title: Electrochemical determination of NADH based on MPECVD carbon nanosheets.
abstract: Characterization and application of carbon nanosheets (CNSs) grown by microwave plasma enhanced chemical vapor deposition (MPECVD) have been investigated for the electrochemical biosensor. The as-grown CNS films possess a porous structure with a large amount of graphene edges which most of them are less than 2 nm in thickness, as confirmed by scanning and transmission electron microscopes. "Surface-sensitive" probe, Fe(CN)(6)(3-/4-), exhibits that the original CNSs have faster electron transfer than glassy carbon electrode, owing to much more edge plane sites on the original CNS surface. "Oxygen-sensitive" probe, Fe(3+/2+) also confirmed that the oxygen species in the CNS film can improve its electrochemical activity. The modified electrode by MPECVD CNS films has been used to detect NADH for the first time. The CNSs with many graphene edges efficiently catalyse the oxidation of NADH at 0.336 V. The biosensor linearly responds to NADH in the range of 0-500 μM (R=0.99665), the sensitivity of the electrode is 85.8 mA M(-1) or 715 mA M(-1) cm(-2), and the detection limit of NADH is about 0.44 μM (S/N=3). The biosensor also displays excellent stability for NADH detection and good selectivity in the interference from ascorbic acid.
authors.affiliation: Institute for Sustainability Research and Education, Hosei University, 2-17-1, Fujimi, Tokyo 102-8160, Japan. wangzhipeng11@gmail.com
authors.forename: Zhipeng
authors.initials: Z
authors.lastname: Wang
authors.forename: Mao
authors.initials: M
authors.lastname: Shoji
authors.forename: Hironori
authors.initials: H
authors.lastname: Ogata
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D004563:Electrochemistry / Q000379:methods*; D008872:Microwaves; D009243:NAD / Q000032:analysis* / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry*; D010084:Oxidation-Reduction; D058626:Plasma Gases / Q000737:chemistry*; D014835:Volatilization
chemical_list: D058626:Plasma Gases; D009243:NAD; D002244:Carbon