Advances of mussel-inspired hydrogels for Bone/Cartilage regeneration

The clinical injury of bone and cartilage tissue is complex and specific, posing a significant threat to human health as traditional regenerative therapies (including autograft and allograft etc.) often result in side effects and poor prognosis. In this regard, hydrogel materials with unique three-dimensional structure, high water content, and biomimetic characteristics have emerged as promising candidates for supporting stem cells in achieving clinical bone/cartilage regeneration. However, the limited functionality of conventional hydrogels due to their single composition necessitates modification or enhancement for gaining specific properties. Mussel-inspired chemistry offers strong modification potential to hydrogels while improving various biological performances, making them widely applicable in bone/cartilage regeneration. In this review, we firstly provide a brief overview of common methods for designing hydrogels that promote bone/cartilage regeneration. Subsequently, typical functionalization approaches employed in mussel-inspired hydrogels including enhancing adhesion ability, improving antioxidant activity, augmenting loading capability along with the corresponding methodologies used to achieve these functionalizations were summarized. Finally, the challenges faced by mussel-inspired hydrogels were highlighted and potential directions for future research endeavors were proposed, aiming at providing novel ideas and inspiration to researchers.