This project aims to develop protocols for photocrosslinking of collagen extracted from rat tail tendons as well as decellularized tissue that will be used for 3D bioprinting. 3D bioprinting enables the creation of in vitro models of various tissues as testbeds for therapeutics, revolutionizing the future of medicine. Goal is to apply already optimized bioprinting protocols in order to obtain 3D structure. This will require further optimization of the parameters for printability using bio-printer. Rheological properties of thermally gelling hydrogels such as collagen and decellularized tissue matrices and photo-cross-linkable hydrogels will be assessed across multiple hydrogel concentrations and compared. Cell viability in 3D printed structures will be accessed.