该文建立了快速测定畜肉中阿苯达唑及其代谢物(阿苯达唑砜、阿苯达唑亚砜、阿苯达唑-2-氨基砜)残留量的超高效液相色谱-串联质谱的分析方法。试样用乙腈提取,经QuEChERS试剂净化,通过Agilent ZORBAX Eclipse Plus C 18色谱柱分离,在正...该文建立了快速测定畜肉中阿苯达唑及其代谢物(阿苯达唑砜、阿苯达唑亚砜、阿苯达唑-2-氨基砜)残留量的超高效液相色谱-串联质谱的分析方法。试样用乙腈提取,经QuEChERS试剂净化,通过Agilent ZORBAX Eclipse Plus C 18色谱柱分离,在正离子多反应监测模式下分析,外标法定量。实验结果表明,阿苯达唑及其代谢物在各自的线性范围内线性关系良好(R ^(2)>0.998),检出限0.1~1μg/kg,在空白样品中进行3个浓度水平的添加实验,添加范围为0.1~10μg/kg,日内(n=6)平均回收率在81.9%~109.8%,日间(n=3)平均回收率在81.8%~99.0%,精密度为1.8%~14.4%。该方法操作简单、快速、准确、灵敏度高,重现性好,回收率高且稳定,检测限及定量限低于现有检测方法要求,可用于畜肉中阿苯达唑及其代谢物残留量的定性和定量分析。展开更多
Increasing use of pyrethroid insecticides has resulted in concerns regarding potential effects on human health and ecosystems. Cypermethrin and its metabolite 3-phenoxybenzoic acid(PBA) have exerted adverse biological...Increasing use of pyrethroid insecticides has resulted in concerns regarding potential effects on human health and ecosystems. Cypermethrin and its metabolite 3-phenoxybenzoic acid(PBA) have exerted adverse biological impacts on the environment;therefore,it is critically important to develop different methods to enhance their degradation. In this study,incubation experiments were conducted using samples of an Aquic Inceptisol supplied with nitrogen(N) in the form of NH4NO3 at different levels to investigate the effect of nitrogen on the degradation of cypermethrin and PBA in soil. The results indicated that appropriate N application can promote the degradation of cypermethrin and PBA in soil. The maximum degradation rates were 80.0% for cypermethrin after 14 days of incubation in the treatment with N at a rate of 122.1 kg ha-1 and 41.0% for PBA after 60 days of incubation in the treatment with N at a rate of 182.7 kg ha-1. The corresponding rates in the treatments without nitrogen were 62.7% for cypermethrin and 27.8% for PBA. However,oversupplying N significantly reduced degradation of these compounds. Enhancement of degradation could be explained by the stimulation of microbial activity after the addition of N. In particular,dehydrogenase activities in the soil generally increased with the addition of N,except in the soil where N was applied at the highest level. The lower degradation rate measured in the treatment with an oversupply of N may be attributed to the microbial metabolism shifts induced by high N.展开更多
文摘该文建立了快速测定畜肉中阿苯达唑及其代谢物(阿苯达唑砜、阿苯达唑亚砜、阿苯达唑-2-氨基砜)残留量的超高效液相色谱-串联质谱的分析方法。试样用乙腈提取,经QuEChERS试剂净化,通过Agilent ZORBAX Eclipse Plus C 18色谱柱分离,在正离子多反应监测模式下分析,外标法定量。实验结果表明,阿苯达唑及其代谢物在各自的线性范围内线性关系良好(R ^(2)>0.998),检出限0.1~1μg/kg,在空白样品中进行3个浓度水平的添加实验,添加范围为0.1~10μg/kg,日内(n=6)平均回收率在81.9%~109.8%,日间(n=3)平均回收率在81.8%~99.0%,精密度为1.8%~14.4%。该方法操作简单、快速、准确、灵敏度高,重现性好,回收率高且稳定,检测限及定量限低于现有检测方法要求,可用于畜肉中阿苯达唑及其代谢物残留量的定性和定量分析。
基金the National Key Basic Research Program of China (No.2002CB410810) and the PPI/PPIC Chinaprogram.
文摘Increasing use of pyrethroid insecticides has resulted in concerns regarding potential effects on human health and ecosystems. Cypermethrin and its metabolite 3-phenoxybenzoic acid(PBA) have exerted adverse biological impacts on the environment;therefore,it is critically important to develop different methods to enhance their degradation. In this study,incubation experiments were conducted using samples of an Aquic Inceptisol supplied with nitrogen(N) in the form of NH4NO3 at different levels to investigate the effect of nitrogen on the degradation of cypermethrin and PBA in soil. The results indicated that appropriate N application can promote the degradation of cypermethrin and PBA in soil. The maximum degradation rates were 80.0% for cypermethrin after 14 days of incubation in the treatment with N at a rate of 122.1 kg ha-1 and 41.0% for PBA after 60 days of incubation in the treatment with N at a rate of 182.7 kg ha-1. The corresponding rates in the treatments without nitrogen were 62.7% for cypermethrin and 27.8% for PBA. However,oversupplying N significantly reduced degradation of these compounds. Enhancement of degradation could be explained by the stimulation of microbial activity after the addition of N. In particular,dehydrogenase activities in the soil generally increased with the addition of N,except in the soil where N was applied at the highest level. The lower degradation rate measured in the treatment with an oversupply of N may be attributed to the microbial metabolism shifts induced by high N.
