Determination of Chlorocholine Chloride and Mepiquat Chloride in Soil and Water Using SPE/UPLC-MS/MS Technique

KeyWord:chlorocholine chloride  mepiquat chloride  solid phase extraction  UPLC-MS/MS  pesticide residue

Abstract:

      A novel method was developed for the determination of chlorocholine chloride£¨CCC£© and mepiquat chloride£¨MQ£© residues in soil and irrigation water based on SPE/HPLC-MS/MS technique.To investigate their enrichment efficiencies to CCC and MQ£¬4 kinds of SPE columns were used to pretreat samples£¬including silica gel column,C18 column and weak cation exchange(WCX) column.The results showed that the highest efficiency was obtained by using WCX column with 5 mL of 10 mmol/L ammonium acetate(containing 0.1% formic acid) -methanol(1¡Ã9) as elution.The separations of analytes were performed on a HILIC column£¨1.7 ¦Ìm£¬2.1 mm¡Á50 mm£© by a gradient elution using acetonitrile-10 mmol/L ammonium acetate(containing 0.1% formic acid) as moblile phase.The mean recoveries of CCC and MQ were in the range of 73%-91% and 76%-90%,respectively,with RSDs of 8.2%-12.4% and 4ª±2%-13.2%,respectively.The calibration curves of CCC and MQ were linear in the range of 1.0-50.0 ¦Ìg/L with correlation coefficients more than 0.999.The detection limits of CCC and MQ both were 0.125 ¦Ìg/kg for soil samples and 0.02 ¦Ìg/L for water samples.The method was applied in the real soil and water samples from Karashahr area£¬Xinjiang£¬and no CCC and CQ were detected.The method was reliable£¬robust and sensitive for the determination of CCC and CQ in soil and water samples.