▎ 摘　　要

NOVELTY - Magnetic graphene quenched fluorescence detection system is prepared by (a) using "one-pot method" to synthesize magnetic graphene by dispersing graphene oxide into deionized water under ultrasonic conditions, slowly dropping mixed solution of iron(III) chloride and iron(II) chloride into the graphene oxide, adding L-cysteine, and aqueous ammonia, performing ultrasonic dispersion, putting reaction solution in a water bath for static reaction, centrifuging to obtain magnetic graphene after the reaction is over, and pretreating magnetic graphene, (b) loading antibodies on surface of magnetic graphene, (c) synthesizing fluorescent probe Aspergillus flavus B1-fluorescein, and (d) using the antibody-coupled magnetic graphene as energy acceptor and fluorescent probe A.flavus B1-fluorescein as energy donor to construct a quenching fluorescence detection system. USE - The system is useful for detecting magnetic graphene quenched fluorescence (claimed). ADVANTAGE - The system detects magnetic graphene quenched fluorescence in a simple, rapid and accurate manner with high sensitivity. DETAILED DESCRIPTION - Magnetic graphene quenched fluorescence detection system is prepared by (a) using "one-pot method" to synthesize magnetic graphene by dispersing graphene oxide into deionized water under ultrasonic conditions, slowly dropping mixed solution of iron(III) chloride and iron(II) chloride into the graphene oxide, adding L-cysteine, and aqueous ammonia, performing ultrasonic dispersion, putting reaction solution in a water bath for static reaction, centrifuging to obtain magnetic graphene after the reaction is over, and pretreating magnetic graphene, (b) loading antibodies on surface of magnetic graphene by adding morpholine ethanesulfonic acid buffer solution (MES) to pretreated magnetic graphene, stirring evenly at room temperature, adding Aspergillus flavus M1 antibody, stirring the reaction, adding bovine serum albumin (BSA) solution and blocking it, performing separation, washing it, and performing resuspension in phosphate buffer solution, and obtaining antibody-coupled magnetic graphene, (c) synthesizing fluorescent probe A.flavus B1-fluorescein by (i) weighing A.flavus B1 (AFB1), adding oxycarboxymethyl hydroxylamine hemihydrochloride (CMO), dissolving it in pyridine solution, heating and stirring to react to obtain AFB1-CMO, (ii) taking ethylenediamine and fluorescein isothiocyanate (FITC) respectively, adding methanol, dripping triethylamine, and stirring to dissolve, slowly dripping fluorescein isothiocyanate (FITC) solution into ethylenediamine solution, stirring reaction, washing precipitate, centrifuging it, and drying it in dark to obtain EDF, (iii) dissolving AFB1-CMO, dichloroethane (EDC) and N-hydroxysuccinimide (NHS) in dimethyl sulfoxide (DMF), stirring and reacting at room temperature for overnight, centrifuging to remove the precipitate and taking the supernatant to obtain the activated hapten solution, and (iv) dissolving EDF in DMF, add it to activated hapten solution, and stirring reaction mixture at room temperature, purifying by thin-layer chromatography, taking supernatant, which is fluorescent probe A.flavus B1-fluorescein, and (d) using the antibody-coupled magnetic graphene as energy acceptor and fluorescent probe A.flavus B1-fluorescein as energy donor to construct a quenching fluorescence detection system. An INDEPENDENT CLAIM is included for use of system for magnetic graphene quenched fluorescence detection, which is performed by adding sample to be tested to the magnetic graphene quenched fluorescence detection system, directly incubating it, subjecting to magnetic separation under UV light, displaying fluorescence signals visible to naked eye for qualitative detection or fluorescence spectrophotometer to measure fluorescence value, and performing quantitative detection according to standard curve.