ABSTRACT
Objective To assess the proficiency of water monitoring laboratory at rural, county, and provincial levels in Guangdong province, to ensure the province's drinking water monitoring results accurate and reliable. Methods State quality of certified reference materials as water arsenic, fluoride and chloride of 90 copies each were numbered and distributed to 90 monitoring laboratories in the province for testing, The measurement results of the participatory labs were evaluated through normative values and expanded uncertainty, and were compared with those of robust statistics method. Results All participatory labs had timely feedback of their measurement results. The qualified rate was higher when arsenic was tested by hydride generation atomic fluorescence spectrometry and zinc-new silver salt of sulfuric acid spectrophotometric system, while fluoride and chloride by ion chromatography. The average qualified rates of water arsenic, fluoride and chloride of the province's rural drinking water quality monitoring laboratory were 66% (59/90), 72% (65/90) and 72% (65/90), respectively.Seven participatory labs failed the proficiency testing of all three analytes and unqualified rate was 7.8% (7/90)among the ninety participated monitoring labs. The qualified rates of robust statistics method for arsenic fluoride and chloride were greater than those evaluated by the expanded uncertainty, and large deviations with small sample sizes. Conclusions The testing ability of drink-water monitoring labs in Guangdong province has improved.However, by comparison with the requirements of national quality control and testing skills, there is still a gap. It is suggested that internal quality control be included in routine inspeetion to improve laboratory testing technology.
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Objective To develop a method for the simultaneous separation and determination of 10 kinds of sedative hypnotica drugs in the functional food with high performance liquid chromatography mass spectrometry system.Methods The mobile phase consisted of acetonitrile and 15 mmol/L ammonium acetate solution(0.1% formic acid ),chromatographic column was Zobax SB C 18.Identification was based on the compound's absolute retention time,protonated molecular ion,and representative fragment ion by multiple reaction monitoring.The condition of determination was investigated and optimized.Results With this method,the linear range for the 10 drugs was 10-1 080 ?g/kg,the average recoveries ranged from 80.5%-97.1% and the detection limits were from 0.35-12.0?g/kg respectively.Conclusion The method established in the present paper is applicable to monitoring sedative hypnotica drug in the functional food.
ABSTRACT
<p><b>OBJECTIVE</b>To establish a method for the determination of curculigoside in Curculigo orchioides, a species of crude medicine.</p><p><b>METHOD</b>The methanol was used as the solvent of exatraction and the curculigoside was extracted from the crude medicine with the method of the ultrasonic vibration. Using Sep-Pak C18 cartridges to purify the solution, the curculigoside was detected by HPLC. Intersil ODS-3(150 mm x 4.6 mm, 5 microns) chromatographic column was used, mobile phase of methanol-water-ice acetic acid (45:80:1) and detect wavelength was set at UV 283 nm.</p><p><b>RESULT</b>The average recovery was 99.2% for the determination of curculigoside, RSD = 1.7% (n = 5). The content range of the curculigoside for 6 kinds of different samples was from 0.11% to 0.35%.</p><p><b>CONCLUSION</b>This method could be used to control the quality of crude medicine C. orchioides.</p>