PubMed | Jilin University and Fuqing Entry Exit Inspection and Quarantine Bureau
Type: | Journal: Journal of analytical methods in chemistry | Year: 2017
The existing assays for detecting brevetoxin (BTX) depend on expensive equipment with a professional operator or on an antibody with limited stability, which requires complex processes, a high cost, and a considerable amount of time. The development of an alternative detection probe is another promising research direction. This paper reports the use of aptamers binding to BTX-2 in an analytical assay using the systematic evolution of ligands by exponential enrichment (SELEX). After 12 rounds of selection, the secondary structures of 25 sequences were predicted. Compared to other aptamers, Bap5 has relatively high affinity with the lowest dissociation constant of 4.83
Su J.,Fujian CCIC Fairreach Food Safety Testing Co. |
Chen J.,Fujian CCIC Fairreach Food Safety Testing Co. |
Chen H.,Fujian CCIC Fairreach Food Safety Testing Co. |
Zhao J.,Fuqing Entry Exit Inspection and Quarantine Bureau |
And 2 more authors.
Journal of Chinese Institute of Food Science and Technology | Year: 2014
A method for the determination of chlordecone residue in aquatic products was developed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). For the method, the residue was extracted from homogenized tissue with acetonitrile-water assisted by n-hexane, separated with liquid -liquid partition. The supernatant was purified using solid phase extraction (Florisil column) prior to the GC and GC-MS analysis. Determinations were performed by using electron capture detector (ECD) in GC method and selected ion monitoring (SIM) mode in GC-MS method, then external standard method was used in the quantification. The method was convenient and rapid after investigating the conditions of pretreatment and determination. Under the optimal conditions, the detection limit of the method (RSN≥10) was 0.01 mg/kg. Tests for recovery were carried by addition of standard at concentration of 0.01 mg/kg, 0.04 mg/kg and 0.10 mg/kg, the results were 73%-110%, and the relative standard deviations were in the range of 3.5%-10.4%. The method owns the advantages of easy, fast, and more sensitive, which can meet the requirement of the determination of chlordecone residue in aquatic products.
Zhao Y.,Fujian Agriculture and forestry University |
Pan T.,Fuzhou University |
Chen Z.,Fuqing Entry exit Inspection and Quarantine Bureau
Acta Crystallographica Section E: Structure Reports Online | Year: 2010
The crystal structure of the binuclear title compound, [Cu 2(C12H11NO7)2(C 12H8N2)2], consists of a complex molecule, which lies about a crystallographic inversion centre with one half-molecule in the asymmetric unit. The CuII cation is bonded to three N atoms and three O atoms, in a Jahn-Teller-distorted octa-hedral geometry. The basal plane is defined by the two N atoms from the 1,10-phenathroline and two deprotonated O atoms of the polycarboxyl-ate ligand. The axial positions are occupied by the azane N atom and a bridging carboxyl-ate O atom from the second polycarboxyl-ate ligand. The complex molecules are linked through O - H⋯O hydrogen bonds into extended chains running parallel to .
Zheng X.,Fuqing Entry Exit Inspection and Quarantine Bureau |
Ding L.,Fuqing Entry Exit Inspection and Quarantine Bureau |
Chen Z.,Fuqing Entry Exit Inspection and Quarantine Bureau |
Guo J.,Fuqing Entry Exit Inspection and Quarantine Bureau |
Wu W.,Fuqing Entry Exit Inspection and Quarantine Bureau
Chinese Journal of Chromatography (Se Pu) | Year: 2015
A method was developed for the rapid determination of thiabendazole and carbendazim residues in concentrated fruit juices by using ultra-high performance liquid chromatography (UHPLC) coupled with triple quadrupole tandem mass spectrometry (MS/MS), and quantified by matrix-matched standard solution in external standard method. The residues in the samples were extracted by ethyl acetate, and then analyzed by using UHPLC-MS/MS in multiple reaction monitoring (MRM) mode via positive electrospray ionization with an Waters ACQUITY UP-LC BEH C18 column (50 mm ×2.1 mm, 1.7 μm) as the analytical column. Good linearities were obtained in the range of 0.5-10 μg/kg for both pesticides with correlation coefficients greater than 0.99. The recovery experiments were carried out by spiking standards into blank samples of apple, peach, orange, pear, grape juices at three levels of 0.5, 1.0 and 5.0 μg/kg. The recoveries of thiabendazole and carbendazim were from 76.98% to 108.7% with the relative standard deviations (RSD) of 2.95% -9.99%. For both pesticides in different matrices, the limits of detection (S / N = 3) were in the range of 0.12-0.23 μg/kg. Meanwhile, the pyrolysis mechanism and matrix effects for the determination of thiabendazole and carbendazim in concentrated fruit juices were investigated in this study. The method is simple, rapid and accurate, and can be used for the routine analysis of thiabendazole and carbendazim in concentrated fruit juices.
PubMed | Fuqing Entry Exit Inspection and Quarantine Bureau
Type: Journal Article | Journal: Se pu = Chinese journal of chromatography | Year: 2013
A method was developed for the determination of butene-fipronil residue in dry samples by multiple adsorption synchronous purification (MASP) -gas chromatography (GC) -mass spectrometry (MS). After extracted with 1% acetic acid-acetonitrile, the samples were pretreated with MASP method including extraction, salting-out and purification procedures, and analyzed with GC-MS under the selected ion monitoring (SIM) mode, and then quantified by matrix-match standard solution with external standard method. The results showed good linearity in the range of 2 - 100 microg/L with the correlation coefficients (r(2)) not less than 0.999. The average fortified recovery of butene-fipronil in samples was found in the range of 92.2% - 97.5% at three fortified levels from 2 to 10 microg/kg, with the relative standard deviations of 2.69% - 5.21% (n = 6). The limit of detection (S/N = 3) for butane-fipronil was 2 microg/kg and the limit of quantification (S/N = 10) was 6 microg/kg. The method is simple, rapid and accurate, and could be used for the routine analysis of butane-fipronil in dry samples. Meanwhile, the pyrolysis mechanism of butane-fipronil, as a new substance, is discussed.