Abstract A number of different thiol protective groups have been synthesized and attached to mercaptoacetyltriglycine (MAG3) ligand. The newly made MAG3 analogues were labelled with 99m Tc by direct labelling under alkaline condition and by stannous tartrate exchange labelling method. In the latter method, the amount of the ligand, reaction temperature and pH varied and their effects on the labelling efficiencies were studied.
