Figure 1. In vitro characterization and safety assessment of 68Ga-HZ20. (A) Schematic illustration of the synthesis of the 68Ga-HZ20 probe. (B) Radiolabeling rate (RLR) of 68Ga-HZ20 at different temperatures. (C) Radiochemical yield of 68Ga-HZ20 at different temperatures (n=3). (D) Stability analysis of68Ga-HZ20 over time in saline and 5% HSA at 37℃ (n=3). (E) HE staining of major organs indicates the safety of radio-tracer (n=5). (F) IHC of ACE2 expression levels in major organs.