title: Liquid-chromatographic determination of 5-fluorocytosine.
abstract: We report a "high-performance" liquid-chromatographic method for measuring 5-fluorocytosine in plasma and cerebrospinal fluid. After deproteinization with trichloroacetic acid, the supernates are chromatographed on a reversed-phase (C18) column. Response to concentration is linear in the range of 5 to 200 mg/L, with ultraviolet detection at 276 nm. The assay requires only 0.1 mL of plasma, is reproducible, and may be performed in less than 12 min. 5-Fluorocytosine concentrations determined by this procedure correlated well with those obtained by spectrofluorometry, although the present method is more specific with no observable interference from co-administered amphotericin B and most other commonly encountered drugs, including salicylat:. This method is applicable to the routine therapeutic monitoring of pediatric and adult patients as well as to pharmacokinetic studies.
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003596:Cytosine / Q000031:analogs & derivatives*; D005437:Flucytosine / Q000097:blood* / Q000134:cerebrospinal fluid; D006801:Humans; D013050:Spectrometry, Fluorescence
chemical_list: D003596:Cytosine; D005437:Flucytosine