Figure 4.

Tissue cryosection fluorescence microscopy showing distribution of photoluminescence from bio CFQD® nanoparticles in the rat liver. Blue corresponds to lower intensity and white to highest, and the same intensity scale was used throughout for direct comparison. QDs were injected at 12.5 mg/kg intravenously and images were obtained at various time intervals post-injection. (A) 5 min; (B) 1 h; (C) 4 h; (D) 24 h; (E) 48 h; (F) 72 h; (G) 5 days; (H) 10 days: (I) 20 days: (J) 40 days: (K) control - without QDs injection. (L) Time-course of integrated mean photoluminescence intensity of bio CFQD® nanoparticles in the cryosections of rat liver using fluorescence microscopy with control baseline level subtracted.