title: [Development and performance evaluation of a GC-FPD method for quantification of ethephon in feeds].
abstract: An analytical method of ethephon in feeds by GC-FPD was developed. Ethephon was extracted with ethyl acetate-hydrochloric acid (100 : 1) from feed samples. The extract was treated with added trimethylsilyldiazomethane in acetone-acetic acid (99 : 1) and this methylation procedure was repeated three times. Methylated ethephon was cleaned up on a graphitized carbon mini-column and a silicagel mini-column, and determined by GC-FPD. A method performance study in 7 laboratories was conducted with three kinds of samples spiked with ethephon at 10 mg/kg, 1 mg/kg and 0.5 mg/kg. The recovery of ethephon ranged from 81.8% to 90.8% (the reproducibility standard deviation (RSDr) were within 11%) and HorRat values were 0.58 to 0.94. The limit of detection (S/N≧3) and the limit of quantitation (S/N≧10) of ethephon in samples except hay were 0.02 mg/kg and 0.05 mg/kg, respectively. In the case of hay, the corresponding values were 0.2 mg/kg and 0.5 mg/kg, respectively.
authors.affiliation: Food and Agricultural Materials Inspection Center, Sapporo Regional Center, Sapporo-shi, Hokkaido, Japan. mitsunori_yakata@nm.famic.go.jp
authors.forename: Mitsunori
authors.initials: M
authors.lastname: Yakata
authors.forename: Ryouzo
authors.initials: R
authors.lastname: Kuramitsu
authors.forename: Shigehiro
authors.initials: S
authors.lastname: Kai
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kudo
authors.forename: Ryousuke
authors.initials: R
authors.lastname: Yamoto
authors.forename: Shingo
authors.initials: S
authors.lastname: Matsuo
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D002849:Chromatography, Gas / Q000379:methods*; D009943:Organophosphorus Compounds / Q000032:analysis*; D010937:Plant Growth Regulators / Q000032:analysis*
chemical_list: D009943:Organophosphorus Compounds; D010937:Plant Growth Regulators; C005073:ethephon