title: Electrochemical sensor based on graphene and mesoporous TiO2 for the simultaneous determination of trace colourants in food.
abstract: Currently, synthetic colourants draw much attention as food additives. This paper investigated the simultaneous electrocatalytic oxidation of sunset yellow and tartrazine, two yellow colourants commonly present in food together, with a novel voltammetric sensor based on graphene and mesoporous TiO2 modified carbon paste electrode. Due to the high accumulation effect and great catalytic capability of graphene and mesoporous TiO2, the developed sensor exhibited well-defined and separate square wave voltammetric peaks (i.e., 272 mV) for sunset yellow tartrazine. The peak currents of sunset yellow and tartrazine increased linearly with their concentration in the ranges of 0.02-2.05 μM and 0.02-1.18 μM, respectively. And the detection limit was 6.0 and 8.0 nM for sunset yellow and tartrazine, respectively. This new sensor was applied to determine sunset yellow and tartrazine in several food sample extracts. Results suggested that the proposed sensor was sensitive, rapid and reliable.
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China. gantianxynu@163.com
authors.forename: Tian
authors.initials: T
authors.lastname: Gan
authors.forename: Junyong
authors.initials: J
authors.lastname: Sun
authors.forename: Wen
authors.initials: W
authors.lastname: Meng
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.forename: Yuxia
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D001391:Azo Compounds / Q000032:analysis*; D055664:Electrochemical Techniques / Q000295:instrumentation / Q000379:methods*; D005505:Food Coloring Agents / Q000032:analysis*; D006108:Graphite / Q000737:chemistry; D057230:Limit of Detection; D016062:Porosity; D013645:Tartrazine / Q000032:analysis*; D014025:Titanium / Q000737:chemistry
chemical_list: D001391:Azo Compounds; D005505:Food Coloring Agents; C009495:titanium dioxide; D006108:Graphite; D014025:Titanium; C005842:6-hydroxy-5-((p- sulfophenyl)azo)-2-naphthalenesulfonic acid disodium salt; D013645:Tartrazine
keywords: Electrochemical sensor; Graphene; Mesoporous TiO(2); Simultaneous determination; Sunset yellow; Tartrazine