title: Electrochemical detection of dopamine based on pre-concentration by graphene nanosheets.
abstract: Herein, graphene nanosheets (GNS) were synthesized, by a green and facile method based on reduction by glucose, and characterized. Afterwards, a carbon paste electrode (CPE) was modified with GNS by casting and drying GNS on top of the CPE (CPE/GNS). The behavior of the CPE/GNS towards dopamine (DA) and ascorbic acid (AA) was investigated by electrochemical methods and the obtained results showed that the CPE/GNS had adsorbed only DA. Based on this behavior, the DA molecules were pre-concentrated on top of the CPE/GNS, followed by stripping in DA free solution. Subsequent to experimental and instrumental optimization, a calibration curve from 2.0 × 10(-6) to 1.0 × 10(-3) M DA, r(2) = 0.99 (±0.01), with detection limit (DL) = 8.5 × 10(-7) M DA, sensitivity = 15.4 (±0.94) μA, and RSD = 6.1 was observed in the presence of 1.0 × 10(-3) M AA. Finally, the performance of the CPE/GNS was successfully tested in a pharmaceutical sample. This work provides a promising strategy for DA detection in the presence of biological interferences, e.g. AA, with high sensitivity and simple characteristics.
authors: Material Research School, NSTRI, 81465-1589, Isfahan, I. R. IRAN. mjmo123@yahoo.com.
authors: Mojtaba
authors: M
authors: Bagherzadeh
authors: Maryam
authors: M
authors: Heydari
mesh_terms: D004298:Dopamine / Q000032:analysis*; D055664:Electrochemical Techniques / Q000379:methods*; D006108:Graphite / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry*
chemical_list: D006108:Graphite; D004298:Dopamine