title: Rapid screening of residual pesticides on fruits and vegetables using thermal desorption electrospray ionization mass spectrometry.
abstract: BACKGROUND
  Conventional mass spectrometry is encumbered by laborious and inconvenient sample pretreatment. Ambient thermal desorption electrospray ionization mass spectrometry (TD-ESI-MS) is most noted for its rapid, simple, and sensitive detection capabilities. In this study, TD-ESI-MS was used to rapidly characterize residual pesticides on the surfaces of fruits and vegetables.
  
  
  METHODS
  A direct sampling probe was used to obtain analytes from sample surfaces. MS and MS/MS analyses were performed on fruits and vegetables via TD-ESI-MS. External calibration curves and reproducibility tests were performed using liquid pesticide standards. Pesticide decay and distribution on samples was studied, as well as the removal of residual pesticides via soaking in water or detergent baths.
  
  
  RESULTS
  Since sample pretreatment was unnecessary, an analysis was completed in approximately 15 s or less, with no visible sample damage. Mass spectra were obtained for 22 pesticides. Linear calibrations (R(2) from 0.9414-0.999) had limits of detection as low as 0.5 µg·L(-1), with satisfactory reproducibilities for liquids and solids. Pesticides on sample surfaces decayed over 2 weeks under ambient conditions. Residual pesticides localized at the fruit peel. Detergent baths removed more pesticide than water baths.
  
  
  CONCLUSIONS
  TD-ESI-MS was used to rapidly screen residual pesticides in liquids and solids. Pesticides were found on fruits and vegetables, where the decay, distribution, and removal of pesticides on samples were also explored. Due to short analysis times, the technique allows for high-throughput analyses for applications in food and environmental safety.
authors: Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung, Taiwan.
authors: Christopher
authors: C
authors: Shiea
authors: Yeou-Lih
authors: YL
authors: Huang
authors: De-Lin
authors: DL
authors: Liu
authors: Chih-Chang
authors: CC
authors: Chou
authors: Jo-Han
authors: JH
authors: Chou
authors: Peng-Yu
authors: PY
authors: Chen
authors: Jentaie
authors: J
authors: Shiea
authors: Min-Zong
authors: MZ
authors: Huang
mesh_terms: D005638:Fruit / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis*; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry; D014675:Vegetables / Q000737:chemistry*; D014867:Water
chemical_list: D010573:Pesticide Residues; D014867:Water