Scanning electron microscopy
Morphology of cross-sections of the scaffolds and both surfaces were examined using scanning electron microscopy (SEM) with the Hitachi TM1000 apparatus. Before the examination, samples of scaffolds were immersed in ethanol and then broken in liquid nitrogen. After drying, samples were covered with a 7–10 nm layer of gold using the K550X Sputter Coater. Samples covered with gold were examined at 300x and 1000x magnifications with the use of an acceleration voltage of 15 kV.