A desferrioxamine B squaramide ester for the incorporation of zirconium-89 into antibodies

Abstract

A squaramide ester derivative of desferrioxamine B (H₃DFO) that is compatible with aqueous solvents and does not induce antibody aggregation is used to attach the siderophore to the antibody trastuzumab. The new conjugates were radiolabeled with zirconium-89 to give complexes that are more resistant to ligand exchange when compared to currently used H₃DFO derivatives and result in high quality positron emission tomography images in mouse models of HER2 positive breast cancer.