Fig. 1.

Characterization of Prussian blue nanocubes (PBNCs) and labeled stem cells. (A, B) Transmission electron microscopy (TEM) of dextran-coated PBNCs with an edge length of ∼200 nm. (C) Absorption spectrum of PBNCs, measured by UV–vis spectrophotometry, showed a peak optical absorption at 734 nm wavelength. Histology of eosin-stained adipose-derived mesenchymal stem cells (MSCs) confirmed successful cell labeling with PBNCs (D, E). Naïve MSCs (D) and MSCs incubated with PBNCs at 2 OD (E) at 40x magnification. PBNCs are blue in color and are indicated by black arrows. Proceeding studies were conducted with PBNCs at a concentration of 1 OD.