Figure 6. Inhibition of silver-resistant bacteria by AgNP/NSP.

The cytotoxicity of silver nitrate and AgNP/NSP on E. coli J53 (A) or J53/pMG101 (B) were tested by colony growth on agar. Silver concentrations for 0.01, 0.02, 0.05 and 0.1 wt% AgNP/NSP were 64.9 µM, 129.8 µM, 324.5 µM and 648.9 µM, respectively. At 4 hr incubation with the nanomaterials, the ratios of fluorescent PI/Syto9 cells (C), DCF⁺ cells (D) and 2-NDBG⁺ cells (E) were determined by FACS analysis. The content of intracellular ATP was reflected by luciferase activity in the treated cells (F). The data represent triplicate (A, B) or duplicate experimental results (C–F). *, p-values<0.05, Student's t-test.