Additional file 1 of Aligned nanofibrous collagen membranes from fish swim bladder as a tough and acid-resistant suture for pH-regulated stomach perforation and tendon rupture

Additional file 1: Supplementary Fig. S1. PGA with highly complex structure under SEM. Supplementary Fig. S2. Two other crosslinking methods. Supplementary Fig. S3. The detailed process of fabricating DCDS suture with standardization. Supplementary Fig. S4. The tensile strength of double-layers swim bladder with and without crosslinking