An optimized method for the quantitation of carboxyamido-triazole (CAI) in human plasma with solid phase extraction and reversed phase HPLC

The anticancer agent CAI was quantitated from human plasma using a C-18 column with a mobile phase consisting of acetonitrile and water (each containing 0.01M ammonium acetate) pumped over a gradient at a flow rate of 1.0 mL/min. The detection of CAI and the internal standard, harmine, was accomplished using a photodiode-array detector set at 264 and 323 nm, respectively. The chromatographic run time was 17.5 minutes. The plasma samples were prepared for HPLC analysis using a C-18 solid phase extraction procedure. Two calibration curves were prepared, and the assay was shown to be linear in the concentration range of 0.02 to 0.5 μg/mL for the low curve and 0.25 to 10.0 μg/mL for the high curve, with average correlation coefficients of 0.9933 and 0.9938, respectively. Intra-assay and inter-assay imprecisions were less than 10.0% with an error of accuracy of less than 11.0%. The assay was reproducible with the sensitivity needed for the prediction of CAI levels in the plasma of cancer patients.