Fig. 2: Mechanical properties of the cell.
a Mechanical characterization of the cell (in red) and nanoseeds (in blue) by nanoindentation. The apparent breakpoint shows the fracture strength of the cell. The inset shows the SEM image of the fractured cell under 4-mN load. Scale bar: 10 μm. b Variation of the scratch depth as a function of the indenter displacement under 0.4-mN load, in which the red line refers to the cellular coating and the blue line refers to the nanoseed-alone coating. As shown in the inset images, the cellular coating was kept almost intact whereas a deep groove was created on the nanoseed-alone coating by the indenter. Scale bar: 10 μm. c Hardness and elastic modulus of different coatings. The errors represent the standard deviations from at least three independent experiments. d, e SEM images of the cellular coating (d) and zoom-in view of the released nanoseeds (e) after micro-scratching under a load of 4 mN. f, Comparison of roughness change of different coatings after abrasion. The errors represent the standard deviations from at least three independent experiments.
