Hu Y.,Anhui Province Key Laboratory of Analysis and Detection for Food Safety |
Han F.,Anhui Province Key Laboratory of Analysis and Detection for Food Safety |
Lu Y.,Anhui Province Key Laboratory of Analysis and Detection for Food Safety |
Zheng P.,Anhui Province Key Laboratory of Analysis and Detection for Food Safety |
And 3 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2013
An analytical method for the simultaneous determination of clopidol, sulfadiazine, sulfamethazine, sulfametoxydiazine, sulfamethoxypyridazine, norfloxacin, ofloxacin, ciprofloxacin, enrofloxacin in chickens by ultra performance liquid chromatography coupled with tandem quadrupole mass spectrometry (UPLC-MS/MS) in positive ion mode with multiple reaction monitoring (MEM) has been developed and validated. The samples were homogenized and extracted with acetonitrile. After defatted with high speed frozen centrifugation, the supernatant solution was evaporated and the residue was dissolved with the mobile phase and defatted with.η hexane. It was then analyzed with UPLC-MS/MS. The limit of detection of this method was 0.1 μg/kg, and the limit of quantification was 0.5 μg/kg. The average recoveries (spiked at the levels of 0. 5, 1. 0, 2. 0 μg/kg) ranged from 81. 5% to 97. 6%, with the relative standard deviations between 2.1% and 8.9%. The results demonstrated that the method is simple, accurate and suitable for the identification and quantification of these drug residues in chickens.
Yu L.,Anhui Agricultural University |
Song W.,Anhui Entry and Exit Inspection and Quarantine Bureau |
Song W.,Anhui Province Key Laboratory of Analysis and Detection for Food Safety |
Lu Y.,Anhui Entry and Exit Inspection and Quarantine Bureau |
And 7 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2015
An analytical method was established for the simultaneous determination of 204 pesticide residues in tea by ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry (UPLC-Q-TOF/MS). The samples were extracted with acetonitrile, and cleaned-up by solid phase extraction (SPE) with a Carb-PSA cartridge, eluted with acetonitrile-toluene (3 :1, v/v), determined by UPLC-Q-TOF/MS and quantified by external standard method. A data base of the accurate mass numbers and a library which contains the 204 pesticides were established. The automatic retrieval of detection results was carried on according to the characteristics of the compound, such as accurate mass, retention time, isotopic ratio, and so on. Based on the above results, the qualitative identifications of the 204 pesticides were accomplished without the contrast of standard substances. The results indicated that this method can be used to determine the 204 pesticides in tea. At the three spiked levels of 10, 20, 50 μg/kg, mean recoveries for the 204 pesticides in tea were between 68.1% and 117.2%, with the relative standard deviations (RSDs) ranging from 3.1% to 18.9%. The limits of quantification for the 204 pesticides were lower than 10 μg/kg. The method has been applied to four positive samples, and the results generally accord with the detection results by the method of GB/T 23205-2008. This method has the characteristics of high efficiency, as well as high sensitivity and accuracy, which can meet the requirement of the determination of the 204 pesticides in tea.
Magnetic graphene based dispersive micro-solid-phase extraction coupled with liquid chromatography-tandem quadrupole mass spectrometry for the analysis of nine non-steroidal anti-inflammatory drugs in livestock and poultry meat
Dong C.,Hefei University of Technology |
Hu Y.,Anhui Entry Exit Inspection and Quarantine Bureau |
Hu Y.,Anhui Medical University |
Lu Y.,Anhui Entry Exit Inspection and Quarantine Bureau |
And 8 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2016
A novel analytical method was developed for the determination of nine non-steroidal anti-inflammatory drugs (NSAIDs) in meat samples by magnetic graphene nanocomposite (Fe3O4-G) based on dispersive micro-solid-phase extraction (μ-SPE) coupled with liquid chromatography-mass spectrometry detection. Samples were homogenized and extracted with acidified acetonitrile. After defatting with the high speed frozen centrifugation, the sample solutions were defatted with n-hexane followed by μ-SPE. Some important parameters influencing the extraction efficiency including the extraction time, the pH value of sample solution and the elution conditions were optimized. The limits of detection (LODs, S/N=3) of the nine NSAIDs ranged from 0.2 to 8.2 μg/kg, and the limits of quantification (LOQs, S/N=10) ranged from 0.5 to 25.4 μg/kg. The average recoveries were 83.3%-104.5% with the relative standard deviations between 1.2% and 6.8% obtained from samples spiked at LOQ, 2LOQ and 10LOQ levels. Compared with Sep-Pak Vac NH2 and Oasis HLB cartridges, Fe3O4-G has excellent purification effect, high loading amounts and good reusability. The results demonstrated that the method provide a novel pretreatment technique for the determination of NSAID residues in meat samples.
Li W.-J.,Anhui University |
Li W.-J.,Inspection and Quarantine Technology Center |
Hu Y.-Y.,Inspection and Quarantine Technology Center |
Hu Y.-Y.,Anhui Province Key Laboratory of Analysis and Detection for Food Safety |
And 7 more authors.
Gaodeng Xuexiao Huaxue Xuebao/Chemical Journal of Chinese Universities | Year: 2013
A molecular simulation method for molecularly imprinted polymerization system using triadimefon as template and acrylic amide (AM), acrylic acid (AA), methacrylic acid (MAA) and trifluoromethyl acrylic acid (TFMAA) as functional monomers was presented. The geometry conformation, energy, reaction ratio and binding energy of the pre-organization system were simulated by a semi-empirical method (PM3) and ab inito algorithm methods with Hyperchem 8.0 software. The monomer that provided the largest binding energy was then chosen for the synthesis of molecularly imprinted polymers (MIPs). The solvation energy, an intensity index of the molecular interaction between different porogens with template molecule and monomer, was calculated using density functional theory (DFT). The results show that TFMAA gives stronger hydrogen-bonding interaction with triadimefon than other monomer molecules studied, and the salvation energy for template and monomer in polar solvents is greater than that in non-polar solvents. The pre-assembled system of triadimefon and TFMAA was studied using differential UV spectra and the results indicate that one molecule triadimefon and two molecules TFMAA can form stable hydrogen-bonded complexes in chloroform. This is consistent with the predictions based on the molecular simulation. The adsorption and recognition properties for MIPs were investigated using Langmuir and Freundlich adsorption isotherm. The results can give useful information for screening molecular imprinting system and predicting the performance of MIPs.