FIG. 8.

High resolution 3D imaging over a large field of view enables an accurate measurement of traditional surface metrology metrics such as film roughness and maxima. Data from two experiments show results during the initial attachment and colonization phase in the first 24 h of growth (a) and (c) and measurement from a mature biofilm over a longer period of time—172 h (b) and (d). As the biofilm attached and covered the flow cell surface, the surface roughness (a) increased after 16 h. During this time, the maximum thickness (c) of the biofilm increased steadily before stabilizing at a maximum by 24 h. In the longer experiment, roughness (b) and maximum (d) reached stable values after 24 h, though both varied over the remainder of the experiment. The roughness and the maximum were calculated using averaged data from three locations in a single flow cell. Values are a mean of the three locations with standard error bars.