title: Determination of trace levels of steroids in blood plasma by liquid chromatography with peroxyoxalate chemiluminescence detection.
abstract: A highly sensitive and specific liquid chromatographic procedure with peroxyoxalate chemiluminescence detection has been developed for the determination of fluocortin butyl, a 3 alpha-ketocorticosteroid, in blood plasma. The technique employs dansylation of the steroid to provide a highly chemiluminescent derivative. After separation by reversed-phase liquid chromatography, reagents necessary for chemiluminescence are added, followed by detection in a conventional fluorimetric detector in which the excitation source is deactivated. The precision is 2.5% relative standard deviation at the 10 ng/ml level, and the response is linear up to at least 4 ng injected steroid. The procedure requires only 1 ml blood plasma and has a limit of detection of 100 pg/ml or 7.5 pg injected steroid. The system is reliably used for routine pharmacokinetic studies and with modifications, is applicable to other steroids as well.
mesh_terms: D001682:Biological Availability; D002853:Chromatography, Liquid / Q000379:methods; D004355:Drug Stability; D005448:Fluocortolone / Q000031:analogs & derivatives* / Q000097:blood; D006801:Humans; D007700:Kinetics; D008163:Luminescent Measurements; D013256:Steroids / Q000097:blood*
chemical_list: D013256:Steroids; D005448:Fluocortolone; C011824:fluocortin butyl ester