Modified Polysaccharides: Potential Biomaterials for Bioprinting.

Polysaccharides have emerged as promising biomaterials for 3D bioprinting due to their inherent biocompatibility, biodegradability, and structural diversity. However, their limited mechanical strength, insufficient bioactivity, and suboptimal printability hinder their direct application in fabricating complex tissue constructs. This review systematically summarizes universal modification strategies to address these challenges by tailoring polysaccharides' physicochemical and biological properties. We first analyse the fundamental requirements of bioprinting materials, emphasising on the critical role of shear-thinning behaviours, post-printing structural fidelity, and cell-instructive functions. Subsequently, we highlight the advantages and limitations of representative polysaccharides, including chitosan, alginate, and hyaluronic acid. Chemical functionalisation, physical reinforcement, and biological hybridisation are proposed as versatile approaches to synergistically enhance printability, mechanical robustness, and bioactivity to tackle the limitations. Furthermore, dynamic crosslinking mechanisms enabling self-healing and stimuli-responsive behaviours are discussed as emerging solutions for constructing biomimetic architectures. Finally, we outline future directions in balancing material processability with cellular viability and scaling up modified polysaccharides for clinical translation. This review aims to provide a design blueprint for engineering polysaccharide-based bioinks toward next-generation regenerative medicine.