Bioorthogonal chemistry for ⁶⁸Ga radiolabelling of DOTA-containing compounds

Copper-catalysed 'click' chemistry is a highly utilised technique for radiolabelling small molecules and peptides for imaging applications. The usefulness of these reactions falls short, however, when metal catalysis is not a practically viable route; such as when using metal chelates as radioligands. Here, we describe a method for carrying out 'click-type' radiochemistry in the presence of DOTA chelates, by combining ⁶⁸Ga radiolabelling techniques with well-established bioorthogonal reactions, which do not rely upon metal catalysis.