Simultaneous determination of pyrethroids and pyrethrins by dispersive liquid-liquid microextraction and liquid chromatography triple quadrupole mass spectrometry in environmental samples

摘要

A simple and environmentally friendly dispersive liquid-liquid microextraction (DLLME) method coupled with electrospray ionization liquid chromatography triple quadrupole mass spectrometry (LC-QqQ-MS/MS) was developed for the simultaneous determination of 17 synthetic and natural pyrethroids. A comparison of solid-phase extraction (SPE) versus DLLME for water samples and only "dilute and shoot" versus the additional extract cleanup by DLLME for sediment samples is reported. Chloroform was the extracting solvent in the DLLME technique for both water and sediment samples. Ultrasonic energy was applied to fully extract the analytes into fine droplets, providing high recoveries in short times. Method detection limits (MDLs) ranged from 0.12 to 0.62 ng L-1 and recoveries from 70 to 119% with RSD values 2-15% (n = 5) for water samples. In sediment samples, MDLs ranged from 0.50 to 2.50 ng g(-1) and recoveries from 71 to 112% with RSDs 2-16% (n = 5). The proposed method showed a good linearity within the range of 10-500 ng mL(-1), with coefficients of determination (R-2) higher than 0.99. Matrix effects were observed for most compounds in water and sediment (ME% < -10%). The proposed methodology was applied for the analysis of water and sediment samples from Albufera wetland and Turia River. Acrinathrin (48 ng g(-1)) and etofenprox (16 ng g(-1)) were detected in sediment samples.