
To define this we must quote what is a printable organ, which is an artificially constructed device designed for organ replacement, produced using 3D printing technologies. The primary purpose of this technology is for transplantation avoiding any kind of organ rejection from the human receptor.
Research is on place now over several kind of organs such as the heart, kidney and even liver structures among other major organs. In the case of the heart for example, which is one of the complex ones, there been research to build “organ substructures” such as the heart valves. Some printed organs have already reached clinical implementation are those that include tissue structures such as the bladder and vascular structures, for example urine tubes.

3D printing allows organ reconstruction based on layers from a particular organ structure to form a cell scaffold, then is followed by a process of “cell seeding” where those are pipetted directly onto the scaffold structure. Other experimental processes integrate cells into the printable material, instead of performing seeding afterwards.

Conventional inkjet printers with several modifications have been used to produce 3D biological tissue, where the printer cartridges are filled with a living cells fluid combined with a smart gel to provide the organ structure.
Alternating patterns of the smart gel and living cells are printed using a standard print nozzle, with cells eventually fusing together to form tissue. When completed, the gel is cooled and washed away, leaving behind only live cells.
Organ printing has been considered as the “final solution” for the global shortage of donor organ transplantation, where the printed organs come from the recipient own cells avoiding time to wait for a donor or organ rejection from the recipient. So far, organs that have been successfully printed and implemented in a clinical setting are flat arranged such as skin, vascular tissue such as blood vessels or hollow such as the bladder.
Materials for 3D printing usually consist of alginate or fibrin polymers that have been integrated with cellular adhesion molecules, which support the physical attachment of cells. Such polymers are specifically designed to maintain structural stability and be receptive to cellular integration. The term “bioink” has been used as a broad classification of materials that are compatible with 3D bioprinting.
3D organ printing is considered as the next big thing that could revolutionize health care, not only for organ transplantation but also for the potential to heal, fight several diseases and improve human lifespan overall.