Fish collagen-based scaffold containing PLGA microspheres for controlled growth factor delivery in skin tissue engineering

[Display omitted] •A GF release system was consisted of fish Col/Ch/CS scaffold and PLGA MPs.•The release rate could be adjusted by the ratio of collagen to chitosan and the size of MPs.•The released bFGF retained its structure integrity and bioactivity.•The scaffolds/MPs could promote cell proliferation and tissue regeneration.•This scaffold/MP release system has the potential for skin tissue engineering. To design a scaffold controlled release system for skin tissue engineering, fish collagen/chitosan/chondroitin sulfate scaffolds were fabricated by freeze-drying and incorporated with bFGF-loaded PLGA microspheres (MPs). SEM showed that the scaffolds exhibited an interconnected porous structure, and the spherical MPs were uniformly distributed into the scaffolds. The higher swelling and degradation rate of scaffolds/MPs could lead to a higher diffusion rate of MPs from the scaffolds, causing an increase in the protein release. The release rate of proteins could be adjusted by the size of MPs and the ratio of collagen to chitosan of scaffolds. Circular dichroism spectroscopy and MTT of bFGF after release indicated that the released bFGF retained its structural integrity and bioactivity during preparation. Cell proliferation and in vivo evaluation results suggested that the scaffolds/MPs had a good biocompatibility and an ability to promote fibroblast cell proliferation and skin tissue regeneration. These results demonstrated that this scaffold/MP controlled release system has the potential for skin tissue engineering.