Fig. 2.

Fabrication of CMs with various concentrations of chitosan solutions and electric potential for electrospinning at 2.0 ml/h of a constant feeding rate. a SEM of the CMs after solidification and the insets in the SEM image are the optical microscopic images of CMs before lyophilization. b Average diameters of CMs based on an image analysis of the SEM images. The average sizes were plotted against the concentrations of chitosan and the electric potentials (n = 10). All scale bars in the images are 500 μm. Asterisks average size of CMs was not measured due to irregular shapes of the CMs