Fig. 4

In vivo toxicological studies of SPIONs. Pathological damage in the heart (a) liver (b) spleen (c) lung (d) kidney (e) and brain (f) of normal and SPION-injected rats at 1, 2, 3, 7 and 14 days were detected by histopathological sections and HE staining. g–l Iron content in these organs of normal and SPION-injected rats at 1, 2, 3, 7 and 14 days were detected by ICP-AES measurement. m–r The AST, ALT, ALP, TP, ALB, and Cr levels of normal and SPION-injected rats at 1, 2, 3, 7 and 14 days were determined by serum biochemical analysis. Each experiment was carried out in triplicate. The values are represented as the mean ± SD. Scale bar = 50 µm in panels a-f. *P < 0.05, **P < 0.01