Biomaterial scaffolds are used to aid in regeneration of tissue for volumetric muscle loss (VML) where natural regeneration fails. Fibrin microthreads are beneficial due to their mechanical properties, uniaxial cell alignment, and low cytotoxicity. We designed a composite system of a microthread bundle coated with a hydrogel to meet the unmet need of delivering two factors in different time domains to mimic natural healing and assist the regeneration process. Release from the microthreads and hydrogels was quantified with a protein assay and microthread release was validated semi-qualitatively with fluorescence microscopy. Results demonstrated that we created a dual factor, multi-phase release system to aid in skeletal muscle regeneration to potentially heal patients with VML injuries
