title: A graphene-based electrochemical sensor for sensitive determination of caffeine.
abstract: An electrochemical sensor based on the electrocatalytic activity of graphene (Gr) for sensitive detection of caffeine is presented. The electrochemical behaviors of caffeine on Nafion-Gr modified glassy carbon electrode (Nafion-Gr/GCE) were investigated by cyclic voltammetry and differential pulse voltammetry. The results showed that the Nafion-Gr/GCE exhibited excellent electrocatalytic activity to caffeine. Caffeine can be effectively accumulated at Nafion-Gr/GCE and produce a sensitive anodic peak. Such electrocatalytic behavior of Gr is attributed to its unique physical and chemical properties, e.g., subtle electronic characteristics and strong adsorptive capability. This electrochemical sensor shows an excellent performance for detecting caffeine with a detection limit of 1.2×10(-7) M (S/N=3), a reproducibility of 5.2% relative standard deviation, and a satisfied recovery from 98.6% to 102.0%. The sensor shows great promise for simple and sensitive determination of caffeine.
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, 237#, Chang An Road, Xinyang 464000, China.
authors.forename: Jun-Yong
authors.initials: JY
authors.lastname: Sun
authors.forename: Ke-Jing
authors.initials: KJ
authors.lastname: Huang
authors.forename: Shuai-Yun
authors.initials: SY
authors.lastname: Wei
authors.forename: Zhi-Wei
authors.initials: ZW
authors.lastname: Wu
authors.forename: Fang-Ping
authors.initials: FP
authors.lastname: Ren
mesh_terms: D002110:Caffeine / Q000032:analysis* / Q000737:chemistry; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D057230:Limit of Detection; D015394:Molecular Structure
chemical_list: D002110:Caffeine; D006108:Graphite