Study Of A Novel Sensor For Fast And Direct Determination Of Tartrazine Based On Molecularly Imprinted Membrane

In recent years,with the increasingly widespread use of artificial dyes,food safety incidents caused by artificial dyes occurred frequently.As a kind of article azo dye,tartrazine has been used widely in food industry due to it' s low price and excellent dyeing effect.However,because of it's azo groups and the benzene rings structure,the excessive use of tartrazine may produce some hazard to human body,which lead to the use of tartrazine limited,and the events that illegal or excessive addition of artificial dyes in food products have been reported constantly.Traditional detection methods such as high performance liquid chromatography?HPLC?and UV spectrophotometry need expensive equipment,complicated sample preparation procedure and can not achieve on-site rapid detection.Therefore,development of a high sensitivity,selectivity,low cost,quickly and derectly method there is practical significance.This paper reports a novel molecularly imprinted sensor that can directly and fast detect tartrazine in practical samples whithout any sample pretreatment.The developed sensor was modified in glass carbon electrode?GCE?directly via cyclic voltammetry with m-dihydroxybenzene?m-DB?and o-Phenylenediamine?o-PD?as monomers and tatrazine as template.After eluting the template from the polymer by 50%ethanol containing 0.5mol/L H₂SO₄,the molecularly imprinted polymer can adsorbed and recognize tatrazine.K₃Fe[?CN?₆]was used as electrochemical probes and tartrazine was detect indirectly make use of "door effect".In this paper,electrochemical properties of the developed sensor in various stages in preparation process were characterized by cyclic voltammetry?CV?,different pulse voltammetry?DPV?and Electrochemical impedance spectroscopy?EIS?.The surface topography of the molecularly imprinted polymer was characterized by Scanning electron microscope?SEM?.The preparation process conditions and test conditions were optimized and the optimal experimental conditions was obtained.Under the optimum experimental conditions,the peak current and the tatrazine concentration have good linear relationship within 5×10^-9mol/L?1.1×10^-6mol/L with detection limit 3.5×10^-9mol/L.The linear equation is ip=-63.294C?TZ?+77.120 with R²=0.9918.In this study,The selectivity of the developed device was investigated and the sensor performed excellent selectivity and anti-interference.Reproducibility and stability of the developed sensor was studied.The result revealed that the device performed good reproducibility and stability.The RSD of 10 times result in the same tartrazine solution is 1.6%.The response current after 210 days was 93.11%of that of the first time.The performance of the sensor in the actual samples determination was investigated.The recovery rate of the sensor detection in soft drink samples is between 96.35%and 101.32%.This method is expected to be better applied in actual analysis.