Fig. 5.

Representative CLSM images assessing diffusion of gatifloxacin within dual-species of S. aureus ATCC 25,923 and S. lugdunensis ATCC 700,328 biofilms formed in the presence of chelerythrine. After dual-species biofilms were grown for 24 h supplemented without or with chelerythrine of different concentration, 0.08 mg mL⁻¹ gatifloxacin was added into the medium, respectively. Following 5-h gatifloxacin diffusion, the biofilms were visualized using CLSM (scale bar: 10 μm). Biofilms were stained with SYTO 9 for biofilms (green) and the intrinsic fuorescence of gatifloxacin (blue)