Figure 1. (a, b) TEM images of OA-BaYbF₅:2% Er³⁺ nanocubes in chloroform; (c) TEM images of RGD-labelled UCA in water; (d) CT values and (e) images of UCA and Iobitridol with different concentrations; (f) In vivo blood terminal half-life (t_1/2) of UCA-RGD in vivo (n = 3) and (g) Cell viabilities of U87MG and MCF-7 cells incubated with UCA-RGD of different concentrations for 24 h.