title: Identification of phylloquinone (vitamin K1) as an unknown peak in electron capture detection gas chromatograms of pyrethroid insecticide residues.
abstract: An unknown peak was observed in spinach extract during routine analysis of 7 pyrethroid insecticides by gas chromatography with electron capture detection (GC-ECD) using a DB-1 column (20 m x 0.25 mm id, 0.1 micron film thickness). It eluted later than the 7 pyrethroids, and it was also found in other agricultural crops. The intensity of the unknown peak was related to the green color of the sample: It was absent in white vegetables such as radish root or onion. Data from GC/direct deposition/Fourier-transform infrared spectroscopy (FTIR) suggested it might be phylloquinone (vitamin K1). The identity was confirmed also by using electron impact capillary GC/mass spectrometry (MS). Although phylloquinone has no halogens, it showed very high sensitivity by ECD (63Ni), responding to 10 pg.
authors.affiliation: Okayama Prefectural Institute for Environmental Science and Public Health, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Imanaka
authors.forename: M
authors.initials: M
authors.lastname: Kadota
authors.forename: K
authors.initials: K
authors.lastname: Kumashiro
authors.forename: T
authors.initials: T
authors.lastname: Mori
mesh_terms: D002849:Chromatography, Gas; D004563:Electrochemistry; D005506:Food Contamination; D008401:Gas Chromatography-Mass Spectrometry; D007306:Insecticides / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D011722:Pyrethrins / Q000032:analysis*; D017550:Spectroscopy, Fourier Transform Infrared; D014675:Vegetables / Q000737:chemistry*; D010837:Vitamin K 1 / Q000032:analysis*
chemical_list: D007306:Insecticides; D010573:Pesticide Residues; D011722:Pyrethrins; D010837:Vitamin K 1