[Determination of plasma ethambutol with liquid chromatography and ultraviolet spectrophotometry].
The method presented here is based on the ability of ethambutol to give chelates with divalent cationic metals. With copper salts, the chelate presents a characteristic ultraviolet absorbance at 270 nm, making it possible to titrate ethambutol extracted from plasma with chloroform in alkaline medium. The column which was used contained silica (LiChrosorb Si 60, 5 microns) and the mobile phase was a mixture of equal parts of water and acetonitrile, containing copper sulphate and ammonia. The internal standard was a lower homologue of ethambutol with the same chelating ability. The detection limit was 0.15 mg/l. No interference with other antitubercular agents was observed.
D000641:Ammonia / Q000032:analysis; D002850:Chromatography, Gel; D002853:Chromatography, Liquid; D003300:Copper / Q000032:analysis; D004977:Ethambutol / Q000097:blood*; D006801:Humans; D013056:Spectrophotometry, Ultraviolet
D000641:Ammonia; D003300:Copper; D004977:Ethambutol
Détermination de l'éthambutol plasmatique par chromatographie liquide et détection spectrophotométrique ultraviolette.