Synthesis of N-succinimidyl 4-[76Br]bromobenzoate and its use in conjugation labelling of macromolecules

Abstract

The 76Br radiobromination of proteins and modified oligonucleotides by the use of N-succinimidyl 4-[76Br]bromobenzoate are described. The labelled N-succinimidyl bromobenzoate was synthesised from the corresponding trimethyltin compound, N-succinimidyl 4-trimethylstannylbenzoate, in 45-60% isolated radio-chemical yield with a specific radioactivity of 20-200 GBq μmol-1. The use of N-succinimidyl 4-[76Br]bromobenzoate in conjugation with the proteins human serum albumin and chromogranin and with 5′-hexylamino-modified oligodeoxy-nucleotides (ODN) and its phosphorothioate analogues (S-ODN), is described. The oligonucleotide sequence chosen for this work is an antisense sequence for the m-RNA encoding for chromogranin in rat.