▎ 摘　　要

NOVELTY - Preparation of immobilized alpha -amylase with graphene/titanium dioxide composite porous microsphere carrier involves preparing graphene oxide porous ball, adding into mixture of cyclohexane, anhydrous ethanol, oleic acid, tetrabutyl titanate and triethylamine, reacting mixture, filtering to obtain residue, reacting residue with crosslinking agent solution, treating with liquid reducing agent to obtain carrier, adding carrier into alpha -amylase solution, stirring mixture, ultrasonicating at 300 W for 1-4 hours, filtering mixture, washing residue with citric acid-sodium citrate buffer, and drying. USE - Method for preparing immobilized alpha -amylase with graphene/titanium dioxide composite porous microsphere carrier (claimed). ADVANTAGE - The immobilized alpha -amylase has good thermal stability, and less inactivation after repeated use. DETAILED DESCRIPTION - Preparation of immobilized alpha -amylase with graphene/titanium dioxide composite porous microsphere carrier comprises mixing graphene oxide and deionized water, ultrasonicating with stirring at 500 W for 1-5 hours to obtain graphene oxide solution, adding obtained solution dropwise to receiving liquid controlled by cryogenic freezing bath, freeze-drying mixture, and vacuum-drying at 100 degrees C to obtain graphene oxide porous ball; mixing cyclohexane and anhydrous ethanol, adding oleic acid with stirring, stirring mixture for 30 minutes, adding obtained solution dropwise to tetrabutyl titanate and triethylamine mixture, stirring mixture further for 30 minutes, adding obtained graphene oxide porous ball, transferring mixture to reaction kettle, reacting at 150-180 degrees C for 10-20 hours, cooling reaction mixture to room temperature, filtering, washing residue with deionized water and absolute ethanol, drying, adding solid into crosslinking agent solution, heating at 55-75 degrees C on water bath for 1-5 hours, and treating with liquid reducing agent to obtain graphene/titanium dioxide composite porous microspheres carrier; and preparing alpha -amylase solution, mixing solution with obtained carrier, stirring mixture for 1-2 hours, ultrasonicating at 300 W for 1-4 hours, filtering mixture, washing residue with citric acid-sodium citrate buffer, and drying.