Figure 1.

TEM and element mapping analysis of Bio-SeNPs. The Escherichia coli S17-1-pCT-Zori-csrF strain was cultured until OD₆₀₀ reached 0.8–1.0. Then, the cells were incubated without selenite for 24 h (A,B) and 36 h (C,D) and with selenite (1 mmol/L) for 24 h (E,F) and 36 h (G,H); The Bio-SeNPs were extracted from the cells (I); The HAADF (J) and Se, C, N, O, P and S elemental mapping (K–P) images of Bio-SeNPs were obtained.