title: Liquid chromatographic analysis of prednisolone, prednisone and their 20-reduced metabolites in perfusion media.
abstract: A reversed-phase liquid chromatographic assay was developed to quantitate prednisolone, prednisone and the 20 alpha-dihydro and 20 beta-dihydro reduced metabolites of both parent compounds in tissue culture media from in vitro perfusions of the human placental lobule. Steroids were extracted from perfusate, using reversed-phase cartridges, with average recoveries of 95.2% or greater. The internal standard for the analyses was 6 alpha-methylprednisolone. In this assay cortisol coelutes with prednisolone, however, no other significant interferences were found. Assay of each steroid was linear in the range 0-1 microgram/ml. Intra-assay coefficients of variation were measured at 10 and 750 ng/ml with ranges of 3.4% (20 alpha-dihydroprednisone) to 8.8% (20 beta-dihydroprednisolone) and 4.1% (20 beta-dihydroprednisone) to 8.8% (prednisone). The corresponding inter-assay coefficients of variation were 3.3% (20 alpha-dihydroprednisone) to 9.1% (20 beta-dihydroprednisolone) and 1.9% (prednisolone) to 3.5% (prednisone). The analyses utilized two C18 columns which were linked together and maintained at 40 degrees C.
authors.affiliation: Conjoint Internal Medicine Laboratory, Royal Brisbane Hospital, Queensland, Australia.
authors.forename: G R
authors.initials: GR
authors.lastname: Cannell
authors.forename: R H
authors.initials: RH
authors.lastname: Mortimer
authors.forename: D J
authors.initials: DJ
authors.lastname: Maguire
authors.forename: R S
authors.initials: RS
authors.lastname: Addison
mesh_terms: D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis / Q000378:metabolism; D010477:Perfusion; D010920:Placenta / Q000737:chemistry / Q000378:metabolism; D011239:Prednisolone / Q000032:analysis* / Q000378:metabolism; D011241:Prednisone / Q000032:analysis* / Q000378:metabolism; D011247:Pregnancy
chemical_list: D011239:Prednisolone; D011241:Prednisone; D006854:Hydrocortisone