A new method for determination of 3-MCPD in powder condiments was established by GC-MS method using 1,4-butanediol as an internal standard.Samples were ultrasonically extracted by ethyl acetate,and cleaned up by dispe...A new method for determination of 3-MCPD in powder condiments was established by GC-MS method using 1,4-butanediol as an internal standard.Samples were ultrasonically extracted by ethyl acetate,and cleaned up by dispersive solid-phase extraction(d-SPE) using octadecane sorbent(C18).Then the extract was derivatized with HFBI and detected by GC-MS.The detection limitation was 1.0 μg/kg,and spiked recoveries ranged from 97%-102% with RSD of 2.1%-4.1%.展开更多
【目的】建立一种多壁碳纳米管(MWCNTs)分散固相萃取气相色谱法(GC)检测蔬菜中多种农药残留的分析方法,为气相色谱法快速检测蔬菜中农药残留提供一种新的材料和应用方法。【方法】采用分散固相萃取法,10.00 g样品用10 m L乙腈提取,...【目的】建立一种多壁碳纳米管(MWCNTs)分散固相萃取气相色谱法(GC)检测蔬菜中多种农药残留的分析方法,为气相色谱法快速检测蔬菜中农药残留提供一种新的材料和应用方法。【方法】采用分散固相萃取法,10.00 g样品用10 m L乙腈提取,加入1.00 g Na Cl和4.00 g无水Mg SO4液液分离,取1 m L乙腈提取液用150 mg无水Mg SO4和15 mg多壁碳纳米管进行分散固相净化,运用气相色谱微电子俘获检测器(GC-u ECD)进行分析检测,通过添加回收试验对方法进行考察,基质匹配标准液外标法定量对蔬菜中23种农药进行检测。【结果】在0.05~1.00 mg/kg添加范围内,23种农药的添加回收率为73.0%~98.4%,相对标准偏差(RSD,n=5)为1.3%~11.0%,方法的定量限(LOQ)为0.02~0.05 mg/kg。采用该方法对市场样品进行检测,无目标农药检出。【结论】多壁碳纳米管作为分散固相吸附剂与气相色谱联用,在回收率、检出限及精密度等方面均能满足农药残留分析的要求,且成本明显低于商品化基质分散吸附剂,可在蔬菜农药残留检测分析中推广应用。展开更多
建立了分散固相萃取-超高效液相色谱-串联质谱法准确测定城市污水中六溴环十二烷(HBCD)和三-(2,3-二溴丙基)异氰脲酸酯(TBC)的方法.对萃取剂用量、萃取时间、淋洗剂、洗脱剂及色谱分离和质谱测定等条件进行了优化.优化后方法为:待测水...建立了分散固相萃取-超高效液相色谱-串联质谱法准确测定城市污水中六溴环十二烷(HBCD)和三-(2,3-二溴丙基)异氰脲酸酯(TBC)的方法.对萃取剂用量、萃取时间、淋洗剂、洗脱剂及色谱分离和质谱测定等条件进行了优化.优化后方法为:待测水样加入同位素标记的回收率内标,用0.4 g Silica、C18和HLB(1∶1∶1)混合填料分散固相萃取,回收萃取剂后用5 m L的10%的甲醇水溶液淋洗,8 m L甲醇洗脱,氮吹浓缩,加入同位素标记的进样内标测定.方法在1—200μg·L-1范围线性关系良好,HBCD和TBC的线性相关系数R2>0.9986,检出限为0.6—1.2 ng·L-1.应用该方法在某大型污水处理厂各工艺段污水中检测出了α-HBCD,浓度水平为1.3—5.4 ng·L-1.该方法操作简单、灵敏度高,尤其适合城市污水复杂基质中HBCD和TBC的分析.展开更多
文摘A new method for determination of 3-MCPD in powder condiments was established by GC-MS method using 1,4-butanediol as an internal standard.Samples were ultrasonically extracted by ethyl acetate,and cleaned up by dispersive solid-phase extraction(d-SPE) using octadecane sorbent(C18).Then the extract was derivatized with HFBI and detected by GC-MS.The detection limitation was 1.0 μg/kg,and spiked recoveries ranged from 97%-102% with RSD of 2.1%-4.1%.
文摘【目的】建立一种多壁碳纳米管(MWCNTs)分散固相萃取气相色谱法(GC)检测蔬菜中多种农药残留的分析方法,为气相色谱法快速检测蔬菜中农药残留提供一种新的材料和应用方法。【方法】采用分散固相萃取法,10.00 g样品用10 m L乙腈提取,加入1.00 g Na Cl和4.00 g无水Mg SO4液液分离,取1 m L乙腈提取液用150 mg无水Mg SO4和15 mg多壁碳纳米管进行分散固相净化,运用气相色谱微电子俘获检测器(GC-u ECD)进行分析检测,通过添加回收试验对方法进行考察,基质匹配标准液外标法定量对蔬菜中23种农药进行检测。【结果】在0.05~1.00 mg/kg添加范围内,23种农药的添加回收率为73.0%~98.4%,相对标准偏差(RSD,n=5)为1.3%~11.0%,方法的定量限(LOQ)为0.02~0.05 mg/kg。采用该方法对市场样品进行检测,无目标农药检出。【结论】多壁碳纳米管作为分散固相吸附剂与气相色谱联用,在回收率、检出限及精密度等方面均能满足农药残留分析的要求,且成本明显低于商品化基质分散吸附剂,可在蔬菜农药残留检测分析中推广应用。
文摘建立了分散固相萃取-超高效液相色谱-串联质谱法准确测定城市污水中六溴环十二烷(HBCD)和三-(2,3-二溴丙基)异氰脲酸酯(TBC)的方法.对萃取剂用量、萃取时间、淋洗剂、洗脱剂及色谱分离和质谱测定等条件进行了优化.优化后方法为:待测水样加入同位素标记的回收率内标,用0.4 g Silica、C18和HLB(1∶1∶1)混合填料分散固相萃取,回收萃取剂后用5 m L的10%的甲醇水溶液淋洗,8 m L甲醇洗脱,氮吹浓缩,加入同位素标记的进样内标测定.方法在1—200μg·L-1范围线性关系良好,HBCD和TBC的线性相关系数R2>0.9986,检出限为0.6—1.2 ng·L-1.应用该方法在某大型污水处理厂各工艺段污水中检测出了α-HBCD,浓度水平为1.3—5.4 ng·L-1.该方法操作简单、灵敏度高,尤其适合城市污水复杂基质中HBCD和TBC的分析.