Fig. 9. (a) Photographs of the antibacterial activities of purified silver nanoparticles with a series of decrement concentration (50–0.0977%) against (a) S. aureus, (b) P. aeruginosa, (c) S. enterica and (d) E. coli. The turbidity of solutions indicates the growth of microorganisms, and a red square indicates the lowest concentration where there is no turbidity. (b) Comparison of the MICs of silver nanoparticles for four Gram-positive and Gram-negative bacteria.
