Figure 4. Specificity of targeting of SKOV-3 xenografts in BALB/C nu/nu mice using ⁶⁸Ga-DOTA-Z_HER2:S1, ⁶⁸Ga-NOTA-Z_HER2:S1 and ⁶⁸Ga-NODAGA-Z_HER2:S1 at 1h after injection.

The total injected radiolabeled peptide dose per mouse was 3 µg (0.42 nmol). The blocked group was subcutaneously pre-injected with an excess amount (1000 µg, 150 nmol) of non-labelled Z_HER2∶342 to saturate binding sites of HER2. Results are expressed as percentage of injected activity per gram of tissue (%IA/g) and presented as mean values for four mice and standard deviations. Uptake of radioactivity was significant lower (p<0.0005) for pre-saturated SKOV-3 tumors.