title: Determination of isosorbide as a metabolite of isosorbide dinitrate in human urine by capillary gas chromatography with electron-capture detection.
abstract: A method for the determination of isosorbide as a metabolite of isosorbide dinitrate at concentrations down to 200 ng/ml in human urine is described. After addition of a known amount of isomannide as internal standard to 50 microliter of urine, both compounds are extracted at basic pH into chloroform-isopropanol (4:1, v/v), which is then evaporated to dryness. They are then derivatized with heptafluorobutyric anhydride, and isosorbide is quantitated by capillary gas chromatography with electron-capture detection. A conjugate of isosorbide is determined in urine after enzymatic hydrolysis.
mesh_terms: D002849:Chromatography, Gas / Q000379:methods; D006801:Humans; D006868:Hydrolysis; D007547:Isosorbide / Q000652:urine*; D007548:Isosorbide Dinitrate / Q000378:metabolism*; D008297:Male; D013012:Sorbitol / Q000031:analogs & derivatives*
chemical_list: D013012:Sorbitol; D007548:Isosorbide Dinitrate; D007547:Isosorbide