title: Liquid chromatographic determination of nifedipine in plasma and of its main metabolite in urine.
abstract: A high-performance liquid chromatographic method was developed for the assay of nifedipine in plasma and its main metabolite (M-I) in urine. After liquid-liquid extraction nifedipine was chromatographed in a reversed-phase system with ultraviolet detection at 238 nm. The method was sensitive to 2 ng nifedipine per ml plasma and the standard curve was linear to at least 400 ng/ml. Standard deviations did not exceed 8.5%. There was no interference with photodecomposition products or metabolites. M-I was determined in urine after liquid-liquid extraction by ion-pair chromatography with ultraviolet detection at 290 nm. The method was sensitive to 0.02 micrograms M-I per ml urine and the standard curve was linear to at least 5 micrograms/ml. Standard deviations did not exceed 5.0%. The methods were used to study nifedipine disposition in healthy volunteers.
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D004355:Drug Stability; D005260:Female; D006801:Humans; D007263:Infusions, Parenteral; D007700:Kinetics; D008297:Male; D009543:Nifedipine / Q000008:administration & dosage / Q000097:blood* / Q000652:urine; D010777:Photochemistry
chemical_list: D009543:Nifedipine