▎ 摘　　要

NOVELTY - Preparation of magnetic graphene oxide immobilized enzyme comprises taking graphene oxide (GO), adding 30-50% ethanol solution, performing ultrasonic dispersion for 0.5 hour, adding ferrous salt and iron salt, mixing for 30 minutes, reacting at 50 degrees C to reflux temperature for 1-2 hours, adjusting pH using ammonia to 11, mixing for 1-2 hours, performing magnetic separation, washing, drying graphene oxide/iron oxide (GO/Fe3O4) composite magnetic material, placing GO/Fe3O4 composite magnetic material and papain in phosphate buffer solution, placing in ultrasound for 30-45 minutes, performing magnetic separation, washing and drying magnetic graphene oxide immobilized enzyme. USE - Method of preparing magnetic graphene oxide immobilized enzyme used for corn starch extraction (claimed). ADVANTAGE - The method has simple process steps and high corn starch yield, can recycle magnetic graphene oxide immobilized enzyme 10 times and does not change rate and product quality.