An Integrated Strategy for Purification by Combining Solid-Phase Extraction with Dispersive-Solid-Phase Extraction for Detecting 22 Pesticides and Metabolite Residues in Fish

Abstract

A robust isotope-labeled internal standard method was established for the detection of 22 pesticides and metabolite residues in four kinds of fish; two were from freshwater fish, and two were from marine fish. Pesticides with wide application possibilities in rice in China, strong leaching to water, or high bioconcentration factors (BCF) in fish were selected. The samples were extracted with 1% acetic acid−99% acetonitrile. The extracts were first purified by solid-phase extraction (PEP-plus), cleaned with dispersive-solid-phase extraction (PSA and C18), and finally analyzed by liquid chromatography−tandem mass spectrometry (LC-MS/MS). The results showed that good linearities for the target compounds were observed in the range of 0.1−100 ng/mL, and the correlation coefficient (R 2 ) of each compound was greater than 0.99. The recoveries of the method were within 70−120% with RSDs <20% at three different spiked concentration levels (0.5, 5, and 100 ng/g). The quantitative limit of the method was 0.5− 5 ng/g. The method is shown to be sensitive and accurate and can meet the demands for the quantitative analysis of pesticides in fish.

Simultaneous determination of 27 pesticides in corn and cow matrices by ultra-performance liquid chromatography-tandem mass spectrometry

“…According to the general requirements stated in document SANTE/11312/2021, 22,23 the method was validated, encompassing linearity, sensitivity, recovery, repeatability, and matrix effects.…”

“…The addition of a suitable amount of formic acid to the extraction solvent can improve the recovery rate. 22,27 In this study, three extraction solvents, methanol, ACN, and 0.2% formic acid in acetonitrile, were compared to select the appropriate extraction solvent. The results showed that the recovery rate of methanol as extraction solvent was lower than 50% for most pesticides, while the recovery rate of cypermethrin, beta-cypermethrin, and difenocarb was higher than 120% when 0.2% FA was used.…”

Trace determination of imidacloprid and its major metabolites in wheat‐soil system

“…Inter‐day RSD was calculated using all recoveries determined on three continuous days at three spiked levels [27]. The absolute and relative recoveries were calculated according to Equations () and () [29]: $$\begin{eqnarray} && {\rm{Absolute\;recovery}}\nonumber\\ &&\quad = \frac{{{\rm{Analyte\;response\;from\;extract}}}}{{{\rm{Analyte\;response\;from\;standard}}}} \times 100\ {\rm{\% }}\end{eqnarray}$$ $$\begin{eqnarray} &&\text{Relative}\ \text{recovery}\nonumber\\ &&\quad=\frac{ \def\eqcellsep{&}\begin{array}{c} (\text{Analyte}\ \text{response}\ \text{from}\ \text{extract})/\\ (\text{IS}\ \text{response}\ \text{from}\ \text{extract})\end{array} } { \def\eqcellsep{&}\begin{array}{c}(\text{Analyte}\ \text{response}\ \text{from}\ \text{standard})/\\(\text{IS}\ \text{response}\ \text{from}\ \text{standard})\end{array} }\times 100{\rm{\% }}\end{eqnarray}$$…”

“…As IMI and its metabolites have the same constitutional formula as IMI-D 4 , the same performance was obtained during the extraction and clean-up procedures. In liquid chromatography analysis, the analytes would elute at a similar retention time and calibration with internal standards yields satisfactory results [29,43].…”

Highly-Selective Analytical Strategy for 90 Pesticides and Metabolites Residues in Fish and Shrimp Samples

“…As for the currently used pesticides, a comparison of the method with other methods in terms of analyte species, analysis time, sample pretreatment method, and LOQs is shown in Table 1 . Previous research has focused on a limited number of pesticides [ 19 , 20 , 21 , 22 ] or has been restricted to a certain class of pesticides, such as pyrethroids pesticides [ 23 ], organofluorine pesticides [ 24 ], and triazine herbicides [ 25 ], which is a disadvantage for the large-scale screening of pesticide residues in aquatic products. In this study, 90 pesticides and metabolites were selected, including 45 insecticides, 18 fungicides, 23 herbicides, 2 plant growth regulators, and 2 acaricides.…”