Fig. 4. (a) Representative images obtained by the fluoresce microscopy, recorded every 5 minutes after dropping the suspension of three E. coli strains. (b) Time-dependent active cell ratio of the hydrophobic nano-pillar array substrate dependent on the strains. Gray circles, red triangles, and blue squares represent the strain RP437 (WT), RP437 fliC (absence of flagella), and RP6894 (presence of flagella but deficit of motility), respectively. Each data shows the average (N = 3) with error bars.
