title: Simultaneous and sensitive determination of ascorbic acid, dopamine, uric acid, and tryptophan with silver nanoparticles-decorated reduced graphene oxide modified electrode.
abstract: In this paper, we report the synthesis of silver nanoparticle-decorated reduced graphene oxide composite (AgNPs/rGO) by heating the mixture of graphene oxide and silver nitrate aqueous solution in the presence of sodium hydroxide. This material was characterized by means of X-ray diffraction, UV-vis spectroscopy, and transmission electron microscopy. AgNPs/rGO based electrochemical sensor was fabricated for the simultaneous determination of ascorbic acid, dopamine, uric acid, and tryptophan. Electrochemical studies were carried out by using cyclic voltammetry, linear sweep voltammetry, and chronoamperometry. AgNPs/rGO modified electrode exhibited excellent electrocatalytic activity, stability, sensitivity, and selectivity with well-separated oxidation peaks toward ascorbic acid, dopamine, uric acid, and tryptophan in the simultaneous determination of their quaternary mixture. The analytical performance of this material as a chemical sensor was demonstrated for the determination of ascorbic acid and dopamine in commercial pharmaceutical samples such as vitamin C tablets and dopamine injections, respectively. The applicability of this sensor was also extended in the determination of uric acid in human urine samples.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Ropar, Rupnagar 140001, India.
authors.forename: Balwinder
authors.initials: B
authors.lastname: Kaur
authors.affiliation: Faculty of Chemistry, National Autonomous University of Mexico (UNAM), Mexico.
authors.forename: Thangarasu
authors.initials: T
authors.lastname: Pandiyan
authors.affiliation: Surface Physics Division, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata 700064, India.
authors.forename: Biswarup
authors.initials: B
authors.lastname: Satpati
authors.affiliation: Department of Chemistry, Indian Institute of Technology Ropar, Rupnagar 140001, India. Electronic address: rajendra@iitrpr.ac.in.
authors.forename: Rajendra
authors.initials: R
authors.lastname: Srivastava
mesh_terms: D001205:Ascorbic Acid / Q000032:analysis*; D002384:Catalysis; D004298:Dopamine / Q000032:analysis*; D055664:Electrochemical Techniques; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D015203:Reproducibility of Results; D012834:Silver / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013059:Spectrum Analysis, Raman; D014364:Tryptophan / Q000032:analysis*; D014527:Uric Acid / Q000652:urine*; D014961:X-Ray Diffraction
chemical_list: D014527:Uric Acid; D012834:Silver; D006108:Graphite; D014364:Tryptophan; D001205:Ascorbic Acid; D004298:Dopamine
keywords: AgNPs/rGO modified electrode; Bio-molecule detection; Electro-catalysis; Non-enzymatic sensor; Simultaneous determination