Table 1.
The electrospinning process parameters used to produce random- and aligned nanofiber scaffolds.
Fig 1.
SEM images of A) random- and B) aligned PCL nanofiber scaffolds. The histograms display a typical skewed right distribution of fiber diameters for both C) random- and D) aligned scaffolds. The electrospun PCL fibers had similar distribution with median diameters around 750 nm. The random and aligned fiber structures show distinct differences regarding fiber morphology.
Fig 2.
The alignment of individual fibers in each scaffold.
The alignment was calculated from 600 fibers per scaffold type and shows a clear difference in overall orientation.
Table 2.
Results from characterization of both nanofiber scaffold types.
Fig 3.
Resulting static water contact angles for the two types of PCL scaffolds.
The angle was measured both parallel- and perpendicular to the aligned fibers to exclude any possible discrepancies.
Fig 4.
The design of the different parts comprising the custom cell stopper inserts.
A) The main part of the insert onto which the scaffold is mounted. B) The toothed ring holding the scaffold in place. C) A removable part with four 1.5 mm pillars acting as cell stoppers. D) All parts assembled into the final insert design. E) The final device as printed in PLA.
Fig 5.
Stainings for nuclei (blue) and actin filaments (red).
A) flat- B) random fiber- C) aligned fiber surfaces. Cells have formed confluent monolayers on all surfaces, and cellular morphologies are thus difficult to analyze. Scale bar = 20 μm.
Fig 6.
A) Cell nuclei size differs significantly between cells cultured on different substrates. B) The aspect ratio of the nuclei is however unaffected by the surface and displays a slight elongation on all topographies. C) The orientation of the nuclei long axes shows a clear trend to orient along the aligned nanofibers, which is not displayed on the other topographies.
Fig 7.
A) To visualize the wound closing process, nuclei stainings (bisBenzimide) were used. B) The cell free area of each wound was measured at the different time points. C) Additionally, the aspect ratio i.e. shape of the wound areas was calculated for each time point and wounds on aligned nanofiber scaffolds appeared to adopt an increasingly elliptical shape over time.
Fig 8.
The percentage of reduced alamarBlue reagent has visibly increased between 48- and 96 h on all topographies. This is to be expected as cells are given serum to keep proliferating throughout the experiment duration. The extent to which they reduce the reagent differs minimally at both time points.