Hunan Entry Exit Inspection and Quarantine Bureau

Changsha, China

Hunan Entry Exit Inspection and Quarantine Bureau

Changsha, China
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Chen M.-L.,Changsha University of Science and Technology | Chen J.-H.,Changsha University of Science and Technology | Ding L.,Hunan Entry Exit Inspection and Quarantine Bureau | Xu Z.,Changsha University of Science and Technology | And 3 more authors.
Analytical Methods | Year: 2017

Based on the adsorption ability of a nano-sized iron metal-organic framework (Fe-MIL-88B-NH2) to a DNA aptamer, a fluorescent biosensor for BPA was developed. In this system, the aptamer was modified with a fluorescent dye as a fluorescent DNA probe. With the introduction of an Fe-MIL-88B-NH2 aqueous solution, the aptamer probe can be adsorbed by Fe-MIL-88B-NH2, and then the fluorescence of the dye will be quenched by Fe-MIL-88B-NH2. When the fluorescent DNA probes were mixed with a sample solution containing the target BPA, a recognition process driven by BPA happened, which prevented the adsorption of the fluorescent DNA probe on Fe-MIL-88B-NH2, and made the fluorescent DNA probe freely exist in the solution. This results in the retention of the fluorescence of the solution. The limit of the proposed detection method was 4.1 × 10−14 mol L−1, with a linear working range from 5.0 × 10−14 to 2.0 × 10−9 mol L−1, and good selectivity. © The Royal Society of Chemistry.

Chen L.,Central South University of forestry and Technology | Ma S.,Kunming University of Science and Technology | Yan H.,Hunan Entry Exit Inspection and Quarantine Bureau | Wang L.,Central South University of forestry and Technology | Li J.,Central South University of forestry and Technology
Spectroscopy Letters | Year: 2017

This study aims to provide detailed and comprehensive element profiles of the traditional Chinese medicine Polygalae Radix. Based on the element profiles, chemometric methods were used to distinguish the geo-herbs of Polygalae Radix from the non-geo-herbs. Thirty-three elements in 27 samples were analyzed. Three discrimination models were constructed and compared. The regression coefficient–partial least squares–discriminant analysis and variable importance in projection–discriminant analysis models exhibited better performance. Based on the selected discrimination models, the elements lanthanum, neodymium, europium, and holmium were indicated as characteristic factors that significantly contributed to the discrimination of herbs. The information has reference value for geo-herbalism research and the quality control of Polygalae Radix. © 2017 Taylor & Francis.

Wang L.,Hunan Entry Exit Inspection and Quarantine Bureau
Chinese Journal of Chromatography (Se Pu) | Year: 2011

A new method for the determination of antioxidants, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and tertiary butylhydroquinone (TBHQ) in plastic food package by gas chromatography-electron capture detection (ECD) was developed. The antioxidants were extracted by cyclohexane with ultrasonic extraction; separated by an HP-50 + chromatographic column (30 m × 0. 53 mm × 1 μm) and quantified by external standard method with an ECD detector. The average recoveries of antioxidants were 88% - 93%, 92% - 101% and 83% - 97% for BHT, BHA and TBHQ, respectively, at the spiking levels of 3. 00 - 10.0 mg/kg. The corresponding relative standard deviations (RSDs, n = 5) were 2.01% - 2. 89%, 2. 11% - 3. 19% and 2. 99% - 4. 02%, respectively. The limits of detection (S/N = 3) were 0. 5, 0. 5 and 0. 8 mg/kg for BHT, BHA and TBHQ, respectively. The proposed method has been applied to the analysis of 5 kinds of polymer food package. The results indicated that all the above antioxidants were found in the practical polymer food package samples. Plastic food package contained BHT and BHA with the concentrations varying from 6. 3 to 7. 8 mg/kg and rubber food package contained all the three antioxidants with the concentrations varying from 9. 3 to 28. 4 mg/kg. This method is accurate, sensitive, highly reproducible and suitable for the analysis of residual antioxidants in polymer food package.

Liang M.,Tianjin University | Su R.,Tianjin University | Qi W.,Tianjin University | Yu Y.,Tianjin University | And 2 more authors.
Journal of Materials Science | Year: 2014

A novel functional bio-nanocomposite was prepared by deposition of Ag nanoparticles onto the surface of natural eggshell membrane fibers. Practically, the functional groups exposed on the fiber surface can provide locations to anchor Ag ions when immersed into metal precursor solution. The synthesized small-sized Ag nanoparticles with uniform distribution is well decorated on the surface of interwoven fibers of eggshell membrane. The effectiveness of the as-prepared AgNPs/ESM composites as a solid phase heterogeneous catalyst has been evaluated, for the first time, on the well-known 4-nitrophenol reduction to 4-aminophenol in the presence of excess borohydride. Moreover, the kinetics of the reduction reaction was investigated at different temperatures to determine the activation energy. This work provides an important example in the introduction of natural membranes for the fabrication of functional hybrid nanocomposites which could be very useful in varying fields. © 2013 Springer Science+Business Media New York.

Liang M.,Tianjin University | Liu R.,Tianjin University | Qi W.,Tianjin University | Su R.,Tianjin University | And 3 more authors.
Food Chemistry | Year: 2013

The interaction of procyanidins with proteins has aroused extensive attention due to its important relationship with the bioavailability and astringent property of polyphenols. In the present work, we have investigated the interactions of lysozyme with procyanidin dimer (B3) using various biophysical approaches, which aims to provide insights into the mechanism of protein/polyphenol aggregation. Procyanidin B3 spontaneously binds lysozyme, inducing the multilevel structural changes in lysozyme and the formation of insoluble complexes. The relationship between lysozyme aggregation and the loss of enzymatic activity was monitored using dynamic light scattering and fluorescence quenching. The influences of two carbohydrates (gum arabic and sucrose) on lysozyme/B3 aggregation were also studied. Gum arabic effectively inhibited the formation of insoluble aggregates, but was unable to restore the fluorescence and activity of lysozyme. However, sucrose concomitantly decreased the aggregate size with the recovery of fluorescence and lysozyme activity. These results proposed two probable mechanisms by which these two carbohydrates inhibit protein/polyphenol aggregation. © 2012 Elsevier Ltd. All rights reserved.

Liang M.,Tianjin University | Wang L.,Hunan Entry Exit Inspection and Quarantine Bureau | Su R.,Tianjin University | Qi W.,Tianjin University | And 3 more authors.
Catalysis Science and Technology | Year: 2013

For the first time, we demonstrated the fabrication of silver nanoparticles (NPs) in cross-linked protein crystal hybrid material with catalytic properties using a facile chemical reduction method. The macroscopic porous lysozyme crystals can be used as excellent templates for the incorporation of Ag nanoparticles. The resulting AgNP-in-lysozyme crystal composites exhibited a good catalytic activity toward nitrophenol reduction. Notably, these catalysts could be easily recovered and reused for at least five successive cycles with almost constant activity and conversion efficiency. This journal is © 2013 The Royal Society of Chemistry.

Yu Y.,Tianjin University | Su R.,Tianjin University | Wang L.,Hunan Entry Exit Inspection and Quarantine Bureau | Qi W.,Tianjin University | He Z.,Tianjin University
Medicinal Chemistry Research | Year: 2010

Dibenzo [c,h]-[1,6] naphthyridin-6-one (ARC-111) and its analogues can exhibit potent topoisomerase I targeting and antitumor activities. Quantitative structure-activity relationship (QSAR) studies on the antitumor activity of 22 ARC-111 analogues to RPMI 8402 (expressed as pIC50) were performed by using electronic, spatial, thermodynamic, and topological descriptors based on different chemometric tools including stepwise multiple linear regression (stepwise MLR), partial least squares (PLS), and artificial neural network (ANN). QSAR equations were examined using a training set of 18 compounds and an external test set of four compounds, which was divided by cluster analysis. The ANN model was the most powerful, with a square of predictive correlation coefficient R pred 2 of 0.963 for the test set; the R pred 2 values for stepwise MLR and PLS were 0.780 and 0.729, respectively. The results obtained with these models indicated that the antitumor activity of ARC-111 analogues depends strongly on electronic factors (such as sum of E-state of H-bond acceptors, dipole moment as debyes, and total energy). © 2009 Birkhäuser Boston.

Liang M.,Tianjin University | Wang L.,Hunan Entry Exit Inspection and Quarantine Bureau | Liu X.,Tianjin University | Qi W.,Tianjin University | And 4 more authors.
Nanotechnology | Year: 2013

Bio-nanomaterials fabricated using a bioinspired templating technique represent a novel class of composite materials with diverse applications in biomedical, electronic devices, drug delivery, and catalysis. In this study, Au nanoparticles (NPs) are synthesized within the solvent channels of cross-linked lysozyme crystals (CLLCs) in situ without the introduction of extra chemical reagents or physical treatments. The as-prepared AuNPs-in-protein crystal hybrid materials are characterized by light microscopy, transmission electron microscopy, x-ray diffraction, and Fourier-transform infrared spectroscopy analyses. Small AuNPs with narrow size distribution reveal the restriction effects of the porous structure in the lysozyme crystals. These composite materials are proven to be active heterogeneous catalysts for the reduction of 4-nitrophenol to 4-aminophenol. These catalysts can be easily recovered and reused at least 20 times because of the physical stability and macro-dimension of CLLCs. This work is the first to use CLLCs as a solid biotemplate for the preparation of recyclable high-performance catalysts. © 2013 IOP Publishing Ltd.

Liu Y.,Hunan University | Wu H.,Hunan University | Zhu S.,Hunan Entry Exit Inspection and Quarantine Bureau | Kang C.,Hunan University | And 4 more authors.
Chinese Journal of Chemistry | Year: 2012

A novel methodology that combines high performance liquid chromatography with photodiode-array detector (HPLC-DAD) coupled with second-order calibration method based on alternating trilinear decomposition (ATLD) algorithm was used in determination of the effective constituents such as costunolide and dehydrocostuslactone, in plasma sample and Chinese patent medicine Xiang Sha Yang Wei (XSYW) capsule. Complicated systems such as plasma and Chinese patent medicine which have intricate components are tedious to isolate and purify. The problem that chromatographic peaks are heavily overlapped among the analytes and interferents from the background matrices can be resolved, and the satisfactory quantification results have been gained with the help of the ATLD algorithm which utilized "mathematical separation" instead of partial "physical or chemical separation". Meanwhile, HPLC-MS/MS method was used to validate the accuracy of the proposed determination method. © 2012 SIOC, CAS, Shanghai & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Yu Y.-J.,Hunan University | Wu H.-L.,Hunan University | Shao S.-Z.,Hunan University | Kang C.,Hunan University | And 4 more authors.
Talanta | Year: 2011

A novel strategy that combines the second-order calibration method based on the trilinear decomposition algorithms with high performance liquid chromatography with diode array detector (HPLC-DAD) was developed to mathematically separate the overlapped peaks and to quantify quinolones in honey samples. The HPLC-DAD data were obtained within a short time in isocratic mode. The developed method could be applied to determine 12 quinolones at the same time even in the presence of uncalibrated interfering components in complex background. To access the performance of the proposed strategy for the determination of quinolones in honey samples, the figures of merit were employed. The limits of quantitation for all analytes were within the range 1.2-56.7 μg kg -1. The work presented in this paper illustrated the suitability and interesting potential of combining second-order calibration method with second-order analytical instrument for multi-residue analysis in honey samples. © 2011 Elsevier B.V. All rights reserved.

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