A multi-residue method for the determination of organochlorine pesticides in fish feed samples was developed and optimized. The method is based on a cleanup step of the extracted fat, carried out by liquid–liquid extraction on diatomaceous earth cartridge with n-hexane/acetonitrile (80/20, v/v) followed by solid phase extraction (SPE) with silica gel–SCX cartridge, before the identification and quantification of the residues by gas chromatography–triple quadrupole tandem spectrometry (GC–MS/MS). Performance characteristics, such as accuracy, precision, linear range, limits of detection (LOD) and quantification (LOQ), for each pesticide were determined. Instrumental LODs ranged from 0.01 to 0.11gL−1, LOQs were in the range of 0.02–0.35gL−1, and calibration curves were linear (r2 > 0.999) in the whole range of explored concentrations (5–100gL−1). Repeatability values were in the range of 3–15%, evaluated from the relative standard deviation of six samples spiked at 100gkg−1 of fat, and in compliance with that derived by the Horwitz’s equation. No matrix effects or interfering substances were observed in fish feed analyses. The proposed method allowed high recoveries (92–116%) of spiked extracted fat samples at 100gkg−1, and very low LODs (between 0.02 and 0.63gkg−1) and LOQs (between 0.05 and 2.09gkg−1) determined in fish feed samples.
Multi-residue method for the determination of organochlorine pesticides in fish feed based on a cleanup approach followed by gas chromatography-triple quadrupole tandem mass spectrometry
PALERMO, CARMEN;CENTONZE, DIEGO
2010-01-01
Abstract
A multi-residue method for the determination of organochlorine pesticides in fish feed samples was developed and optimized. The method is based on a cleanup step of the extracted fat, carried out by liquid–liquid extraction on diatomaceous earth cartridge with n-hexane/acetonitrile (80/20, v/v) followed by solid phase extraction (SPE) with silica gel–SCX cartridge, before the identification and quantification of the residues by gas chromatography–triple quadrupole tandem spectrometry (GC–MS/MS). Performance characteristics, such as accuracy, precision, linear range, limits of detection (LOD) and quantification (LOQ), for each pesticide were determined. Instrumental LODs ranged from 0.01 to 0.11gL−1, LOQs were in the range of 0.02–0.35gL−1, and calibration curves were linear (r2 > 0.999) in the whole range of explored concentrations (5–100gL−1). Repeatability values were in the range of 3–15%, evaluated from the relative standard deviation of six samples spiked at 100gkg−1 of fat, and in compliance with that derived by the Horwitz’s equation. No matrix effects or interfering substances were observed in fish feed analyses. The proposed method allowed high recoveries (92–116%) of spiked extracted fat samples at 100gkg−1, and very low LODs (between 0.02 and 0.63gkg−1) and LOQs (between 0.05 and 2.09gkg−1) determined in fish feed samples.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
