Recent advances in 3D cryoprinting

3D bioprinting is a fabrication method that involves the layer-by-layer deposition biomaterials and cells. 3D bioprinted scaffolds can be used outside of the body, such as for disease models and drug development, or can be implanted into the body to replace damaged organs and or tissue. Advances in 3D bioprinting will bring this promising technique to the clinic and address the growing shortage of donor organs and tissue. Various types of 3D bioprinting exist, including “3D cryoprinting” or “3D cryobioprinting” which involves depositing biomaterial into a cryogenic environment. Since the introduction of 3D cryoprinting in 2015, this technique has gained popularity as a method of fabricating scaffolds out of soft bioinks that are otherwise difficult to print with. This review discusses recent progress in 3D cryoprinting. First, we discuss the advantages of this fabrication method, including the creation of highly porous scaffolds, protection for cells from environmental stressors during printing, and the ability to print anisotropic tissue in the vertical direction. Additionally, recent work demonstrated that 3D cryoprinting is a streamlined approach to printing and cryo-preserving cell-laden scaffolds for long-term storage. Second, we review various bioinks used for 3D cryoprinting and the crosslinking approaches that have been used with them. Third, we review the various applications of 3D cryoprinting, including the printing of scaffolds for bone, muscle, cartilage, and skin tissue regeneration. Fourth and finally we discuss current limitations in 3D cryoprinting and future trends for this field.