ERBB2 and neoplasm: To investigate tumor-targeting efficiency and uptake within HER2+ and HER2− xenograft models (Supplementary Fig. 24), 7.3 nm DFO-scFv-PEG-Cy5-C’ dots were radiolabeled with 89Zr and systemically administered to non-tumor-bearing or BT-474 tumor-bearing mice for assessment of biodistribution, radiostability, whole-body clearance (Supplementary Figs. 25-27; Supplementary Table 3; Supplementary Discussion, Section 2.7) and in vivo HER2-targeted uptake.