FIGURE 2. HPLC profiles (absorbance at 430 nm and radioactivity after fraction collection) during synthesis of TFP-N-sucDf ester and preparation of mAb-N-sucDf after reaction of N-sucDf with ⁵⁹Fe-FeCl₃ (A), after esterification of N-sucDf-⁵⁹Fe-Fe (B), after reaction of TFP-N-sucDf-⁵⁹Fe-Fe with mAb (C), and after removal of iron from mAb-N-sucDf-⁵⁹Fe-Fe with EDTA (D). Analyses were performed with Chromspher (Chrompack) 5 C18 column (A and B) or Superdex (Pharmacia Biotech) 200 HR column (C and D). Peak 1 = unreacted ⁵⁹Fe-FeCl₃ (retention time, 3.3 min; reaction performed with an excess of 1.1 to 1); peak 2 = N-sucDf-⁵⁹Fe-Fe (retention time, 16.7 min for A and B and 39 min for C); peak 3 = TFP-N-sucDf-⁵⁹Fe-Fe (retention time, 25.9 min); peak 4 = mAb-N-sucDf-⁵⁹Fe-Fe (retention time, 23 min); peak 5 = [⁵⁹Fe-Fe(III)EDTA]^- (retention time, 38 min).