Two-step DNA redox labelling with borane cluster compounds

Abstract

DNA redox labelling finds wide applications in bioanalysis and diagnostics. Boron cluster compounds (BCCs) present a promising alternative to traditionally used tags. This study introduces a novel two-step method for preparing single-stranded (ss) DNA fragments labelled with BCC tags. The method combines Huisgen azide-alkyne cycloaddition with terminal deoxynucleotidyl transferase tailing reactions to create terminally BCC-labelled DNA oligonucleotides. The synthesized BCC-based azides were successfully attached to ethynyl-decorated ssDNA, and the resulting products were characterized using polyacrylamide gel electrophoresis and electrochemical measurements. The electrochemical analysis revealed distinct oxidation peaks corresponding to the BCC moiety, confirming the successful incorporation of BCC tags into the DNA. This approach not only expands the toolkit for DNA redox labelling but also opens new avenues for developing advanced bioanalytical and diagnostic applications.