Engineering of hydrogel materials for 3D printing

The development of advanced biomaterials simultaneously exhibiting proper printability, biomechanical properties, and providing a suitable microenvironment for cells encapsulation still remains the major challenge in 3D printing. Hydrogels are the most commonly explored materials for the fabrication of 3D scaffold for tissue engineering, as they provide a soft and porous matrix able to couple the chemical properties of the surface with the physical properties of the gel. In this work, different hydrogel systems are chemically modified to be printed by stereolithography with improved Z-resolution and also by two-photon lithography. Moreover, a precise chemical design by the introduction of crosslinkable units, having reaction orthogonality, allowed to control the network formation both in time and space and to selectively alter the hydrogel physical properties (e.g. stiffness).