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Chen L.-Y.,Sichuan University | Liu Y.-P.,Sichuan University | Ran X.-Q.,Sichuan University | Sun C.-J.,Sichuan University | Sun C.-J.,Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment of Sichuan
Journal of Sichuan University (Medical Science Edition) | Year: 2014

Objective To establish a method for determination of sucralose in foods and beverages using high performance liquid chromatography.Methods Sucralose was extracted with water and centrifuged, and then derivatized with benzoyl chloride in alkaline medium. The ultraviolet absorbing derivatives were separated on a Hydro-RP 80Å C18 column (250 mm × 4. 6 mm, 4 μm, Synergi) using methanol-water (95 : 5 ,V/V) as mobile phase with UV detection at 232 nm.Results A good correlation (correlation coefficient=0. 999 8) between detected and actual sucralose was achieved in the range of 0. 05 to 1. 00 μg. The detection limit of sucralose was 0. 001 25 μg. The recoveries were in the range from 97. 4% to 102. 0% with relative standard deviations of less than 5. 0%. The intraday and interday relative standard deviations of the method were 1. 52% and 4. 04% , respectively.Conclusion This method is simple, rapid, and accurate without the need of special detectors, and it can be used for rapid determination of sucralose in foods and beverages. Source


Lu D.,University of Sichuan | Lu D.,Provincial Key Laboratory of Food Safety Monitoring and Risk Assessment of Sichuan | Yang Y.,U.S. Center for Disease Control and Prevention | Luo X.,University of Sichuan | And 3 more authors.
Analytical Methods | Year: 2013

A simple and easy method was established for the simultaneous determination of 73 pesticide residues in vegetables and fruits by gas chromatography-tandem mass spectrometry (GC-MS/MS). After samples were ultrasonically extracted with hexane and centrifuged, the analytes in sample solution were separated with DB-5MS column (30 m × 0.25 mm, 0.25 μm). Qualitative determination of the analytes was based on characteristic ion pairs and retention time using multiple reactions monitoring (MRM) mode. The mixed-matrices standard curves were used for quantification. The calibration curves were mostly in the range of 10-1000 μg L-1. The limits of detection (LODs) of the method were from 0.012 to 18.8 μg kg-1 and limits of quantification (LOQs) were in the range of 0.042-61.8 μg kg-1, which were much lower than the maximum residue levels (MRLs) established by European legislation. The average recoveries of the method ranged from 86.7% to 124%, 85.6% to 117%, 89.2% to 111% at three spiked levels of 0.10, 0.20, 0.50 mg kg-1 in leek samples, with relative standard deviations (RSDs) of 1.84% to 11.3%, 2.40% to 9.50%, 0.79% to 8.30%, respectively. Additionally, the method was more favorable than gas chromatography-mass spectrometry (GC-MS) in the analysis of 15 spiked samples, including ten vegetables and five fruits. Three pesticides were detected in the samples of celery and apple by the established method and the GC-MS method. © 2013 The Royal Society of Chemistry. Source


Liu Y.-P.,Sichuan University | Ran X.-Q.,Sichuan University | Chen L.-Y.,Sichuan University | Zhang J.,Sichuan University | And 5 more authors.
Journal of Sichuan University (Medical Science Edition) | Year: 2014

Objective To establish a method using precolumn ultraviolet derivatization coupled with high performance liquid chromatography (HPLC) for simultaneous determination of erythritol, xylitol, galactitol, sorbitol, mannitol, maltitol. glucose and sucrose in functional foods.Methods Target sugar alcohols and sugars in food samples were extracted in water by ultrasonic method and then reacted with benzoyl chloride to form violetabsorbing products, which were separated on a C18 column with gradient elution using methanol and water as mobile phase. The experiment was performed using a flow rate of 1. 00 mL/min, column temperature at 30 °C) and detected wavelength at 232 nm.Results The linear correlation coefficients of all the derivatives were more than 0. 999. The detection limits of the method were as low as 2. 2 μg/mL. The average recoveries were 89. 6%-117. 0%, with intraday relative standard derivations lower than 5%.Conclusion This method is simple, inexpensive and easy to operate and it is suitable for the determination of sugar alcohols and glucose and sucrose in functional foods. Source

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