High performance liquid chromatographic determination of 123-I labeled tamoxifen metabolites in human plasma

A high-performance liquid chromatographic procedure for the quantitation of [I-123]Iodomethyl-N, N-diethyltamoxifen (ITX), a radioligand for human bre ast cancer imaging, in human plasma is described. Separation was effected o n a RP-C18 column, using a mixture of acetonitrile-water-triethylamine (70/ 30/0.5, v/v). ITX was rapidly cleared from human plasma and metabolites app eared as early as 7.5 min p.i. Quantitative assessment of metabolites in pl asma over time allowed recalculation of the ITX plasma time-activity curve. Implications of ITX metabolite formation for breast tumour imaging are dis cussed. (C) 2001 Elsevier Science Inc. All rights reserved.