title: Synergistic effect of pyrroloquinoline quinone and graphene nano-interface for facile fabrication of sensitive NADH biosensor.
abstract: A self-assembly composite of graphene-pyrroloquinoline quinone (PQQ) was fabricated and modified on glassy carbon electrode (GCE) for sensitive detection of nicotinamide adenine dinucleotide (NADH). Chitosan (CTS) was applied to disperse graphene to form a stable robust film on GCE. A synergistic effect between PQQ and graphene was observed during the electrocatalytic oxidation of NADH, with about 260mV reduction in the oxidation potential and 2.5-fold increase in the oxidation current compared with those on the bare GCE. The electrochemical sensors based on the modified electrodes allowed the detection of NADH with a good linear dependence from 0.32 to 220µM with a high sensitivity of 0.421µAµM-1cm-2and a low detection limit of 0.16µM (S/N=3). It could also eliminate the interference of electroactive substances like ascorbic acid (AA), uric acid, and dopamine and its derivatives. The outstanding performances of graphene-PQQ/CTS composite capable of improving the electrical conductivity and accelerating the electron transport suggested its promising applications for design of different graphene based composites used in electrochemical sensing and energy fields.
authors.affiliation: State Key Lab of Bioelectronics (Chien-Shiung Wu Laboratory), Southeast University, No. 2 Sipailou, Nanjing 210096, China.
authors.forename: Shanying
authors.initials: S
authors.lastname: Han
authors.affiliation: State Key Lab of Bioelectronics (Chien-Shiung Wu Laboratory), Southeast University, No. 2 Sipailou, Nanjing 210096, China.
authors.forename: Tianyu
authors.initials: T
authors.lastname: Du
authors.affiliation: State Key Lab of Bioelectronics (Chien-Shiung Wu Laboratory), Southeast University, No. 2 Sipailou, Nanjing 210096, China. Electronic address: sungi@seu.edu.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Jiang
authors.affiliation: State Key Lab of Bioelectronics (Chien-Shiung Wu Laboratory), Southeast University, No. 2 Sipailou, Nanjing 210096, China. Electronic address: xuewang@seu.edu.cn.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Wang
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D017097:Electric Impedance; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D008958:Models, Molecular; D009243:NAD / Q000097:blood*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D045542:PQQ Cofactor / Q000737:chemistry*
chemical_list: D009243:NAD; D045542:PQQ Cofactor; D006108:Graphite
keywords: Adsorption; Graphene; NADH; Oxidation; Pyrroloquinoline quinone