Figure 5: Small-animal PET and quantification analysis. (a) Small animal PET imaging of tumor-bearing mice at 1 h, 2 h, 4 h, and 24 h after tail vein injection of 110 μCi of 64Cu-DOTA- . Representative decay-corrected coronal PET images were shown on different tumor-bearing animals, including Hep3B, PLC/PRF/5, and PLC/PRF/5 with blocking dose of unlabeled Ac-Cys- . Arrows indicate the location of tumors. (b) Quantification analysis of tumor-to-normal organ ratio in Hep3B and PLC/PRF/5 tumor-bearing mice, respectively, at 1 h, 2 h, 4 h and 24 h after tail vein injection. (c) Quantification analysis of tumor or liver uptake of 64Cu-DOTA- in PLC/PRF/5 tumor models (represented as PLC5 in Figure) and Hep3B tumor models at different time points after injection of the PET probe. (d) Quantification analysis of the probe accumulation in PLC/PRF/5 tumor with (represent as time point B) or without coinjection of unlabeled Ac-Cys- at 1 h, 2 h, 4 h, and 24 h p.i.