Fig. 4

In vitro antibacterial property of AA hydrogels. a Schematic illustration of antibacterial procedure. Fluorescence intensity of SOSG after adding with different concentrations of AD-Ce6/Apt (b) and irradiation with a laser of different power densities (c). d Survival rates of S. aureus after different treatments (***p < 0.001, n = 5). e Macroscopic crystal violet stained images and corresponding absorbance values of S. aureus incubated with AA hydrogels for 48 h and irradiated with a laser (660 nm, 0.6 W cm⁻²) for 5 min (**p < 0.01, n = 5). f Typical photographs and counting results of S. aureus biofilms treated with PBS and AA + Laser groups by the SPM (***p < 0.001, n = 5). g 3D-reconstructions of the live/dead stained biofilms of S. aureus treated with PBS and AA + Laser. h High-resolution SEM images of S. aureus biofilm treated with PBS and AA + Laser