Incorporation of chitin nanocrystals into fish collagen-gelatin bio-scaffolds: Enhancing functional properties and...

The rising demand for sustainable, biocompatible biomaterials has increased interest in marine-derived scaffolds for tissue engineering. This study reports the extraction of pepsin-soluble collagen (PSC; 18.01 ± 0.53 %) and gelatin (11.95 ± 0.24 %) from deep-sea fish (Kathetostoma sp.) skin, and the incorporation of chitin nanocrystals (ChNCs) from deep-sea shrimp shell waste to fabricate composite scaffolds. ChNCs exhibited needle-like morphology (201.49 ± 20.55 nm length, 26.55 ± 12.33 nm width) and high purity. The resulting hybrid scaffolds demonstrated enhanced tensile strength (up to 5.09 MPa), reduced shrinkage, increased water-binding capacity, and controlled degradation (~4 days), supporting extracellular matrix remodeling. FTIR and SEM analyses confirmed uniform ChNC integration. Antioxidant assays showed improved DPPH (up to 59.8 %) and FRAP activity with ChNC incorporation. In vitro cytocompatibility tests using HEK293 cells confirmed >90 % viability, indicating non-toxicity. These findings demonstrate the potential of marine collagen-gelatin/ChNC scaffolds as porous, biodegradable biomaterials for soft tissue engineering, while promoting circular bioeconomy through valorization of deep-sea by-products.