FIGURE 4. In vitro stability of cmAb U36-N-sucDf-⁸⁹Zr and cmAb U36-SMCC-SATA-Df-⁸⁹Zr, monitored by HPLC. Conjugates were incubated for 24 h at 37°C: cmAb U36-N-sucDf-⁸⁹Zr in human serum (A); cmAb U36-SMCC-SATA-Df-⁸⁹Zr in human serum (B); cmAb U36-SMCC-SATA-Df-⁸⁹Zr in HSA, at pH 9 (C); and cmAb U36-SMCC-SATA-Df-⁸⁹Zr in HSA, at pH 9 with an excess of L-cysteine (D). Retention times of IgG and HSA are indicated.