Fig. 4

Antibacterial properties of the hydrogel systems. a Representative culture images of bacterial colonies formed by S. aureus (the top row) and E. coli (the bottom row) after exposure to PBS, CMs of Sil-MA, M@M-Sil-MA, Ag-Sil-MA, M@M-Ag-Sil-MA and the relative amounts of the corresponding colonies of S. aureus (b) and E. coli (c) determined by spread plate method. d Representative SEM images of S. aureus and E. coli treated with PBS or different CMs. Yellow spheres indicate S. aureus, and violet rods indicate E. coli. *P < 0.05, **P < 0.01 and ***P < 0.001) (Scale bar: 1 μm)