Fig. 1

Variation of the scaling factor k_b = (WB_h/WB_a)^α as a function of the animal body mass. The figure shows how the scaling factor (WB_h/WB_a)^α, applied in M3 and M4, varies according to the animal body mass, for a mass of 73 kg (human adult male reference phantom). Four curves are presented, considering the reference α = 0.25 (green line) [19, 20, 23], the α_new = 0.17 (orange line) obtained experimentally for [⁶⁸Ga]NODAGA-RGDyK, as well as the lowest and the highest organ α′ values, i.e. α′ = − 0.14 (magenta line) and α′ = 0.39 (blue line), found in this study for liver and red marrow, respectively. The shadow areas represent the uncertainties around the calculation of α_new and of α’ extremes (see Table 4). The circles represent the scaling factors corresponding to the masses of the murine, rat and canine models implemented in OLINDA/EXM 2.0. In the case of a 25 g mouse, the scaling factors are 7.35 and 3.88 for α = 0.25 and α = 0.17, respectively. Images of animals and humans are copyright-free images taken from the Internet (dreamstime.com)