▎ 摘　　要

The work reports the use of sulphur nanodots grown on graphene oxide (nS@GO) for detection of norepinephrine in presence and absence of 4-aminophenol, acetaminophen and tryptophan. The nS@GO was synthesized by one-pot method using CS2 as sulphur source using dimethylformamide (DMF) as solvent. The synthesized nanocomposite material was used for sensor application by drop-casting nS@GO (dispersed in DMF) over glassy carbon electrode. The formation of nanocomposite was confirmed using several physical characterization techniques i.e. XRD technique, Raman spectroscopy, SEM and TEM and electrochemically using cyclic voltammetry and electrochemical impedance spectroscopy. Differential pulse anodic stripping voltammetry technique was applied for quantitative determination of norepinephrine in presence and absence of 4-aminophenol, acetaminophen and tryptophan. Electrochemical impedance spectroscopy and chronoamperometry were also employed for quantitative analysis of norepinephrine. The electrochemical studies results reveal that the nS@GO based electrochemical sensor exhibits a linear response for norepinephrine in range of 0.5 to 800 mu M(in absence) and 0.5-110 mu M(in presence of other analytes) with sensitivities 4.986 mu A mu M(-1)cm(-2) and 0.407 mu A mu M(-1)cm(-2) their respective detection limit were found to be 0.26 and 0.26 mu M. The nanocomposite modified electrode response was also effectively tested in real samples without any cross reactivity. (C) 2020 Elsevier B.V. All rights reserved.