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Tong P.,Key Laboratory of Analysis and Detection for Food Safety | Tong P.,Fuzhou University | Zhang L.,Key Laboratory of Analysis and Detection for Food Safety | Zhang L.,Fuzhou University | And 4 more authors.
Talanta | Year: 2010

In this paper, a rapid and effective method based on capillary zone electrophoresis (CZE) coupled with electrospray ionization mass spectrometry (ESI-MS) was established for the trace analysis of microcystin (MC) isomers in crude algae sample. The experimental conditions including the composition, acidity and concentration of buffer, separation voltage, injection time, and MS detection parameters were investigated in detail. A capillary separation system was as follows: a uncoated fused-silica capillary tube (50 μm i.d. × 90 cm), 40 mmol L -1 ammonium acetate solution (pH 9.86) as running buffer, 25 kV as separation voltage, 20 kV × 3 s water first and 20 kV × 20 s for sample injection. Mass analysis was performed in ESI source, with sheath gas temperature 150 °C, sheath gas pressure 10 psi, and sheath gas flow 6 L min -1. And sheath liquid was 7.5 mmol L -1 acetic acid in 50% isopropanol-water (3 μL min -1). Protonation and ammonium adduct molecular ions m/z 506.9 (MC-LR) and 532.0 (MC-YR) were used for the quantification of MCs. Under these conditions, two MCs were baseline separated within 9 min, the calibration curves were obtained in the range of 0.11-10.0 μg mL -1 and 0.16-10.5 μg mL -1 for MC-LR and MC-YR, respectively. Meanwhile, limits of detection were 0.05 and 0.08 μg mL -1 for MC-LR and MC-YR, respectively. The recoveries for the two MCs were in the range of 95.8-108%. The developed approach had been successfully applied to the analysis of MCs in crude algae samples. © 2010 Elsevier B.V. All rights reserved. Source

Chen Y.,Key Laboratory of Analysis and Detection for Food Safety | Chen Y.,Fuzhou University | Zhang J.,Key Laboratory of Analysis and Detection for Food Safety | Zhang J.,Fuzhou University | And 5 more authors.
Electrophoresis | Year: 2010

A method was developed for the chiral separation of dipeptides with two chiral centers. Although all analyzed peptides contain chromophores and they can be detected by UV-adsorption detection without any derivatization, the chiral separations were not achieved for non-derivatized peptides using the same chiral selectors and experimental conditions. In this paper, these dipeptides were precolumn derivatized by using naphthalene-2, 3-dicarboxyaldehyde as a tagging reagent. In the presence of 2-hydroxypropyl-β-CD and sodium deoxycholate, naphthalene-2,3-dicarboxyaldehyde-tagged dipeptide enantiomers were well resolved by MEKC. Good separation of all enantiomers was obtained within 14 min. The proposed method was applied to chiral separation of dipeptide enantiomers in spiked human serum samples. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA. Source

Yang H.F.,Key Laboratory of Analysis and Detection for Food Safety | Yang H.F.,Fuzhou University | Yang H.F.,Fujian Health College | Zhang Y.S.,Key Laboratory of Analysis and Detection for Food Safety | And 5 more authors.
Chinese Chemical Letters | Year: 2012

In this study, the electrochemiluminescent (ECL) behavior of Nickel(II) tetrasulfophthalocyanine (NiTSPc)/H 2O 2 on a heated indium tin oxide (ITO) electrode was investigated. The effect of pH value, electrochemical scan mode, concentration of NiTSPc and electrode surface temperature on the ECL intensities had been studied in detail. Based on the fact that the ECL of NiTSPc can be greatly enhanced by hydrogen peroxide at the ITO electrode, a new ECL biosensor for hydrogen peroxide has been developed. The possible mechanism for the ECL of NiTSPc has also been proposed. © 2012 Zhen Yu Lin. Source

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