Dynamic microwave-assisted extraction online coupled with single drop microextraction of organophosphorus pesticides in tea samples.

摘要: Abstract A new method for the determination of seven organophosphorus pesticides was developed using dynamic microwave-assisted extraction online coupled with single drop microextraction prior to gas chromatographic mass spectrometry (GC–MS). The combines advantages and single-drop microextraction, which could greatly simplify operation reduce whole pretreatment time. In method, tea samples were extracted 25% ethanol aqueous solution purified acidic alumina at same time, then analytes concentrated into solvent. When completed, solvent microdrop containing enriched retracted microsyringe directly analyzed by GC–MS without any filtration or cleanup step. makes extraction, cleanup, separation, enrichment be carried out in one Several experimental parameters, including type solvent, amount dispersant, volume microwave power, flow rate investigated optimized. Under optimal conditions, good linearity observed range 2.00–500.00 μg kg−1. limits detection quantification 0.4–1.7 μg kg−1 1.1–5.6 μg kg−1, respectively. present applied analysis samples, recoveries 84.9–106.4% relative standard deviations ranging from 1.0 6.1%. results showed that a rapid feasible samples.