Determination of Trace Amounts of Mesotrione in Water by Solid Phase Extraction and High Performance Liquid Chromatography

KeyWord:mesotrione  solid phase extraction  high performance liquid chromatography£¨HPLC£©  acetonitrile  water

Abstract:

      A solid phase extraction coupled with high performance liquid chromatographic£¨HPLC£© method was developed for the determination of trace amounts of mesotrione in water.The pH values of the samples were initially adjusted to 3.0-4.0 with phosphoric acid£¬and then enriched and purified with a C18 solid-phase extraction column.The mesotrione fraction was eluted with acetonitrile-water£¨1¡Ã1£© and then concentrated to 10 mL.Mesotrione was determined by HPLC equipped with a Thermo Hypersil-C18 column£¨250 mm¡Á4.6 mm£¬5 ¦Ìm£©£¬by using a mixture of acetonitrile-phosphoric acid solution£¨45¡Ã55£¬pH 3.0£© as mobile phase at a constant flow of 0.5 mL/min.The column temperature was set at 30 ¡æ and the wavelength of ultraviolet£¨UV£© detection was set at 233 nm.The experimental results showed that a good linear relationship£¨r£¾0.999 7£© between peak area and mesotrione concentration was obtained in the range of 0.4-20 ¦Ìg?L-1.The method detection limit for mesotrione was 0.039 ¦Ìg?L-1.The average recoveries were in the range of 90.3%-94.7% at spiked levels of 1£¬5,10 ¦Ìg?L-1 with relative standard deviations of 3.5%-4.6%.The method was applied in the determination of trace amounts of mesotrione in surface water and wastewater with recoveries of 89.9%-93.2% at spiked amounts of 5 ¦Ìg?L-1 and 10 ¦Ìg?L-1.The method showed the advantages of simplicity£¬ rapidness and sensitivity£¬and was suitable for the determination of trace amounts of mesotrione in water.