▎ 摘　　要

NOVELTY - Preparation of functionalized graphene oxide-carbon nitride-silver bromide nanocomposite involves adding urea to graphene oxide dispersion solution, stirring at 80 degrees C for 3 hours and at 70 degrees C 6-12 hours, calcining at 550 degrees C for 2.5 hours, obtaining graphene oxide-carbon nitride composite, performing carboxylation treatment, dispersing in concentrated nitric acid solution, reacting, cooling, performing centrifugal washing to obtain carboxylated graphene oxide-carbon nitride composite, ultrasonically dispersing the carboxylated composite in water, adding silver nitrate solution, stirring, adding sodium bromide solution, mixing for 2 hours, centrifuging, washing, drying, ultrasonically dispersing the resultant graphene oxide-carbon nitride-silver bromide nanocomposite in water, adding N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride and sodium N-hydroxysuccinimide sulfonate, stirring, adding prostate antibody, slowly shaking at 4 degrees C for 6-12 hours, and centrifuging. USE - Preparation of functionalized graphene oxide-carbon nitride-silver bromide nanocomposite used in construction of immune complex for detecting of prostate antigen (all claimed) by colorimetric immunoassay method. DETAILED DESCRIPTION - Preparation of functionalized graphene oxide-carbon nitride-silver bromide nanocomposite involves adding urea to graphene oxide dispersion solution, stirring at 80 degrees C for 3 hours and at 70 degrees C 6-12 hours, calcining at 550 degrees C for 2.5 hours, obtaining graphene oxide-carbon nitride composite, performing carboxylation treatment, dispersing in concentrated nitric acid solution, reacting at 125 degrees C for 24 hours, cooling the resultant reaction mixture to room temperature, performing centrifugal washing to obtain carboxylated graphene oxide-carbon nitride composite, ultrasonically dispersing the carboxylated composite in water, adding silver nitrate solution, stirring in darkness for 1 hour, adding sodium bromide solution, mixing for 2 hours, centrifuging, washing, drying, ultrasonically dispersing the resultant graphene oxide-carbon nitride-silver bromide nanocomposite in water, adding N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride and sodium N-hydroxysuccinimide sulfonate, stirring at room temperature for 30 minutes, adding prostate antibody, slowly shaking at 4 degrees C for 6-12 hours, and centrifuging. An INDEPENDENT CLAIM is included for method for constructing immune complex, which involves heat preserving 5 mg/ml magnetic beads with 500-750 mu L prostate antibody at room temperature for 6-12 hours, washing, heat preserving different concentrations of prostate antigen for 30 minutes, then heat preserving 500-750 mu L nanocomposite solution for 30 minutes and washing.