Researchers at Caltech, UC Los Angeles, and Terasaki Institute for Biomedical Innovation have created a new method to make medical implants inside the body without surgery. This method uses 3D bioprinting, which builds objects layer by layer to create custom medical devices or tissues. Normally, 3D bioprinting needs surgery to place the implants. The new technique, called in vivo bioprinting, prints directly inside the body, making it less invasive.
The researchers invented a system named Deep Tissue In Vivo Sound Printing, or DISP. This system uses focused ultrasound, a technology that sends sound waves to a specific spot, to print biomaterials deep inside the body. They also developed special bioinks, which are liquids made of biopolymers, natural materials safe for the body, and tiny capsules that release a glue-like substance when heated.
The process starts by injecting or using a catheter to deliver bioinks to the target area. A device called a focused ultrasound transducer, guided by a computer plan, heats the area slightly. This heat opens the capsules in the bioinks, releasing the glue to form a solid gel right in the tissue. The gels can carry drugs, conduct electricity, or stick to tissues, and doctors can see them with imaging tools.
The researchers have described the methods and results of this study in a paper published in Science. See also a related Perspective.
Testing the new method
The researchers tested DISP in animals. They printed drug-loaded gels near cancerous areas in a mouse bladder and deep in rabbit muscle tissue. The tests showed the method can deliver drugs, help tissues grow, or support bioelectronics. The researchers also checked for safety. The tests found no tissue damage or swelling, and the body removed leftover bioink within a week.
This method could change how doctors treat patients by creating implants exactly where needed without cutting the body open. The gels can release medicine slowly or help repair tissues. However, the researchers say more work is necessary before using this in hospitals. Scientiss need to study how the printing process affects the gels’ structure and performance. Careful testing will ensure the technology works well for real medical treatments in the future.