Immobilization Of Enzyme And Its Application In Electrochemical Sensors

As a rapid and efficient means of detection,electrochemical biosensors have a unique advantage in miniaturization.Detection of some usual physical signs by electrochemical sensors will be of very positive significance for both daily life and medical diagnosis.Enzyme has an excellent selectivity and efficient catalyzing process so that it was employed to fabricate senors.However,a carrier with good conductive,carrying capacity and electrochemical catalysis is necessary.As a new class of nanomaterials,graphene are widely used in electrochemical sensors because of its excellent electrical and chemical properties.Nevertheless,as a nature property of graphene,agglomeration would decrease its surface area and catalysis to limite the application in electrode materials.In the first part of this article,3D-structured PPy/graphene composite was synthesized by embedding polypyrrole(PPy)into graphene sheets via microwave assisted hydrothermal process under a low temperature and atmospheric pressure.The obtained results has shown good performance in non-enzyme dopamine(DA)detection,indicated good electrochemical catalytic activity and large surface.After immobilizing enzyme onto electrode,the fabricated sensor performed a good response and sensitivity.The second part of this article introduced a further work based on 3D-structured graphene,which etching graphene sheets by iron oxide to form a porous structure.Obtained porous graphene(PG)has outstanding catalytic activity and promising diffusion property because of its pore structure and rich edge sites.Both DA non-enzyme sensor and glucose enzymatic sensor has an admirable electrochemical response,and it can act as a good glucose sensor.