Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
Environ Monit Assess. 2013 Oct;185(10):8451-63. doi: 10.1007/s10661-013-3186-3. Epub 2013 Apr 18.
Analysis of endosulfan, chlorpyrifos, and their nonpolar metabolites in extracts from environmental aqueous and soil samples was performed using a gas chromatography-tandem mass spectrometry (GC-MS/MS) technique. Full-scan GC-MS analysis showed poor sensitivity for some of the metabolites (endodiol and endosulfan ether). A multisegment MS/MS method was developed and MS/MS parameter isolation time, excitation time, excitation voltage, and maximum excitation energy were optimized for chosen precursor ions to enhance selectivity and sensitivity of the analysis. The use of MS/MS with optimized parameters quantified analytes with significantly higher accuracy, and detection limits were lowered to ~1/6th compared with the full-scan method. Co-eluting compounds, chlorpyrifos and chlorpyrifos oxon, were also analyzed successfully in the MS/MS mode by choosing exclusive precursor ions. Analysis of soil and water phase samples from contaminated soil slurry bioreactors showed that the MS/MS method could provide more reliable estimates of these pesticide and metabolites (especially those present in low concentrations) by annulling interferences from soil organic matter.
采用气相色谱-串联质谱（GC-MS/MS）技术对环境水样和土壤样品中的硫丹、毒死蜱及其非极性代谢物进行了分析。全扫描 GC-MS 分析显示，部分代谢物（硫丹二醇和硫丹醚）的灵敏度较差。开发了一种多段 MS/MS 方法，并对选定的前体离子进行了 MS/MS 参数隔离时间、激发时间、激发电压和最大激发能量的优化，以提高分析的选择性和灵敏度。使用优化参数的 MS/MS 定量分析物具有更高的准确性，检测限与全扫描方法相比降低了约 1/6。通过选择专属性前体离子，还成功地在 MS/MS 模式下分析了氯吡硫磷和氯吡硫磷氧。通过消除土壤有机质的干扰，MS/MS 方法可提供更可靠的估计这些农药及其代谢物（尤其是低浓度存在的代谢物）的浓度。
