Determination of Flufenacet in Rats¥“ Urine and Feces by Ultrahigh Performance Liquid Chromatography-Tandem Mass Spectrometry

KeyWord:flufenacet  ultrahigh performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)  rats  excretion

Abstract:

      An ultrahigh performance liquid chromatography-tandem mass spectrometric (UPLC-MS/MS)method was established for the determination of flufenacet in rats¥“ urine and feces.The urine and feces samples were extracted with acetonitrile.Chromatographic separation of the target compound was performed on a C18 column(50 mm¡Á4ª±6 mm,5 ¦Ìm) using ultrapure water containing 0ª±1% formic acid and acetonitrile as mobile phases at a flow rate of 0ª±6 mL¡¤min-1.The detection of flufenacet was carried out by MS with electrospray ionization in positive ionization under multiple reaction monitoring mode.There were good linear relationships for flufenacet in rats¡¯ urine and feces over the concentration ranges of 0ª±10-10ª±0 mg/L and 0ª±25-50ª±0 mg/L,with their correlation coefficients(r) larger than 0ª±99.The limits of quantitation for flufenacet in urine and feces were 0ª±10 and 0ª±25 mg/L,respectively.The intra RSDs and inter RSDs for the QC sampes were not more than 9ª±9%.The stability for flufenacet in urine ranged from 93ª±7% to 108%,and the recoveries and matrix effects were in the ranges of 97ª±0%-98ª±8% and 98ª±8%-107%,respectively.All the results met the requirements for bioanalytical method validation.The excretion kinetics in rats was also investigated after oral administration of flufenacet at a dosage of 400 mg/kg by body weight.The total accumulated excretion rate for flufenacet in urine and feces was 12ª±62% in 144 h,in which the excretion percentages for urine and feces were 1ª±12% and 10ª±13%,respectively.Results indicated that flufenacet was mainly excreted through feces.This method has the advantages of high sensitivity,selectivity and accuracy,and could be applied in the analysis of flufenacet in rats¥“ urine and feces.