Comparison of an HPLC and bioassay method to determine antimicrobial concentrations after intravenous and oral administration of enrofloxacin in four dogs.
Plasma samples of dogs given 5 mg kg-1 bodyweight of a broad spectrum antimicrobial with the active ingredient enrofloxacin were assayed by two different methods (bioassay: Escherichia coli 14 ICB 4004 on ISO sensitest agar; high performance liquid chromatography with a RP C18 column). At concentrations up to 1000 ng ml-1 a linear correlation between values obtained by the two assay methods was found. At concentrations above 1000 ng ml-1 no correlation could be determined. The main metabolite of enrofloxacin, ciprofloxacin, is an important determinant of overall antimicrobial activity and hence influences bioassay results.
Division of Animal Nutrition, University of Zürich, Switzerland.
K
K
Küng
J L
JL
Riond
S
S
Wolffram
M
M
Wanner
D000284:Administration, Oral; D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000097:blood*; D001681:Biological Assay / Q000662:veterinary*; D002851:Chromatography, High Pressure Liquid / Q000662:veterinary*; D002939:Ciprofloxacin / Q000097:blood; D004285:Dogs / Q000097:blood*; D000077422:Enrofloxacin; D024841:Fluoroquinolones; D007275:Injections, Intravenous; D015363:Quinolones / Q000008:administration & dosage / Q000097:blood*; D015610:Serum Bactericidal Test / Q000662:veterinary
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D015363:Quinolones; D000077422:Enrofloxacin; D002939:Ciprofloxacin