高效液相色谱法测定水稻及其环境中茚虫威残留量

建立了高效液相色谱测定水稻及其环境中茚虫威残留量的分析方法。田水经二氯甲烷萃取,土壤、植株、稻米和稻壳经丙酮-二氯甲烷(2∶1,v/v)混合溶剂提取,弗罗里硅土净化,采用C18柱为色谱柱,以乙腈-水(60∶40,v/v)为流动相进行测定。结果表明:在0.05¹0 mg/L范围内,茚虫威峰面积与进样质量浓度呈良好的线性关系,r2=0.999 9。在高、中、低3个添加水平下,茚虫威在不同基质样品(田水、土壤、植株、稻米和稻壳)中的平均添加回收率为81.9%10 mg/L范围内,茚虫威峰面积与进样质量浓度呈良好的线性关系,r2=0.999 9。在高、中、低3个添加水平下,茚虫威在不同基质样品(田水、土壤、植株、稻米和稻壳)中的平均添加回收率为81.9%¹01.2%,标准偏差为0.2%101.2%,标准偏差为0.2%⁵.9%(n=5)。方法的定量限分别为0.01 mg/kg(田水、土壤、稻米)、0.02 mg/kg(植株)和0.04 mg/kg(稻壳)。采用该方法测定了2012年3%茚虫威超低容量液剂在湖南省宁乡县、江苏省镇江市、河南省新乡市三地水稻种植环境中的消解动态,其消解趋势符合一级动力学消解模式,茚虫威在田水中的半衰期在0.275.9%(n=5)。方法的定量限分别为0.01 mg/kg(田水、土壤、稻米)、0.02 mg/kg(植株)和0.04 mg/kg(稻壳)。采用该方法测定了2012年3%茚虫威超低容量液剂在湖南省宁乡县、江苏省镇江市、河南省新乡市三地水稻种植环境中的消解动态,其消解趋势符合一级动力学消解模式,茚虫威在田水中的半衰期在0.27².40 d之间;在土壤中的半衰期≤0.95 d;在植株中的半衰期在2.402.40 d之间;在土壤中的半衰期≤0.95 d;在植株中的半衰期在2.40¹1.34 d之间。该方法快速简便、灵敏度高、重现性好,可用于环境系统中茚虫威残留量的检测。

Determination of Indoxacarb Residue in Rice Field by HPLC

A new method was developed with HPLC to determine the indoxacarb residue in rice field. Water was extracted with methylene chloride. Soil, plants, rice and rice hull were extracted with the mixture of acetone and methylene chloride （2：1, v/v） . Then, the extracts were purified with Florisil. The reconstituted sample solution was analyzed by HPLC-PDA with a C18 column and acetonitrile-water （60：40, v/v ） was used as the mobile phase The results showed that a linear correlation of 0.999 9 was obtained with the concentration range from 0.05 to 10.00 mg/L. At three spiked concentration levels, average recoveries of indoxacarb were from 81.9% to 101.2% with the relative standard deviations （RSDs, n=5） of 0.2%-5.8% in different matrix （water, soil, plants, rice andrice hull） . The limit and 0.04 mg/kg in ric out in Hunan, Jiangs The half-lives The method is environmental Key words： of quantitation of indoxacarb was 0.01 mg/kg in water, soil and rice, 0.02 mg/kg in plants, e hull. The studies on the dynamic degradation of indoxacarb 3% LDL in rice field were carried u, Henan in 2012. The degradation curve was conformed to the first-order dynamic equation of indoxacarb were 0.27-2.40 d, ≥0.95 d and 2.40-11.34 d in water, soil and plants, respectively fast, sensitive, simple, reproducible and practical for the determination of indoxacarb residue in systems.