Preparation Of Graphene/Glassy Carbon Electrode For Electrochemical Sensors

Using gold nanoparticles as a catalyst,graphene was grown vertically on a glassy carbon substrate by chemical vapor deposition to prepare a new type of carbon electrode,a graphene / glassy carbon electrode.By analyzing the morphology,microstructure and composition changes,the quality and vertical controllable growth mechanism of graphene were studied.The carbon electrode is made of single-layer and multi-layer graphene covered glassy carbon,and has high electrical performance,small charge-transfer resistance at the electrode/electrolyte interface and large electrochemically active area.The carbon electrode can recognize a variety of electroactive biomolecules and inorganic ions,and has been proven to respond to up to 10 species.The DNA bases are G,A,T,and C,all of which are nitrogen-containing organic compounds.All four bases have the same element type and similar molecular structures.The electrocatalytic active sties of upright Gr sheets are composed of atomic defects such as catalyst atoms,edge point defects,and surface dislocations.In this paper,the electrochemical response of the carbon electrode to the four DNA bases of guanine(G),adenine(A),thymine(T)and cytosine(C)was specifically studied.The carbon electrode can recognize four DNA bases in a neutral electrolyte environment.The peak potential differences of A and G,T and A,C and T are 164,216,and 184 m V,respectively.The detection limits of G,A,T,and C are 0.3,0.4,6.5,and 4.5 μM,respectively.This carbon electrode has a strong bond between graphene and glassy carbon,without additional modification of sensitive materials.It can replace commercial glassy carbon,gold and carbon paste electrodes,and is more suitable for exploring new electrochemical sensors with high functionality and sensitivity.