Fig 3.

Surface coverage as a function of time on uncoated silicone rubber and polymer brush-coated silicone rubber by biofilms grown in the absence or presence of various concentrations of gentamicin (open squares, no antibiotic; open triangles, 0.5 μg/ml gentamicin; gray triangles, 5 μg/ml gentamicin; black triangles, 50 μg/ml gentamicin) and coverage by live organisms after 20 h of growth (green bars). Gentamicin was introduced after 4 h of growth. Error bars represent standard deviations of two separate experiments. Panels: a, S. aureus ATCC 12600; b, S. epidermidis 138; c, P. aeruginosa #3. An asterisk indicates a significant difference (P < 0.05) between uncoated silicone rubber and polymer brush-coated silicone rubber in surface coverage by biofilm after 20 h of growth. The symbol # indicates a significant difference (P < 0.05) between the numbers of live bacteria in 20-h-old biofilms on silicone rubber and polymer brush-coated silicone rubber.