▎ 摘　　要

NOVELTY - Immobilizing enzyme by oxidation of graphene-metal ion comprises: (i) preparing crude enzyme solution; (ii) preparing pure enzyme; (iii) preparing graphene oxide solution; (iv) preparing graphene-metal ion coordination immobilization carrier; and (v) preparing immobilized enzyme by mixing of oxidized graphene-metal ion complex immobilized carrier suspension with enzyme solution with 0.1-10 mg/ml His-tag target enzyme, oscillating at 4-35 degrees C for 1-5 hours, centrifuging, washing, resuspending to obtain oxidized graphene-metal ion complex immobilized enzyme. USE - The method is useful for immobilizing enzyme by oxidation of graphene-metal ion (claimed). ADVANTAGE - The immobilizing method is simple with mild preparation condition and high immobilization rate. The immobilized enzyme has temperature stability, pH stability and high enzyme activity recovery rate. DETAILED DESCRIPTION - Immobilizing enzyme by oxidation of graphene-metal ion comprises: (i) preparing crude enzyme solution by inoculating the recombinant expression strain capable of expressing a target enzyme with His-tag and culturing, adding lactose inducer IPTG, culturing the obtained bacterial solution, harvesting the cells by centrifugation to obtain cell suspension, carrying out ultrasonic disruption, centrifuging, collecting supernatant containing His-tag target enzyme crude solution; (ii) preparing pure enzyme by purifying crude enzyme solution and desalting using nickel column to obtain target enzyme with His-tag; (iii) preparing graphene oxide solution by dissolving graphene oxide in pure water, carrying out ultrasonic dispersion to obtain 0.1-10 mg/ml dispersed graphene oxide, centrifuging, collecting the supernatant to obtain graphene oxide solution; (iv) preparing graphene-metal ion coordination immobilization carrier by selecting of metal ions which had no obvious inhibitory effect on free enzyme activity, adding 0.1-10 mM oxidized graphene solution and metal ions, coordinating in solution, oscillating at 4-35 degrees C for 1-5 hours to obtain the suspension of oxidized graphene-metal ion complex-immobilized carrier; and (v) preparing immobilized enzyme by mixing of oxidized graphene-metal ion complex immobilized carrier suspension with enzyme solution with 0.1-10 mg/ml His-tag target enzyme, oscillating at 4-35 degrees C for 1-5 hours, centrifuging, washing, resuspending to obtain oxidized graphene-metal ion complex immobilized enzyme. An INDEPENDENT CLAIM is also included for immobilized enzyme, prepared as mentioned above.