微波吸收介质管-微波辅助提取水果中的有机磷农药

使用自行设计的微波吸收介质管辅助加热样品, 建立了一种新的微波加速提取法, 并以正己烷为提取溶剂, 利用改装的便携式微波提取仪提取了水果中的4种有机磷农药. 将微波介质密封于玻璃管内制成微波介质管, 使微波介质可重复使用, 同时加快了提取速度. 提取产物无需纯化, 可直接用于气相色谱-质谱联用(GC-MS)分析. 自行设计改装的交直流两用便携式微波提取仪可用于野外现场的快速样品前处理. 以水果样品为例, 对提取溶剂的种类、 料液比、 提取温度及提取时间等条件进行了优化, 结果表明该方法简便、 快速且高效. 4种有机磷农药的回收率为79.4% ~107.6%, RSD<12.20%, 检出限为0.15 ~0.42 μg/kg.

Microwave Medium Tube-based Microwave-assisted Extraction of Organophosphorus Pesticides in Fruit Samples

Microwave absorption medium tube(MAMT) was firstly used to heat sample system,a new microwave-assisted extraction method was proposed and used for extracting four organophosphorus pesticides in fruit samples.In addition,a new portable microwave extraction apparatus(PMEA) was assembled in the laboratory and applied in this study.Because no polar solvent was used,the extract obtained by non-polar solvent(hexane) could be analysed directly by GC-MS without any clean-up step.The MAMT was made by sealing graphite powders in glass tube,which can be reused.The PMEA could be used in field environmental samples pretreatment.Some experimental parameters,such as type of extraction solvent,solid-to-liquid ratio,extraction temperature,and extraction time,were investigated.Four organophosphorus pesticides could be extracted from fruit samples within 8 min,and the recoveries obtained were 79.4%—107.6% with RSD <12.20%(n=3).The limits of detection for the analytes were found to be 0.15—0.42 μg/kg.The results indicated that the proposed method was simple,efficient and feasible.