Determination of altretamine in human plasma with high-performance liquid chromatography

A fast, simple, and sensitive isocratic HPLC method has been developed and validated for the determination of the anticancer drug altretamine in human plasma. Spiked serum samples and clinical plasma samples are extracted with acetonitrile at 4 degrees C and the precipitate removed by filtration. The plasma sample volume required (ca. 0.2 ml) is small and the total analysis time is less than 15 min per sample (including batch-wise pre-treatment). Recovery of altretamine is 99 to 106% for pooled human serum spiked with altretamine in the range 200 ng/ml to 10 mg/ml. In this concentration range, the R.S.D. varies from 1 to 8%. The limit of quantitation is ca. 150 ng/ml for an R.S.D. of 10%. The intra-day R.S.D. for human samples spiked at 5 mg/ml varied between 1.7 and 4%; the inter-day R.S.D. at this concentration was ca. 3%. A preliminary study with one patient receiving 260 mg/m2 by mouth indicated that the peak altretamine concentration was significantly lower after a standard breakfast than in the fasting state.