Determination of flumequine in channel catfish by liquid chromatography with fluorescence detection.
Rapid methods are described for determination of flumequine (FLU) residues in muscle and plasma of farm-raised channel catfish (Ictalurus punctatus). FLU residues were extracted from tissues with an acidified methanol solution, and extracts were cleaned up on C18 solid-phase extraction cartridges. FLU concentrations were determined by liquid chromatography (LC) using a C18 analytical column and fluorescence detection (excitation, 325 nm; emission, 360 nm). Mean recoveries of FLU from fortified muscle were 87-94% at 5 levels ranging from 10 to 160 ppb (5 replicates per level). FLU recoveries from fortified plasma were 92-97% at 5 levels ranging from 20 to 320 ppb. Limits of detection (signal-to-noise ratio, 3:1) for the method as described were 3 and 6 ppb for muscle and plasma, respectively. Relative standard deviations (RSDs) for recoveries were < or = 12%. Live catfish were dosed with 14C-labeled or unlabeled FLU to generate incurred residues. Recoveries of 14C residues throughout extraction and cleanup were 90 and 94% for muscle and plasma, respectively. RSDs for incurred FLU at 2 levels in muscle and plasma ranged from 2 to 6%. The identity of FLU in incurred tissues was confirmed by LC/mass spectrometry.
Plakas
S M
SM
U.S. Food and Drug Administration, Gulf Coast Seafood Laboratory, Dauphin Island, AL 36528, USA.
el Said
K R
KR
Bencsath
F A
FA
Musser
S M
SM
Walker
C C
CC
D000818:Animals; D000890:Anti-Infective Agents / Q000032:analysis* / Q000097:blood; D002250:Carbon Radioisotopes; D002853:Chromatography, Liquid / Q000379:methods*; D004350:Drug Residues / Q000032:analysis; D024841:Fluoroquinolones; D006863:Hydrogen-Ion Concentration; D007059:Ictaluridae; D000432:Methanol; D009132:Muscles / Q000737:chemistry; D011786:Quality Control; D011807:Quinolizines / Q000032:analysis* / Q000097:blood; D013050:Spectrometry, Fluorescence
D000890:Anti-Infective Agents; D002250:Carbon Radioisotopes; D024841:Fluoroquinolones; D011807:Quinolizines; C012976:flumequine; D000432:Methanol