1.Determination of Paraquat in Vegetables by High Performance Liquid Chromatography
Journal of Environment and Health 1993;0(03):-
Objective To establish a method for the determination of paraquat in vegetables by high performance liquid chromatography(HPLC). Methods The HPLC separation was conducted by using an Agilent TC-C18 column (4.6 mm?250 mm,5?m). The detection wavelength was 257 nm. The eluent is the mixture of 10 mmol/L sodium heptanesulfonate and methanol (50+50) with the flow rate of 1.0 ml/min. Results The linearity of the method ranged 0.00-10.0 ?g/ml. The concentration of paraquat showed a good linear relationship (R2=0.999 4), the RSDs were 0.75%-3.65%, the rates of recovery were 96.1%-104.0%, and the limit of detection was 0.03 ?g/ml. Conclusion This simple and accurate method is applicable to the determination of paraquat in vegetables.
2.Epidemiological surveillance of Henipavirus in Chongqing
Dan PENG ; Zhilei ZENG ; Dan ZHU ; Xiao CHEN ; Jianping YU ; Mingming XU ; Yingying ZHANG ; Qunling ZHAN ; Hong ZHAI ; Peng XIE
Chinese Journal of Microbiology and Immunology 2008;28(11):1050-1054
Objective To establish nucleic acid testing techniques for detecting Nipah virus (NiV) and Hendra virus (HeV), and to test the NiV and HeV in peripheral blood collected from domestic pigs, cows and goats in Chongqing. Methods Peripheral blood samples of 580 domestic pigs, 250 cows, 180 goats were collected from Chongqing since June 2007 to June 2008. The lymphocytes were separated by density gradient centrifugation and total RNA was extracted using Trizol method for detection of NiV and HeV with one-step real-time RT-PCR. Sequence identification and analysis were performed for positive PCR prod-ucts. Virus isolation and culture were adopted for positive samples, and epidemiologic reports were submit-ted. Results Nucleic acid detections searching for NiV and HeV were successfully performed in animal blood samples collected from Chongqing. "Takeoff points" were not found in fluorescence amplification curves of all samples. Curves kept the same slope, and assays were judged as negative. Conclusion Until now, Neither NiV or HeV infection has been found in domestic animals blood samples collected from Chongqing, which suggest a lower possibility of outbreaks of Nipah disease and Hendra disease in Chongqing in the near future.