We have developed a sensitive high-performance liquid chromatography (HPLC) assay to quantitate total and lactone forms of 20(S)camptothecin (CPT) in human plasma. Lactone and total CPT were extracted using solid-phase extraction and liquid-liquid extraction, respectively. The extracted lactone samples could be stored without immediate HPLC analysis. The two forms of CPT were quantitated by reversed-phase HPLC with fluorescence detection. The extraction efficiencies were about 100% and 92% for the total and lactone forms, respectively. The lower limit of quantitation was 5.74 nM for the two forms. The method was reproducible with a mean interday and intraday variability of 6% for total CPT and 4% and 6%, respectively, for lactone CPT. The assay could effectively quantitate lactone and total CPT in patients receiving single dose and multiple doses of oral CPT.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of Chromatography B: Biomedical Applications|
|State||Published - Apr 10 1998|
- Lactone 20(S)camptothecin
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