▎ 摘　　要

NOVELTY - An aptamer-modified magnetic graphene oxide composite material comprises thiol modified aptamer of magnetic graphene oxide composite covalently modified gold nanoparticle. USE - Aptamer-modified magnetic graphene oxide composite material. ADVANTAGE - The composite material has high efficiency, and high selectivity enrichment of target proteins. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method of preparing an aptamer-modified magnetic graphene oxide composite material comprising mixing 1 pts. wt. magnetic graphene oxide and 1-10 pts. wt. thiol modified aptamer, stirring, adding tris-hydrochloric acid buffer solution having a concentration of 1-500 mu M to adjust pH value to 7.2-8, reacting at room temperature for 1-48 hours, adding tris-hydrochloric acid buffer solution having a concentration of 1-500 mu M to adjust pH value to 7.2-8, adding stabilizer and polyethylene imine as reducing agent, stirring for 1-10 hours, adding water and chloroauric acid, mixing, water bath heating at 60-95 degrees C while stirring for 1-4 hours, washing with deionized water, subjecting to ultrasonic washing for 1-10 hours, adding (5-amino-1-carboxylpentyl) iminodiacetic acid and an alkali, subjecting to ring opening reaction, centrifuging, filtering, adding morpholine ethyl sulfonic acid to the filtrate, regulating pH value at 3-6, adding 1-ethyl-3-(3-dimethyl amine propyl)carbodiimide and N-hydroxyl succinimide as activate agent, stirring, adding ferroferric oxide, and subjecting to ultrasonic activation for 1-2 hours.