Advances in bioprinting with a focus on self-healing hydrogels bio-inks for soft tissue regeneration: Innovations, applications, and future perspectives

The field of soft tissue regeneration is undergoing a transformative development thanks to advances in self- healing hydrogel-based bio-inks for 3D bioprinting. Bio-inks play a central role in 3D bioprinting as they facilitate the transfer of cells and the creation of supporting scaffolds. The emergence of self-healing hydrogels represents a promising breakthrough. These hydrogels have the unique ability to repair damage on their own, improving their durability and extending their functional lifespan. Their stability in terms of rheological properties and crosslinking after printing is crucial for successful 3D bioprinting results. Soft tissue injuries are a global clinical concern with limited therapeutic options, highlighting the urgent need for regenerative therapies. Self-healing hydrogel-based bio-inks offer a promising solution to this challenge. They combine biomimetic properties that mimic the extracellular matrix with exceptional rheological stability, making them ideal as bioinks. Ongoing research is focused on optimizing these advanced bio-inks to further improve their performance and expand their potential applications. The paradigm shift associated with self-healing hydrogels signifies a new era in regenerative medicine and gives hope for better therapeutic outcomes for patients suffering from soft tissue injuries and diseases.This review highlights the transformative potential of self-healing hydrogels for 3D bioprinting for soft tissue regeneration. It discusses their specific applications, including cartilage, nerve, skin and cardiac tissue regeneration, and highlights the significant advances that have been made in these areas. Challenges such as printability, gelation and the influence of cellular integration on the properties of bio-inks have posed significant hurdles, which are also discussed.