Modification of collagen with a natural derived cross-linker, alginate dialdehyde.

The interaction between collagen and a natural derived cross-linker alginate dialdehyde (ADA) was investigated. Fourier transform infrared (FTIR) spectroscopy and the circular dichroism (CD) measurements indicate that the structure integrity of collagen is still maintained after the ADA treatment, while the differential scanning calorimetry (DSC) study suggests that ADA could promote collagen-ADA membrane's thermostability compared to pure collagen. And the atomic force microscopy (AFM) of cross-linked collagen reveals a denser network structure. Besides, the water contact angle test indicates that the hydrophilic property of collagen-ADA membrane is promoted, which is favorable for cell's attachment and proliferation. Meanwhile, the cytocompatibility results imply that not only no extra cytotoxicity is introduced into the collagen-ADA membrane after ADA treatment, but also collagen-ADA membrane facilitates cell's proliferation when the content of ADA is less than 20%. In conclusion, our study reveals that ADA stabilizes collagen as a cross-linker and preserves its triple helical structure.