Determination of 13 Representative Pesticides in Chinese Herbal Medicine Plants by Dispersive Solid-phase Cleanup and Gas Chromatography-Tandem Mass Spectrometry

• Published in: Fēnxī huàxué Vol. 41; no. 4; pp. 553 - 558
• Main Authors: LIU, Xiao-Liang, LI, Xue-Sheng, LIU, Shao-Wen, ZHAO, Peng-Yue, ZHOU, Li, PAN, Can-Ping
• Format: Journal Article
• Language: Chinese; English
• Published: 01.04.2013
• Subjects: Amines
• ISSN: 0253-3820
• DOI: 10.3724/SP.J.1096.2013.20574

A simple method for the determination of 13 representative pesticides in 9 Chinese herds employing modified QuEChERS(Quick, Easy, Cheap, Effective, Rugged and Safe) followed by gas chromatography-tan-dem mass spectrometric (GC-MS) analysis was developed. For the fresh or dry samples, the pesticides were extracted by acetonitrile or acetonitrile-H(2)O, respectively, and then liquid-liquid partitioning formed by adding anhydrous MgSO(4) and NaCl; followed by a simple cleanup step using multi-walled carbon nanotubes (MWC-NTs) for fresh samples extraction, and using MWCNTs and PSA (primary secondary amine) for dry samples extraction as dispersive solid phase extraction (d-SPE). The aliquot was confirmed and determined by gas chromatography with selected ion monitoring mode (SIM)- mass spectrometry. The recoveries for all the pesticides studied were from 67.9% to 100.3% with relative standard deviation(RSD) from 0.6% to 11.0% in the concentration range of 0.02-0.4 mg/kg. The limit of quantitation (LOQ) was from 0.004 mg/kg to 0.03 mg/kg, and the limit of detection (LOD) was from 0.009 mg/kg to 0.01 mg/kg. Three positive market samples, polluted by target pesticides, were screened by the developed method.