Hydrogel-based bio-inks: Current progress and future directions in 3D printing

Abstract

Hydrogel-based bio-inks have become a cornerstone in the advancement of 3D bioprinting, particularly for tissue engineering applications. This review explores the current progress and future directions in the development of hydrogel-based bio-inks for 3D printing. Hydrogels, with their high water content and biocompatibility, closely mimic the natural extracellular matrix, making them highly suitable for creating tissue scaffolds. Recent advancements include the enhancement of mechanical properties, printability, and bioactivity through the incorporation of nanomaterials and the combination of natural and synthetic polymers. These improvements have led to better structural integrity and functional capabilities of printed scaffolds. The integration of bioactive molecules and growth factors within hydrogel matrices has further promoted cell proliferation and differentiation, and enhancing tissue regeneration. However, challenges such as the need for standardized protocols, improved printing resolution and precision, and the development of bio-inks that can support complex cellular microenvironments are still exiting. Future research is likely to focus on developing multifunctional bio-inks capable of adapting to diverse biological and mechanical needs. This includes stimuli-responsive hydrogels and novel bioprinting techniques like microfluidic-based and laser-assisted printing. Addressing these challenges and exploring new directions will significantly advance the field of tissue engineering and regenerative medicine.