Several peptides comprising Arg-Gly-Asp (RGD) domain and macrocyclic chelator were labelled with 68Ga for the imaging of angiogenesis. The analogues varied in peptide constitution, linker and chelator type. The labelling efficiency did not vary with the peptide constitution and linker type, but depended on the chelator type. Four of the compounds containing 2,2',2'',2'''-(1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrayl)tetraacetic acid (DOTA) chelator were labelled at 90 ± 5 °C using conventional or microwave heating reaching 90% of 68Ga incorporation after 5 and 2 min respectively, when the concentration of the precursor was 2.5 mM. The compound having 2,2',2''-(1,4,7-triazonane-1,4,7-triyl)triacetic acid (NOTA) as the chelator could be labelled at room temperature within 5 min using 2.5 mM peptide precursor. Two of the compounds contained a poly(ethylene glycol) (PEG) linker to the chelator.