title: Electrochemical sensing and biosensing platform based on chemically reduced graphene oxide.
abstract: In this paper, the characterization and application of a chemically reduced graphene oxide modified glassy carbon (CR-GO/GC) electrode, a novel electrode system, for the preparation of electrochemical sensing and biosensing platform are proposed. Different kinds of important inorganic and organic electroactive compounds (i.e., probe molecule (potassium ferricyanide), free bases of DNA (guanine (G), adenine (A), thymine (T), and cytosine (C)), oxidase/dehydrogenase-related molecules (hydrogen peroxide (H2O2)/beta-nicotinamide adenine dinucleotide (NADH)), neurotransmitters (dopamine (DA)), and other biological molecules (ascorbic acid (AA), uric acid (UA), and acetaminophen (APAP)) were employed to study their electrochemical responses at the CR-GO/GC electrode, which shows more favorable electron transfer kinetics than graphite modified glassy carbon (graphite/GC) and glassy carbon (GC) electrodes. The greatly enhanced electrochemical reactivity of the four free bases of DNA at the CR-GO/GC electrode compared with that at graphite/GC and GC electrodes makes the CR-GO/GC electrode a better choice for the electrochemical biosensing of four DNA bases in both the single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) at physiological pH without a prehydrolysis step. This allows us to detect a single-nucleotide polymorphism (SNP) site for short oligomers with a particular sequence at the CR-GO/GC electrode without any hybridization or labeling processes in this work, suggesting the potential applications of CR-GO in the label-free electrochemical detection of DNA hybridization or DNA damage for further research. Based on the greatly enhanced electrochemical reactivity of H2O2 and NADH at the CR-GO/GC electrode, CR-GO/GC electrode-based bioelectrodes (in connection with glucose oxidase (GOD) and alcohol dehydrogenase (ADH)) show a better analytical performance for the detection of glucose and ethanol compared with graphite/GC- or GC-based bioelectrodes. By comparing the electrochemical performance of CR-GO with that of the conventional graphite and GC, we reveal that CR-GO with the nature of a single sheet showing favorable electrochemical activity should be a kind of more robust and advanced carbon electrode material which may hold great promise for electrochemical sensors and biosensors design.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhou
authors.forename: Yueming
authors.initials: Y
authors.lastname: Zhai
authors.forename: Shaojun
authors.initials: S
authors.lastname: Dong
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002384:Catalysis; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000235:genetics; D004563:Electrochemistry; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis / Q000737:chemistry; D009243:NAD / Q000032:analysis / Q000737:chemistry; D010084:Oxidation-Reduction; D020641:Polymorphism, Single Nucleotide
chemical_list: D004277:DNA, Single-Stranded; D009243:NAD; D006108:Graphite; D006861:Hydrogen Peroxide