Objectives:The aim of this study is to investigate the electrochemical behavior of Sudan Ⅱ(Sull)using a screen-printed gold electrode(SPGE)modified with 1,4-dithiothreitol(DTT)and to determine the amount of Sudan II ...Objectives:The aim of this study is to investigate the electrochemical behavior of Sudan Ⅱ(Sull)using a screen-printed gold electrode(SPGE)modified with 1,4-dithiothreitol(DTT)and to determine the amount of Sudan II by voltammetry.Materials and Methods:A DTT-modified screen-printed gold electrode(DTT/SPGE)was fabricated and its application for differential pulse voltammetric(DPV)determination of Sull was reported.Fourier transform infrared spectroscopy(FT-IR),cyclic voltammetry and electrochemical impedance spectroscopy were used for the characterization of the modified electrode.The effects of instrumental and chemical parameters were optimized for the determination of Sull.The fabricated electrode was used for the analysis of Sull in fortified and real samples.High-performance liquid chromatography was preferred as a reference method for the evaluation of the obtained voltammetric results.Results:The electrochemical studies and FT-IR demonstrated that the SPGE was modified with DTT.The obtained peak current at DTT/SPGE was 6.67 times higher than that recorded with SPGE.At the optimized conditions of DPV in pH=2.5 of H2S04,the oxidation peak current of Sull was proportional to its concentration in:0.001-1.500 μmol L^(-1) with a detection limit of 0.0002 μmol L^(-1)(S/N=3).For the analysis of Sull,101.67%-104.33%of recovery percentage was obtained.Conclusions:A new electrode was successfully improved for the determination of Sull.This highly selective and sensitive electrode supplied the fast determination of Sull in ketchup,chili sauce and salsa dip sauce.In addition,voltammetric and chromatographic results are found to be consistent.展开更多
A new method of constant-wavelength synchronous fluorescence spectrometry for simultaneous determination of Sudan Ⅱand Sudan Ⅲ was developed with using their fluorescence phenomenon.Only one single scan is needed fo...A new method of constant-wavelength synchronous fluorescence spectrometry for simultaneous determination of Sudan Ⅱand Sudan Ⅲ was developed with using their fluorescence phenomenon.Only one single scan is needed for effective identification and quantitative determination of the two compounds simultaneously when Δλ=60 nm is chosen.The linear ranges for Sudan Ⅱ and Sudan Ⅲ were 0—3.3 and 0—2.8 μg/mL,respectively.The detection limits for Sudan Ⅱ and Sudan Ⅲ were 14 and 11 ng/mL,respectively.By using this method,Sudan Ⅱand Ⅲ in sausage samples were determined directly with the recoveries of 83.8%—109.5%.展开更多
文摘Objectives:The aim of this study is to investigate the electrochemical behavior of Sudan Ⅱ(Sull)using a screen-printed gold electrode(SPGE)modified with 1,4-dithiothreitol(DTT)and to determine the amount of Sudan II by voltammetry.Materials and Methods:A DTT-modified screen-printed gold electrode(DTT/SPGE)was fabricated and its application for differential pulse voltammetric(DPV)determination of Sull was reported.Fourier transform infrared spectroscopy(FT-IR),cyclic voltammetry and electrochemical impedance spectroscopy were used for the characterization of the modified electrode.The effects of instrumental and chemical parameters were optimized for the determination of Sull.The fabricated electrode was used for the analysis of Sull in fortified and real samples.High-performance liquid chromatography was preferred as a reference method for the evaluation of the obtained voltammetric results.Results:The electrochemical studies and FT-IR demonstrated that the SPGE was modified with DTT.The obtained peak current at DTT/SPGE was 6.67 times higher than that recorded with SPGE.At the optimized conditions of DPV in pH=2.5 of H2S04,the oxidation peak current of Sull was proportional to its concentration in:0.001-1.500 μmol L^(-1) with a detection limit of 0.0002 μmol L^(-1)(S/N=3).For the analysis of Sull,101.67%-104.33%of recovery percentage was obtained.Conclusions:A new electrode was successfully improved for the determination of Sull.This highly selective and sensitive electrode supplied the fast determination of Sull in ketchup,chili sauce and salsa dip sauce.In addition,voltammetric and chromatographic results are found to be consistent.
文摘A new method of constant-wavelength synchronous fluorescence spectrometry for simultaneous determination of Sudan Ⅱand Sudan Ⅲ was developed with using their fluorescence phenomenon.Only one single scan is needed for effective identification and quantitative determination of the two compounds simultaneously when Δλ=60 nm is chosen.The linear ranges for Sudan Ⅱ and Sudan Ⅲ were 0—3.3 and 0—2.8 μg/mL,respectively.The detection limits for Sudan Ⅱ and Sudan Ⅲ were 14 and 11 ng/mL,respectively.By using this method,Sudan Ⅱand Ⅲ in sausage samples were determined directly with the recoveries of 83.8%—109.5%.