The use of charged linkers in attaching radiohalogens to tumor-seeking biomolecules may improve intracellular retention of the radioactive label after internalization and degradation of targeting proteins. Derivatives of polyhedral boron clusters, such as closo-dodecaborate (2-) anion, might be possible charged linkers. In this study, a bifunctional derivative of closo-dodecaborate, (4-isothiocyanatobenzyl-ammonio)-undecahydro-closo- dodecaborate (DABI) was labeled with positron-emitting nuclide 76Br (T = 16.2 h) and coupled to anti-HER2/neu humanized antibody Trastuzumab. The overall labeling yield at optimized conditions was 80.7 ± 0.6%. The label was proven to be stable in vitro in physiological and a set of denaturing conditions. The labeled antibody retained its capacity to bind to HER-2/neu antigen expressing cells. The results of the study demonstrated feasibility for using derivatives of closo-dodecaborate in indirect labeling of antibodies for radioimmunoPET.
- (4 isothiocyanatobenzyl- ammonio)-bromo-decahydro-closo-dodecaborate
- Indirect radiobromination
- Monoclonal antibody
ASJC Scopus subject areas
- Molecular Medicine
- Radiology Nuclear Medicine and imaging
- Cancer Research