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LC/MS/MS Analysis of Pesticide Residues in Dates on the Ascentis® Express RP-Amide Column after QuEChERS Extraction

LC/MS/MS Analysis of Pesticide Residues in Dates on the Ascentis® Express RP-Amide Column after QuEChERS Extraction

Conditions

sample preparation Dilute 100 µl of cleaned extract to a final volume of 1 mL in 5 mM ammonium formate/0.1% formic acid in water; transfer diluted sample to vial for LC/MS/MS analysis
sample/matrix 5 g ground dates spiked with pesticides at 10 ng/g
extraction process add 10 mL water and 10 mL acetonitrile; shake 1 hr at 2500 rpm; add contents of Supel QuE citrate extraction tube (55227-U); . (shake for 1 minute; centrifuge at 5000 rpm fo 5 minutes and draw off supernatant)
clean-up process transfer 1 mL of the extract to 2 mLSupel QuE PSA/C18 tube; shake for 1 minute; centrifuge at 5000 rpm for 3 min; draw off supernatant for analysis.
clean-up tube Supel QuE PSA/C18 (55288-U)
column Ascentis Express RP-Amide, 10 cm x 2.1 mm I.D., 2 µm particles (51576-U)
column temp. 30 C
mobile phase (A) 5 mM ammonium formate with 0.1% formic acid in water; (B) 5 mM ammonium formate with 0.1% formic acid in 95:5 acetonitrile:H2O
gradient held at 5% B from 0 to 1 min; to 100% B in 13 min; held at 100% B for 1.5 min; to 95% A in 0.5 min; held at 95% A for 1.5 min
flow rate 0.4 ml/min
injection 5 µl
detector MS, ESI (+), MRM

Description

Analysis Note The “quick, easy, cheap, effective, rugged, and safe” (QuEChERS) method can be used to analyze µltiple pesticide residues found in dates. In this study, QuEChERS extraction and cleanup using PSA/C18 were used for the analysis of pesticide residues of interest in pistachios. Average recoveries obtained for replicate samples spiked at 10 ng/g were in the range of 70-120% for 23 of the 25 pesticides analyzed.
Application Freeze dates with liquid nitrogen and grind to a homogenous mixture.
Categories Analytical Chromatography, Pesticides & Herbicides
Featured Industry Food and Beverages
Legal Information Ascentis is a registered trademark of Sigma-Aldrich Co. LLC
suitability application for LC-MS, application for SPE

Materials

     
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