title: Determination of 1-(3-fluoro-4-hydroxy-5-mercaptomethyltetrahydrofuran-2-yl)-5-methyl-1H-pyrimidine-2,4-dione in rat plasma and urine by high-performance liquid chromatography.
abstract: A high-performance liquid chromatographic method using liquid-liquid extraction was developed for the determination of 1-(3-fluoro-4-hydroxy-5-mercaptomethyl-tetrahydrofuran-2-yl)-5-methyl-1H-pyrimidine-2,4-dione (l-FMAUS; I) in rat plasma and urine. A 100 microl aliquot of distilled water containing l-cysteine (100 mg/ml) was added to a 100 microl aliquot of biological sample. l-Cysteine was employed to protect binding between the 5'-thiol of I and protein in the biological sample. After vortex-mixing for 30s and adding a 50 microl aliquot of the mobile phase containing the internal standard (10 microg/ml of 3-aminophenyl sulfone), 1 ml of ethyl acetate was used for extraction. After vortex-mixing, centrifugation, and evaporating the ethyl acetate, the residue was reconstituted with a 100 microl aliquot of the mobile phase. A 50 microl aliquot was injected onto a C(18) reversed-phase column. The mobile phases, 50 mM KH(2)PO(4) (pH = 2.5):acetonitrile (85:15, v/v) for rat plasma and 50 mM KH(2)PO(4) (pH 2.5):acetonitrile:methanol (85:10:5, v/v/v) for urine samples, were run at a flow-rate of 1.2 ml/min. The column effluent was monitored by an ultraviolet detector set at 265 nm. The retention times for I and the internal standard were approximately 9.7 and 12.5 min, respectively, in plasma samples and the corresponding values in urine samples were 16.8 and 14.9 min. The quantitation limits of I in rat plasma and urine were 0.1 and 0.5 microg/ml, respectively.
authors.affiliation: College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, San 56-1, Shinlim-Dong, Kwanak-Gu, Seoul 151-742, South Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Chung
authors.forename: Yu Chul
authors.initials: YC
authors.lastname: Kim
authors.forename: Chang Hui
authors.initials: CH
authors.lastname: Koo
authors.forename: Myung Gull
authors.initials: MG
authors.lastname: Lee
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D008297:Male; D011741:Pyrimidine Nucleosides / Q000097:blood / Q000494:pharmacology* / Q000652:urine; D051381:Rats; D017207:Rats, Sprague-Dawley; D012680:Sensitivity and Specificity
chemical_list: C493853:1-(3-fluoro-4-hydroxy-5-mercaptomethyltetrahydrofuran-2-yl)-5-methyl-1H-pyrimidine-2,4-dione; D000998:Antiviral Agents; D011741:Pyrimidine Nucleosides