高效液相色谱法检测土壤中氧化乐果残留

采用高效液相色谱法优化了土壤中的氧化乐果残留测定条件,优化结果为:色谱柱为Inertsil QDS-SP4.6*250mm,流动相为甲醇/水(V/V=10/90),溶剂为超纯水,检测波长210nm,柱温25℃,进样量为20μL,总流速1.0mL·min~(-1);氧化乐果在0.1~10.0μg·mL~(-1)范围内,其质量浓度与峰面积呈良好的线性关系(R~2=0.9992),最低检测限0.1μg·mL~(-1)。采用振荡提取法,提取剂为丙酮和乙酸乙酯,提取后的溶液以弗罗里硅土为固相萃取柱,淋洗剂为丙酮/乙腈(1/3)。采用上述方法对土壤样品进行测定,加标回收率为在70%~120%,相对标准偏差在2.08%~8.08%,说明该方法的准确度和精密度均符合农药残留分析的要求,适合土壤中氧化乐果的残留量检测。

HPLC Determination of Omethoate Content in Soil

Testing conditions for the omethoate determination byHPLC were optimized to be:Inertsil QDS-SP (4.6?250μm)at 25℃,an injection of 20μL methanol/water (V/V=10/90)as mobile phase ata flow rate of 1.0 mL·min-1 ,and the wave length of 210 nm for ultraviolet detection.A high recovery rate was achieved by using anextraction column with acetone/acetonitrile (V/V=1/3 )as the eluting agent.A linear calibration curve for the omethoate concentrations in the range of 0.1-10μg·mL-1 (R2=0.9992)with a minimal detection limit of 0.1μg ·mL-1 was established.Acetone and ethyl acetate were used as the solvents in the oscillation extraction.The recovery rate of omethoate in the soil samples ranged from 70% to 120% with a relative deviation of 2.08%-8.08%,which was within the requirements for pesticide residue analysis.It appeared that the newly developed HPLC methodology was appropriate for detecting omethoate residues in soil.