title: Determination of omeprazole and metabolites in plasma and urine by liquid chromatography.
abstract: Omeprazole, a substituted benzimidazole and a new gastric acid inhibitor, has been determined in plasma and urine, together with three of its metabolites--the sulphide, the sulphone and the hydroxy compound. The methods comprise extraction from the biological materials with methylene chloride, followed either by direct injection of the extract onto a normal-phase liquid chromatography column or evaporation, dissolution and injection onto a reversed-phase system. The compounds were detected using ultraviolet spectrometry. The absolute recoveries obtained were mostly above 95%. The minimum determinable concentration for omeprazole was 20 nmol/l in plasma (relative standard deviation 10-15%) and 50 nmol/l in urine. The metabolites could also be determined at the same levels.
mesh_terms: D000897:Anti-Ulcer Agents / Q000032:analysis* / Q000097:blood / Q000652:urine; D001562:Benzimidazoles / Q000032:analysis* / Q000097:blood / Q000652:urine; D002853:Chromatography, Liquid; D006801:Humans; D006900:Hydroxylation; D009853:Omeprazole; D013056:Spectrophotometry, Ultraviolet; D013450:Sulfones / Q000032:analysis
chemical_list: D000897:Anti-Ulcer Agents; D001562:Benzimidazoles; D013450:Sulfones; D009853:Omeprazole