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Chen R.,East China Institute of Technology | Lilin S.,East China Institute of Technology | Yang S.-P.,East China Institute of Technology | Shen-Tu J.-L.,Taizhou Entry Exit Inspection and Quarantine Bureau | And 4 more authors.
Research Journal of Chemistry and Environment | Year: 2010

A homemade surface desorption atmospheric pressure chemical ionization (SDAPCI) source was coupled to a linear ion trap(LTQ) mass spectrometer for direct detection of various active constituents such as amoxicillin, norfloxacin, cefradine in powdered pharmaceutical preparations. In the SDAPCI source, ambient air (relative humidity 60%) was used as a reagent and a corona discharge was employed to generate primary reagent ions (H3P +, for instance), which were then directed to impact the sample surface for desorption and ionization at atmospheric pressure. Under the optimized experimental conditions, photolysis products of norfloxacin were rapidly detected and identified. The detection limit of 8 × 10 -13 g/cm2 was achieved in the tesing of antibiotics. Single sample analysis was completed within 1 min. The results show that multiple stage SDAPCI mass spectrometry is a useful tool for fast detection of active ingredients and trace impurities in powdered medicines, especially when the DAPCI technique is coupled with portable mass spectrometers.


Miao J.,Nanjing Agricultural University | Fa Y.,Nanjing Agricultural University | Gu B.,Taizhou Entry Exit Inspection and Quarantine Bureau | Zhu W.,Nanjing Agricultural University | Zou S.,Nanjing Agricultural University
Cytokine | Year: 2012

The intent of this study was to evaluate the active defense reaction of mouse mammary epithelial cells and the cytoprotective and anti-inflammatory properties of taurine to lipopolysaccharide (LPS)-induced disfunction in mouse mammary epithelial cells. (1) Primary cultured mouse mammary epithelial cells were stimulated with LPS for 24. h (final concentration = 0, 5, 10, 20 μg/mL). Western blotting demonstrated a significant decrease in the secretion of β-casein in the 20 μg/mL LPS treatment group (P< 0.05), while nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), lactoferrin (LF) and N-acetyl-β- d-glucosaminidase (NAGase) were all significantly increased following LPS treatment (P< 0.01). Furthermore, cell survival was significantly inhibited after treatment with 20 μg/mL LPS; however, neither 5 μg/mL nor 10 μg/mL LPS had any effect on cell survival. Therefore, a level of 10 μg/mL LPS was selected to test the protective effect of taurine on mouse mammary epithelial cells. (2) Primary cultured mouse mammary epithelial cells were treated with 0, 5, 15 or 45. mmol/L taurine for 3. h, followed by 10 μg/mL LPS for 24. h. Taurine significantly attenuated the LPS-induced increase in NAGase activity, NO concentrations and the level of TNF-α, IL-1β, IL-6 and LF. Taurine at 45. mmol/L markedly increased β-casein secretion in response to LPS-induced disfunction. This study demonstrated that the addition of taurine to a culture medium significantly inhibited the LPS-induced release of inflammatory factors and increased β-casein secretion from mammary epithelial cells, thereby providing a possible explanation for the protective effect proposed for taurine in the prevention of LPS-induced disfunction in mammary epithelial cells. © 2012 Elsevier Ltd.


Xiao X.,Taizhou Entry Exit Inspection and Quarantine Bureau | Wang J.,Taizhou Entry Exit Inspection and Quarantine Bureau | Yang J.,Taizhou Entry Exit Inspection and Quarantine Bureau | Liu T.,Taizhou Entry Exit Inspection and Quarantine Bureau | And 4 more authors.
Se pu = Chinese journal of chromatography / Zhongguo hua xue hui | Year: 2013

A novel method for rapid analysis of the migration amounts of 28 primary aromatic amines (PAAs) in aqueous food simulants (10% ethanol, 30 g/L acetic acid and 20% ethanol aqueous solution) was developed using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). After the migration test, the soaking solution was cooled down from 100 degrees C, vortexed, filtered through a hydrophilic polytetrafluoroethylene filter with a disposable syringe, and then the filtrate was analyzed by HPLC-MS/MS. A Zorbax SB-Phenyl column (250 mm x 4.6 mm, 5 microm) was selected for chromatography. The mobile phase consisted of water and 0.1% formic acid-25% acetonitrile-methanol solution with gradient elution. The 28 PAAs in aqueous food simulants were detected by tandem mass spectrometer operated in positive electrospray ionization (ESI+) and multiple reaction monitoring (MRM) mode. The limits of quantification for the 28 PAAs were between 0.002 microg/L and 10 microg/L. The linearity of the method was good with correlation coefficients (r2) greater than 0.995 over the concentration range from 5 microg/L or 10 microg/L to 100 microg/L. The average recoveries of the 28 PAAs were between 76.6% and 114% with the relative standard deviations between 1.53% and 8.97% at the levels of 10, 20, and 40 microg/L. The method shows rapid pretreatment, the lower limits of quantification, good recoveries and accuracies, and meets the requirement of European Union (EU) No 10/2011 regulation for the specific migration of PAAs. The method has been applied to analyze the 28 PAAs in different aqueous food simulants from the migration test of 30 batches of food contact material samples exported to EU.


Wang J.,Taizhou Entry Exit Inspection and Quarantine Bureau | Xiao X.,Taizhou Entry Exit Inspection and Quarantine Bureau | Chen T.,Taizhou Entry Exit Inspection and Quarantine Bureau | Liu T.,Taizhou Entry Exit Inspection and Quarantine Bureau | And 3 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2015

A novel method for simultaneous determination of total specific migration limits (SML(T)) of trimcllitic, isophthalic, terephlhalic, phthalic acid and their derivatives (1,2,4-benzenetricarboxylic anhydride, isophthaloyl chloride and terephthaloyl chloride) in food simu-lants (10% (v/v) ethanol, 20% (v/v) ethanol, 50% (v/v) ethanol, 3% (w/v) acetic acid and olive oil) was developed by high performance? liquid chromatography-ultraviolet detection (HPLC-UV). After the migration test, the soaking solution was cooled down and vortcxed. After the extraction of olive oil food simulants with 0. 1% (w/v) ammonium acetate aqueous solution, the clear aqueous solution or other aqueous food simulants was filtered through a hydropliilic polytetrafluoroethylene filter with a disposable syringe before injection. The Synergi Polar-RP column (250 mm×4.6 mm, 4 μm) and gradient elution mode were selected. The vari-able wavelength detector was set at 232 nm. The limits of quantification were 0. 1-0. 2 mg/kg; the linearity of the method was good with r2>0. 999 91 over the range from 0. 5 to 12 mg/L for aqueous food simulants or 0. 5 to 12 mg/kg for olive oil food simulants. The recoveries of them were between 94. 3% and 105% with the relative standard deviations between 0. 1% and 2. 3% at the levels of 1.25, 2.50. 6.25 mg/kg. The method shows the low limits of detection, good recoveries and accuracies, and meets the requirement of (EU)No 10/2011 regulation for the to-tal specific migration limits of triniellitic, isophthalic. terephlhalic, phthahc acids and their de-rivatives. The method has been applied to the analysis of food contact material samples.


Xu C.,Shtar Science and Technology Group | Cai H.,Taizhou Entry Exit Inspection and Quarantine Bureau | Zhang X.,China University of Petroleum - East China
Petroleum Processing and Petrochemicals | Year: 2010

A novel modification agent, emulsified SBS, was developed to prepare modified asphalt emulsion. The effect of emulsifier dosage on the storage stability of modified asphalt emulsion was studied and the results showed that the optimum emulsifier dosage was 1%. By investigating the effect of emulsified SBS dosage on the softening point, ductility and penetration of modified asphalt emulsion, an optimum emulsified SBS dosage of 6% was obtained. It was shown by the analysis results of optical microscope that when the particle size and density of the particles of SBS and asphalt were similar, the SBS particles could be dispersed uniformly in the system. Based on the above optimum dosages of emulsifier and modification agent, a modified asphalt emulsion having excellent performance was prepared.


Li C.,China Jiliang University | Wang J.,Taizhou Entry Exit Inspection and Quarantine Bureau | Zhang W.,China Jiliang University | Chen H.-C.,China Jiliang University
Guangzi Xuebao/Acta Photonica Sinica | Year: 2016

A method of simultaneously quantitative measurement of the main elements (Si and Ba) in glass by using Laser-Induced Breakdown Spectroscopy (LIBS) was established. The LIBS system is composed of a Q pulse Nd:YAG laser, an echelle grating spectrometer and an ICCD detector. We collected the LIBS spectra of 4 glass samples. The Boltzmann curves of the main elements Si and Ba were established by using free calibration method. The contents of Si and Ba in glass samples were calculated with Boltzmann curves. The relative error of the contents of Si and Ba ranged from 4.96% to 10.12% and from 4.07% to 9.62%, respectively. The standard deviation of the contents of Si and Ba ranged from 0.38% to 1.29% and from 0.54% to 1.70%, respectively. T test results showed that there was no significant difference between the measured values and the actual values. © 2016, Chinese Optical Society. All right reserved.


Cai H.,Taizhou Entry Exit Inspection and Quarantine Bureau | Wei J.,China University of Petroleum - East China | Zhang Y.,China University of Petroleum - East China | Jin C.,Taizhou Entry Exit Inspection and Quarantine Bureau
Geotechnical Special Publication | Year: 2011

The potential leachability of five asphalt binders was studied in the present study. The deionized water was the leaching agent and the content of chemical oxygen demand (COD) in the leachates was used to evaluate the leachability of asphalt binders. It was found that some components could leach from asphalt into water, and the COD in leachates increased with the leaching time. Four influence factors, including temperature, time, NaCl content, as well as pH value, were investigated to obtain the optimal conditions via orthogonal experimental design and single factor test, under which the COD of leachates reached maximum value. GC/MS analysis of the leachates showed that the oxygen compounds were the dominant part and hydrocarbon followed. © 2011 ASCE.

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