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.
Küng
K
K
Division of Animal Nutrition, University of Zürich, Switzerland.
Riond
J L
JL
Wolffram
S
S
Wanner
M
M
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