title: Rapid diffusion of fluorescent tracers into Staphylococcus epidermidis biofilms visualized by time lapse microscopy.
abstract: The transient diffusion of fluorescent tracers into biofilm cell clusters of Staphylococcus epidermidis was visualized by time lapse confocal scanning laser microscopy. Rhodamine B diffused into the center of cell clusters that were 200 to 600 microm in diameter within a few minutes. The apparent effective diffusion coefficient calculated from these data averaged 3.7 x 10(-7) cm(2) s(-1) or 11% of the value in pure water. Fluorescein diffused into biofilm more rapidly, with a diffusion coefficient that averaged 1.6 x 10(-6) cm(2) s(-1), or 32% of the value in water. This study provides direct, visual confirmation that solutes the size of many antibiotics and biocides can diffuse rapidly into biofilms.
authors.affiliation: Center for Biofilm Engineering and Department of Chemical Engineering, Montana State University-Bozeman, Bozeman, MT 59717-3980, USA.
authors.forename: Suriani Abdul
authors.initials: SA
authors.lastname: Rani
authors.forename: Betsey
authors.initials: B
authors.lastname: Pitts
authors.forename: Philip S
authors.initials: PS
authors.lastname: Stewart
mesh_terms: D018441:Biofilms; D004058:Diffusion; D019793:Fluorescein; D005456:Fluorescent Dyes / Q000737:chemistry*; D007091:Image Processing, Computer-Assisted; D007700:Kinetics; D018613:Microscopy, Confocal; D012235:Rhodamines; D013212:Staphylococcus epidermidis / Q000737:chemistry*
chemical_list: D005456:Fluorescent Dyes; D012235:Rhodamines; C029773:rhodamine B; D019793:Fluorescein