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

Abstract

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 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 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, with coefficients of determination (R ) 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) and etofenprox (16 ng g) were detected in sediment samples. Graphical abstract Pyrethrins and pyrethroid determination in water and sediments by DLLME and LC-MS/MS.

Magnetic solid‐phase extraction or dispersive liquid–liquid microextraction for pyrethroid determination in environmental samples

“…As the contact surface is very high, the analytes are extracted almost instantaneously, producing high enrichment factors. DLLME has been applied for the microextraction of pyrethroids in several samples, including water samples [11][12][13][14][15][16][17][18][19], fruit juices [20][21][22][23][24], tea and vegetables [25][26][27], vegetable oils [28], honey [29], biological samples [30], and soil samples [31,32], using sometimes the extract of the sample as the dispersive solvent.…”

Picogram per liter quantification of pyrethroid and organophosphate insecticides in surface waters: a result of large enrichment with liquid–liquid extraction and gas chromatography coupled to mass spectrometry using atmospheric pressure chemical ionization

“…Although some methods using liquid chromatography (LC) [18,19] were developed for the analysis of pyrethroids in water samples, gas chromatography (GC) coupled to electron capture detection, to single mass spectrometry (MS) or to tandem MS has been predominantly applied for the detection of pyrethroids in water samples [16].…”

“…Method limits of quantification (MLOQs) of published studies analyzing total concentrations of pyrethroids in water samples are in the ng L -1 range for selected analytes (from several up to several hundred ng L -1 ), thereby not reaching the required AA-EQSs (see Table 2) for ecotoxicological risk assessment of pyrethroids [25,19,26,27,18,28]. These methods are lacking adequate sensitivities either because of hard ionization techniques such as EI [28], the choice of the detector (electron capture detector or high resolution MS versus triple quadrupole MS) [25,27,26] or the choice of the chromatographic system (LC versus GC) [19,18]. Only one study reports MLOQs for a limited number of pyrethroids in unfiltered surface water samples in the sub-ng L -1 range (~0.2 ng L -1 ) using ultrasound-assisted emulsification-extraction and detection by GC-negative CI-MS/MS [22].…”

Liquid Chromatography–Electron Capture Negative Ionization–Tandem Mass Spectrometry Detection of Pesticides in a Commercial Formulation

“… 28 − 30 In addition, low polarity analytes, such as pyrethroids, and those with relatively high polarity and low molecular mass, such as acidic pesticides, do not efficiently ionize in LC–MS using negative ESI. 31 , 32 …”