Researchers at UNSW Sydney have developed a small and flexible soft robotic arm that might be used to 3D print biomaterial directly onto organs inside the body of a patient. 3D bioprinting is a method for fabricating biomedical components using so-called bio-ink to create structures resembling genuine tissue.
Bioprinting is mostly utilized for research reasons, such as tissue engineering and the creation of new medications, and typically necessitates the use of massive 3D printing equipment to create cellular structures outside of the living body.
New research from the UNSW Medical Robotics Lab, led by Dr. Thanh Nho Do and his Ph.D. student, Mai Thanh Thai, in collaboration with other UNSW researchers, including Scientia Professor Nigel Lovell, Dr. Hoang-Phuong Phan, and Associate Professor Jelena Rnjakovic-Kovacina, has been published in Advanced Science.
Their efforts have produced a tiny, flexible 3D bioprinter that can be introduced into the body like an endoscope and deliver multilayered biomaterials directly to the surface of internal organs and tissues. The F3DB proof-of-concept device has a highly maneuverable swivel head that ‘prints’ the bio ink, attached to the end of a long and flexible robotic arm resembling a snake, all of which are externally controllable.
With additional development, and possibly within five to seven years, medical personnel may be able to access difficult-to-reach parts of the body through small skin incisions or natural orifices, according to the research team. The research team tested the gadget in an artificial colon, where it was able to navigate through limited places prior to 3D printing successfully. Dr. Do and his team have tested their gadget in an artificial colon and 3D-printed a variety of materials with varying forms on the surface of a pig’s kidney.
Dr. Do, a Scientia Senior Lecturer at UNSW’s Graduate School of Biomedical Engineering (GSBmE) and Tyree Foundation Institute of Health Engineering, stated, “Existing 3D bioprinting techniques require biomaterials to be made outside the body, and implanting them into a person would usually require large open-field open surgery, which increases infection risks” (IHealthE).
“With the aid of our flexible 3D bioprinter, biomaterials can be delivered directly into the target tissue or organs in a minimally intrusive manner. This method enables the precise restoration of three-dimensional wounds within the body, such as lesions to the gastric wall or damage and disease within the colon.
“Because tofits flexible form, our prototype is able to 3D print multilayered biomaterials of various sizes and shapes through tight and inaccessible places. “Our technique also overcomes important constraints in existing 3D bioprinters, including surface mismatches between 3D printed biomaterials and target tissues/organs and structural damage during manual handling, transferring, and transporting.”
Scientia Professor Nigel Lovell, Head of the GSBmE and Director of the IHealthE, noted, “There are currently no commercially available technologies that can do in situ 3D bioprinting on distant interior tissues/organs.” Several proof-of-concept devices have been presented, but they are significantly more stiff and difficult to utilize within the body’s intricate and limited regions.”
The diameter of the UNSW team’s smallest F3DB prototype is comparable to that of commercial therapeutic endoscopes (about 11-13mm), making it tiny enough to be placed into a human gastrointestinal tract. Yet, according to the researchers, it might be easily scaled down for future medicinal applications.
A three-axis printing head is directly attached to the tip of a soft robotic arm on this device. This printing head, which is comprised of soft artificial muscles that let it to move in three dimensions, functions similarly to traditional desktop 3D printers.
Due to hydraulics, the soft robotic arm can bend and twist and may be constructed in any length desired. Using a variety of elastic tubes and materials, its rigidity may be precisely adjusted.
The printing nozzle can be set to print certain shapes or manually operated for bioprinting that is more intricate or unpredictable. In addition, the team utilized a controller based on machine learning to facilitate the printing process. To further establish the viability of the method, the UNSW team examined the cellular viability of biomaterial printed using their approach.
Tests revealed that the technique had little effect on the cells, with the majority of cells remaining alive after printing. After seven days of growth, four times as many cells were seen one week following printing. The study team also illustrated how the F3DB might potentially be utilized as a multifunctional endoscopic surgical instrument. Endoscopic submucosal dissection, also known as endoscopic submucosal resection, is a surgical procedure used to remove certain malignancies, particularly colorectal cancer (ESD).
Colorectal cancer is the third most common cause of cancer death worldwide, however, early removal of colorectal neoplasia increases the patient’s five-year survival rate by at least 90 percent. The nozzle of the F3DB printing head can be utilized as an electric scalpel to first identify and then remove malignant tumors.
Water can also be directed via the nozzle to simultaneously remove blood and superfluous tissue from the surgical site, while 3D printing biomaterial directly while the robotic arm is still in situ can promote faster recovery. On a pig’s intestine, the ability to do such multi-functional procedures was established, and the results indicate that the F3DB is a good candidate for the future creation of an all-in-one endoscopic surgical instrument.
“Compared to existing endoscopic surgical instruments, the F3DB was created as an all-in-one endoscopic instrument that eliminates the need for interchangeable instruments, which are typically linked with lengthier procedure times and increased infection risks,” stated Mai Thanh Thai.
The technology, which has been given a provisional patent, will undergo in vivo testing on living animals to establish its practical application. In addition, the researchers intend to install additional features, such as an integrated camera and real-time scanning system that would rebuild the 3D tomography of the body’s moving tissue.
