title: Thin-layer chromatographic determination of urinary excretion of lactulose, simplified and applied to cystic fibrosis patients.
abstract: Urinary excretion of orally administered lactulose is used as an index of intestinal permeability. We have developed a simple thin-layer chromatographic technique for measuring lactulose in urine, using silica gel 60 plates and a propanol-borate solvent system. Lactulose concentrations as low as 62.5 mg/L can be detected with high reproducibility and without interference by urinary chromogens. After oral administration, the urinary excretion of lactulose in 8 h equaled 2.33 (SD 1.86)% in 15 patients with cystic fibrosis, as compared with 0.13 (SD 0.12)% in 16 healthy subjects (P less than 0.001).
mesh_terms: D002463:Cell Membrane Permeability; D002855:Chromatography, Thin Layer; D003550:Cystic Fibrosis / Q000652:urine*; D004187:Disaccharides / Q000652:urine*; D006801:Humans; D007408:Intestinal Absorption; D007792:Lactulose / Q000652:urine*
chemical_list: D004187:Disaccharides; D007792:Lactulose