molecular structure reformation are performed under high temperature conditions. The molecular structure changes to the layered graphite structure of the hexagonal plane. The polycondensation and denitrogenation are performed, the same large-area conjugated network structure as graphene is formed, that is, a flexible graphene self-assembled film is obtained. USE - Method for preparing flexible graphene self-assembled film for preparing a three-electrode biosensor for detecting dopamine (claimed) and glucose. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) a method for preparing a three-electrode biosensor, which involves pressing flexible graphene self-assembled film and the polyethylene terephthalate film together to form thin film, engraving film into three electrodes by laser engraving, corresponding to the working electrode, the counter electrode and the reference electrode, connecting one end of each electrode to the copper wire through conductive silver glue to obtain a three-electrode biosensor; and (2) use of three-electrode biosensor is claimed for detecting dopamine, where impurities on the surface of the electrode are washed and dried for direct detection of dopamine.