The potential of 3D bioprinting has been further expanded thanks to the work of engineers at the University of New South Wales (UNSW), who have developed a flexible robotic arm capable of printing directly on organs and tissues inside the human body.
In recent years, using 3D printing The technology to create biomaterials incorporating living cells (bioinks) and drugs has emerged to treat a range of conditions by creating, for example, cardiac or gastrointestinal patches.
Currently, bioprinting is mainly used for research and development of new drugs. This requires the use of large 3D printers to create constructs that are surgically implanted into the body, which carries its own risks, including tissue damage and the risk of infection. Since biomaterials are generally soft and fragile structures, they can be damaged by manual handling during the implantation process.
Another common challenge with using externally created 3D constructs is that there can be a mismatch between the construct and the tissue surface on which it is implanted. The implantation of biomaterials directly on target tissues offers a promising solution.
UNSW engineers have developed a miniature, flexible soft robotic arm that can be inserted into the body like an endoscope and deliver biomaterials directly to the surface of organs and tissues.
The proof-of-concept device, called F3DB, is externally controlled and includes a long, flexible robotic arm, at the end of which is a highly maneuverable pivoting head that “prints” bioink through a multi-directional miniature nozzle.
“Existing 3D bioprinting techniques require the biomaterials to be made outside the body, and implanting them into a person would typically require extensive open surgery, which increases the risk of infection,” he said. Dr Thanh Ngo Do, corresponding author of the study.
“Our flexible 3D bioprinter means that biomaterials can be directly introduced into target tissue or organs with a minimally invasive approach,” Do said. “Our prototype is able to 3D print multi-layered biomaterials of various sizes and shapes through confined and hard-to-reach areas, thanks to its flexible body.”
Once the F3DB has finished printing in one area, it can be directed to another location to start the process over. This means that the device can be used to print biomaterials over large areas, including the entire surface of organs such as the colon, stomach, heart and bladder, which cannot be done with current bioprinting devices.
Engineers tested F3DB outside the body on both flat and curved surfaces, including inside an artificial colon and on the surface of a pig kidney, using chocolate, composite gel and biomaterials to accurately print different shapes.
Importantly, they found that the cells were unaffected by the printing process, and after printing, the majority of the cells were still alive.
In addition to imprinting biomaterials, the device functions like an ordinary endoscopic device, cleaning structures with jets of water, marking lesions and dissecting tissue.
“Compared to existing endoscopic surgical tools, the developed F3DB was designed as an all-in-one endoscopic tool that avoids the use of interchangeable tools that are normally associated with longer procedure times and risks of infection,” said Mai Thanh Thai, lead author. of the study.
Currently, there are no commercially available devices that can print on internal tissues and organs. The team behind the F3DB says that with further development, the device should be ready for use by medical professionals within five to seven years.
The study was published in the journal Advanced sciences.