title: An Innovative Rapid Method for Analysis of 10 Organophosphorus Pesticide Residues in Wheat by HS-SPME-GC-FPD/MSD.
abstract: The rapid detection of pesticide residues in wheat has become a top food security priority. A solvent-free headspace solid-phase microextraction (HS-SPME) has been evaluated for rapid screening of organophosphorus pesticide (OPP) residues in wheat with high sensitivity. Individual wheat samples (1.7 g), spiked with 10 OPPs, were placed in a 4 mL sealed amber glass vial and heated at 60°C for 45 min. During this time, the OPP residues were extracted with a 50 μm/30 μm divinylbenzene (DVB)/carboxen (CAR)/plasma desorption mass spectroscopy polydimethylsiloxane (PDMS) fiber from the headspace above the sample. The fiber was then removed and injected into the GC injection port at 250°C for desorption of the extracted chemicals. The multiple residues were identified by a GC mass spectrometer detector (GC-MSD) and quantified with a GC flame photometric detector (GC-FPD). Seven spiked levels of 10 OPPs on wheat were analyzed. The GC responses for a 50 μm/30 μm DVB/CAR/PDMS fiber increased with increasing spiking levels, yielding significant (R(2) > 0.98) linear regressions. The lowest LODs of the multiple pesticide standards were evaluated under the conditions of the validation study in a range of levels from 0 (control) to 100 ng of pesticide residue per g of wheat that separated on a low-polar GC capillary column (Agilent DB-35UI). The results of the HS-SPME method were compared with the QuEChERS AOAC 2007.01 method and they showed several advantages over the latter. These included improved sensitivity, selectivity, and simplicity.
authors.affiliation: Murdoch University, School of Veterinary and Life Sciences, South St, Murdoch, WA, 6150 Australia.
authors.forename: Xin
authors.initials: X
authors.lastname: Du
authors.forename: YongLin
authors.initials: Y
authors.lastname: Ren
authors.affiliation: 40 Piddington St, Watson, Canberra, ACT 2002 Australia.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Beckett
mesh_terms: D002849:Chromatography, Gas; D013058:Mass Spectrometry; D009943:Organophosphorus Compounds / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D010783:Photometry; D052617:Solid Phase Microextraction; D014908:Triticum / Q000737:chemistry*
chemical_list: D009943:Organophosphorus Compounds; D010573:Pesticide Residues