A. Organ distribution pattern of collagen-I-AuNPs. APC signals were higher in the liver, spleen, and stenotic kidney than in other organs, 2, 4, and 24 hours after injection of APC-collagen-I-AuNPs. B. AuNPs fluorescence (stenotic/contralateral ratio) was significantly correlated with hydroxyproline levels in the stenotic kidneys. C-D. MDCT images showed that the stenotic kidney was smaller and brighter than the contralateral kidney 2hrs after injection of Co-I-AuNPs (C), but not of unconjugated AuNPs (D).