Biocompatibility and structural insights of seaweed-derived cellulose scaffolds in a subcutaneous implantation model

Sustainable biomaterials are essential for advancing tissue engineering. This study investigates the in vivo biocompatibility and regenerative potential of seaweed cellulose (SC) scaffolds derived from Ulva sp. and Cladophora sp. as connective support matrices. SC scaffolds were fabricated using an optimized decellularization process that preserved their distinct porous (Ulva) and fibrous (Cladophora) architectures. Subcutaneous implantation in Sprague-Dawley rats demonstrated minimal foreign body response and successful integration over an eight-week period. Histological analysis revealed architecture-driven healing dynamics: Ulva sp. scaffolds promoted compartmentalized healing, characterized by distributed vascularized connective tissue, while Cladophora sp. scaffolds supported stratified tissue organization with aligned collagen deposition. Both scaffolds exhibited progressive vascularization and reduced foreign body response, with no adverse inflammatory reactions observed. These findings highlight the potential of SC scaffolds for regenerative applications that require tailored tissue responses, while their renewable, marine- origin underscores their potential as sustainable biomaterials in advanced healthcare solutions.