An application of new microwave absorption tube in non-polar solvent microwave-assisted extraction of organophosphorus pesticides from fresh vegetable samples

A new self-designed microwave absorption tube was used in microwave-assisted extraction of seven organophosphorus pesticides from four kinds of vegetable samples. The non-polar solvent was used as extraction solvent, and a new portable microwave extraction apparatus was used. By sealing graphite powder in glass tube, microwave absorption tube was made and used to heat samples directly. The extracts were directly analyzed by GC–MS without any clean-up process. The effects of some experimental parameters on extraction efficiency were investigated and optimized. 3.0 g of sample, 25 mL of hexane and three microwave absorption tubes were added in the microwave extraction vessel, the extraction was carried out under 425 W irradiation power at 70 °C for 8 min. The recoveries were in the range of 76.5–109.4% and the relative standard deviations were lower than 13.1%.