Determination of Metalaxyl Residues in Watermelon and Banana by HPLC

摘要

A determination method for metalaxyl(MEL) residues in watermelon and banana had been established by automated solid-phase extraction(SPE) coupled with high performance liquid hromatography(HPLC). Samples were extracted by acetonitrile,homogenized,filtrated,extracted by automated solid-phase extraction(SPE),and finally purified by C18 column. The experiment was carried on SunFireTMC18 column with the mobile phase of acetonitrile-water-methanol(25∶40∶35,by vol) at the flow rate of1.0 mL/min. The detection wavelength and injection volume were set at220 nm and10 uL,respectively. The recoveries of three different concentrations(0. 02,0. 20,1. 00 mg /kg) for watermelon and banana were 94. 3%- 101. 0% and 81. 5%- 99. 6%,respectively. RSD(n = 5)were 1. 30%- 5. 29% and 2. 66%- 6. 67%,respectively. The lower detection limit for metalaxyl was 0. 006 mg /kg. This method met with the requirements of pesticide residue detection.