Hydrogels as bioactive scaffolds in biomedical engineering

Hydrogels have emerged as promising biomaterials in tissue engineering and regenerative medicine due to their high water content, biocompatibility, and structural similarity to the extracellular matrix (ECM). This article reviews the design principles and key physicochemical properties of bioactive hydrogels—such as stiffness, porosity, degradation rate, and biochemical functionalization—and their role in modulating stem cell behavior and guiding tissue regeneration. Special attention is given to the influence of hydrogel mechanics on mechanotransduction, strategies for controlled drug and growth factor delivery, and surface functionalization to enhance cell adhesion and lineage-specific differentiation. Recent advances in dynamic, cell-responsive, and degradable hydrogels are highlighted as crucial developments for creating personalized and clinically relevant scaffolds.