*3.7. Morphological Analysis*

The morphology of the blue shark skin colalgens, PSC and ASC was captured using a field emission scanning electron microscope (FE-SEM S-3400 N, Hitachi, Tokyo, Japan) operated at 5 kV. The samples were sputter-coated with gold to produce 10 nm thin layer and moved to the SEM chamber for image capturing at 20 kV voltage.
