Jsm 6390lv scanning electron

The samples of F1, F2, and F3 scaffolds were metalized with a thin layer of gold by sputtering, with an exposure time of 3 min at 20 mA. The analyses were performed by a Jeol JSM-6390LV scanning electron microscope (Peabody, MA, USA), using an acceleration voltage of 5 kV and spot size of 60.

The samples were prepared in glass vials. The peptide powder was dissolved in dichloromethane, vortex-mixed and diluted with n-heptane at a final concentration of 1 mM. For SEM observation, the samples were dried onto glass slides and sputter-coated with 15 nm thick gold (Baltec SCD 050). To evaluate the nature of the self-assembled elongated structures (hollow or not) a fixation and critical point drying procedure was additionally followed. The samples were fixed in a buffer (2% glutaraldehyde and 2% paraformaldehyde in 0.1 M sodium cacodylate) at pH 7.4 for half an hour at 4 °C, washed twice with the above-mentioned buffer, post fixed in 1% aqueous OsO₄ for 30 min at 4 °C, and rinsed again as above. After fixation, the samples were dehydrated through a graded ethanol series, 30–50–70–90–100% at 4 °C, followed by dry alcohol at room temperature. Dehydrated samples were critical point dried (Baltec CPD 030) and mounted on stubs prior to sputter coating with 15 nm thick gold (Baltec SCD 050). Observation was carried out using a JEOL JSM-6390LV scanning electron microscope at 15 kV operating voltage.