Carbon tabbed sem stubs

Scanning electron microscopy (SEM) was used to obtain high magnification images of the fibre scaffolds. Scaffolds were mounted on carbon-tabbed SEM stubs (Agar Scientific Ltd., Stansted, UK) and AuPd sputter-coated for an even coverage. Scaffolds were imaged using a FEI Quanta 250 FEG SEM operating at high vacuum with 5 kV electron beam.
Fibre diameters were measured by analysing the SEM images using ImageJ software (v.1.53c, National Institutes of Health, Bethesda, MD, USA). This was achieved by using the line draw tool and the scale bar of each image to initially set the scale. Measured diameters were statistically analysed using GraphPad Prism v9 (San Diego, CA, USA). Fibre diameters for each group (N = 3; n = 900) were not normally distributed and were subsequently analysed using a Kruskal–Wallis test with Dunn’s multiple comparisons test. Data are presented as the median and interquartile range.

Bovine tissue strips were imaged using scanning electron microscopy (SEM) to observe any architectural damage caused to the dCELL tissues’ structural matrix following decellularization compared to untreated cellular BTM (n = 3). Bovine tissue strips were fixed in 2.5% v/v Glutaraldehyde (TAAB Laboratories Equipment Ltd, Reading, UK) for 24 h at 4 °C. The strips were dehydrated in ascending concentrations of Ethanol (50–100% v/v; (Decon Laboratories Inc., King of Prussia, PA, USA)), critical point dried with Hexamethyldisilazane (HMDS; Sigma-Aldrich, Gillingham, UK) and mounted onto carbon-tabbed SEM stubs (Agar Scientific Ltd., Essex, UK). Mounted strips were Gold/Palladium (AuPd) sputter-coated to increase electrical conductivity and imaged using a HITACHI TM4000 Plus tabletop SEM at high vacuum with a 15 kV electron beam.

Scanning electron microscopy (SEM) was used to obtain high-magnification images of fabricated PCL- and cryo-PCL-electrospun scaffolds. Scaffolds were mounted on carbon-tabbed SEM stubs (Agar Scientific Ltd., Stansted, UK) and gold/palladium (AuPd) sputter-coated (Quorum 1050T S, Quorum Technologies, East Sussex, UK) to increase electrical conductivity. Scaffolds were imaged using a HITACHI TM4000 Plus tabletop SEM at high vacuum with 15 kV electron beam. Two distinct areas of each fiber sheet were imaged per experimental repeat.
Fiber diameters were measured from SEM images using Fiji ImageJ software (v.2.0.0/1.53c, National Institutes of Health, Bethesda, MD, USA) (n = 100). This was achieved by using the scale bar of each image to initially set the scale followed by the line draw tool. Fiber diameters were statistically analyzed using GraphPad Prism v9.1.0 (San Diego, CA, USA). The data were not normally distributed (Shapiro–Wilks normality test) and were subsequently analyzed using a two-tailed Mann–Whitney test. The data were presented as median and interquartile (IQR) range.