Fig. 2
Wetting properties of the topographies used for the study. (a) WCAs measured on sPDMS, hPDMS, and PMMA substrates with a wide variety of topographies (nano-, hierarchical (LAR + ME), LAR and HAR microtopographies). Note the difference in the WCA of the gratings according to their orientation (shown by red box, O1 and O2). (b) WCAs measured in flat and ME nanopatterned substrates fabricated on hPDMS and PMMA polymers before and after 5 h incubation in a protein-enriched medium (LB broth). (c) WCAs for hPDMS either flat or topographed (ME) at 1 h, 24 h and 72 h after oxygen plasma treatment. Measurements were plotted as the WCA mean ± SE. One-way ANOVA analysis shows statistical significance by **** p-value < 0.0001. Dashed lines show the contact angle intervals that determine hydrophilicity (θ < 90˚), hydrophobicity (90˚< θ < 150˚) and superhydrophobicity (150˚ < θ). Representative water droplets are shown above data columns.
