Fig. 3
From: Alkylated EDTA potentiates antibacterial photodynamic activity of protoporphyrin
S. aureus biofilm eradication assay. a Mature S. aureus biofilms were treated with the combinations of PpIX (17.77 μM) and EDTA or C14-EDTA (0.05 mM, 0.1 mM, or 0.5 mM), followed by illumination for 1 h or 2 h; the remaining biofilms were subjected to the crystal violet assay to determine the viability. b–c 3D reconstruction b and cross-sections c of S. aureus biofilms by CLSM imaging; the biofilms were treated with 17.77 μM of PpIX and 0.1 mM of EDTA or C14-EDTA and then illuminated for the indicated durations; the biofilms were then stained using the Live/Dead BacLight™ Bacterial Viability Kit and observed using CLSM; Green: Syto9, Red: PI, Blue: PpIX. d The biofilm thickness quantified by Image J in c. Data are presented as mean ± SD (n = 3). ****P < 0.0001, ***P < 0.001, **P < 0.01