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Published on: March 1, 2018
Separation, pre-concentration, and HPLC analysis of methylxanthines in urine samples
Mirosława Zydroń1, Jacek Baranowski, Irena Baranowska
1Department of Analytical and General Chemistry, Silesian University of Technology, 44-100 Gliwice, Poland.
Abstract:
An SPE method, using RP18 phases, for the simultaneous extraction of caffeine, theobromine, theophylline, paraxanthine, 1-methylxanthine, 3-methylxanthine, 7-methylxanthine, 1-methyluric acid, 1,3-dimethyluric acid, 1,7-dimethyluric acid, and 1,3,7-trimethyluric acid from urine has been developed. Besides a gradient HPLC system for the analysis of the compounds of interest on a LiChrosorb RP-18 (7 microm) column with mobile phase containing 0.05% aq. solution of trifluoroacetic acid and acetonitrile has been elaborated. The procedure has been successfully applied to the analysis of methylxanthines and methyluric acids in urine of patients with chronic asthma treated with theophylline and in urine of healthy subjects.
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