In vitro and in vivo studies of Tc-99m IgG: A comparison between three labeling methods

Polyclonal immunoglobulin IgG was labeled using three different methods: a direct method via 2-mercaptoethanol, an indirect one, in which a chelating group was covalently attached to the protein and the Tc-99m added as a gluc oheptonate complex and a photoactivation method. The properties of Tc-99m p olyclonal antibody labeled by three different methods were assessed by in v itro and in vivo studies. The ratio between inflamed thigh to normal thigh was similar and independent of the method of labeling.