Adhesive 12 mm carbon tabs

The surface morphologies and characteristics of the outer and inner sides of each extracted membranes were obtained using field emission scanning electron microscope, FESEM, (Philips XL30, UK) with operation voltage of 5 kV, spot size 3. Before examination, membranes were fixed in 3% (w/v) glutaradehyde in 0.1 M cacodylate buffer for 24 h at 4°C. The fixed membranes were then dehydrated in a series of graded ethyl alcohol solutions for 2 min each: 1 × 70%, 1 × 90% and 3 × 100%. Thereafter, the membranes were critical-point dried by immersing in HMDS for 2 min. The dried membranes were attached onto adhesive 12 mm carbon tabs (Agar Scientific, Stansted, UK) which were pre-mounted onto 0.5 aluminium spectrum stubs (Agar Scientific, UK) before being sputter-coated with gold/palladium (Polaron E500, Quorum Technology, UK). Morphologies of the membranes were analysed at magnification of ×500 and ×2000. In addition, the elemental composition of the extracted membranes were analysed by FESEM with energy dispersive X-ray (EDX) attachment operating at 15 kV, spot size 5.

Collagen scaffold samples were mounted on specimen stubs fitted with adhesive carbon pads, sputter‐coated with carbon and examined using a Zeiss Evo50 (Oxford Instruments, Cambridge, UK) scanning electron microscope, with micrographs obtained at an acceleration voltage of 20 kV. Point EDS spectra were acquired using and Oxford Instruments x‐act EDS detector running INCA software. Silk samples were fixed to adhesive 12 mm carbon tabs (Agar Scientific, Stansted, UK) pre‐mounted onto 0.5 aluminium spectrum stubs (Agar Scientific, UK), and imaged using a field emission scanning electron microscope, (FE)SEM, (Zeiss, EVO HD, Jena, Germany) with operation voltage of 5 kV. Samples on the stubs were sputter‐coated with 95% gold and 5% palladium (Polaron E500, Quorum Technology, UK) and imaged at magnifications of x500 and X1K.