4:20 PM - 4:35 PM
▼ [5p-A203-9] A study of protein adsorption behavior and protein-resistance strategy of carbon materials for electrochemical sensing application
Keywords:Electrochemistry, Carbon materials, Protein adsorption
With a wide potential window, chemical and electrochemical inertness, low capacitance, biocompatibility and low cost, carbon materials have been extensively used in electrochemical biosensors with highly promising applications. However, most of the devices reported in the literature for biosensors have not been tested in real biological samples, thus their practical value remains difficult to ascertain. Nonspecific adsorption of proteins may contaminate the electrode surface and have a severe impact on electrochemical signal response. In this way, numerous electrochemical biosensors are confined to laboratory stage. Therefore, biofouling arising from protein adsorption is a substantial challenge in biosensing systems, and antifouling sensing interfaces capable of resisting the nonspecific adsorption of proteins from biological complex samples are highly desirable.
To investigate the strategy of resisting protein adsorption towards carbon electrodes’ sensing interface in electrochemical application, at first it is necessary to have in-depth exploration of protein adsorption behaviors using electrochemical methods. Hence, the protein adsorption behaviors of various carbon materials have been investigated by Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV), including representative examples of glassy carbon (GC), graphene, boron-doped diamond (BDD). Compared with GC, graphene and oxygen terminated BDD (O-BDD), hydrogen terminated BDD (H-BDD) performed best in resisting protein adsorption. Interestingly, graphene modified electrode demonstrated quite different impedance response related to protein adsorption, due to its substantially higher sensitivity, providing more information about protein adsorption behaviors. Adsorption models of the interface between protein solutions and carbon electrode surfaces have been established.
What’s more, as a protein-resistance strategy towards carbon electrodes, a novel composite nanomaterial through the grafting of poly 2-methacryloyloxyethyl phosphorylcholine (PMPC) from graphene oxide (GO) nanosheets was prepared. The PMPC/rGO modified electrode can be easily achieved from PMPC/GO by electrochemical reduction, which remained highly conductive and at the same time demonstrated better antifouling performances even compared with hydrogen-terminated BDD, indicating great potential of this novel biomaterial in electrochemical sensing applications.
To investigate the strategy of resisting protein adsorption towards carbon electrodes’ sensing interface in electrochemical application, at first it is necessary to have in-depth exploration of protein adsorption behaviors using electrochemical methods. Hence, the protein adsorption behaviors of various carbon materials have been investigated by Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV), including representative examples of glassy carbon (GC), graphene, boron-doped diamond (BDD). Compared with GC, graphene and oxygen terminated BDD (O-BDD), hydrogen terminated BDD (H-BDD) performed best in resisting protein adsorption. Interestingly, graphene modified electrode demonstrated quite different impedance response related to protein adsorption, due to its substantially higher sensitivity, providing more information about protein adsorption behaviors. Adsorption models of the interface between protein solutions and carbon electrode surfaces have been established.
What’s more, as a protein-resistance strategy towards carbon electrodes, a novel composite nanomaterial through the grafting of poly 2-methacryloyloxyethyl phosphorylcholine (PMPC) from graphene oxide (GO) nanosheets was prepared. The PMPC/rGO modified electrode can be easily achieved from PMPC/GO by electrochemical reduction, which remained highly conductive and at the same time demonstrated better antifouling performances even compared with hydrogen-terminated BDD, indicating great potential of this novel biomaterial in electrochemical sensing applications.