Introduction to DISP
Caltech researchers have developed a groundbreaking 3D printing technique called Deep Tissue In Vivo Sound Printing (DISP). This innovative method uses sound waves to print materials deep within living tissue, overcoming the limitations of previous techniques that relied on infrared light. The DISP technology has the potential to revolutionize medical treatments and therapies.
The Origin of a Novel Idea
Gao and his colleagues turned to ultrasound, a platform that is widely used in biomedicine for deep tissue penetration. But they needed a way to trigger crosslinking, or binding of monomers, at a specific location and only when desired.
They came up with a novel approach: Combine ultrasound with low-temperature sensitive liposomes. Such liposomes, spherical cell-like vesicles with protective fat layers, are often used for drug delivery. In the new work, the scientists loaded the liposomes with a crosslinking agent and embedded them in a polymer solution containing the monomers of the polymer they wanted to print, an imaging contrast agent that would reveal when the crosslinking had occurred, and the cargo they hoped to deliver a therapeutic drug, for example. Additional components can be included, such as cells and conductive materials like carbon nanotubes or silver. The composite bioink was then injected directly into the body.
/*The Development of DISP*/
The DISP project was initiated at Caltech, with a team of researchers working together to develop a method that could print materials within living tissue. The team, led by experts in biomedical engineering and materials science, began exploring the use of sound waves to trigger polymerization. After extensive research and experimentation, they successfully developed the DISP technique.
Early 3D printing ideas failed due to technological limitations, including slow printing speeds, limited materials, and the high cost of equipment and materials. Additionally, the perception of 3D printed items as lacking in quality or aesthetics contributed to a lack of consumer interest.
/*How DISP Works*/
The DISP process involves injecting a composite bioink containing temperature sensitive liposomes loaded with a crosslinking agent. When focused ultrasound raises the temperature of a targeted area by approximately /*5 degrees Celsius*/, the liposomes release their payload, initiating localized polymerization. This allows for the creation of complex shapes and structures, such as /*hydrogel polymers*/, that can be used for various applications.
/*Applications of DISP*/
The DISP technique has shown promise for applications including tissue repair, targeted treatment delivery, and bioelectric monitoring. Researchers have successfully used DISP to print polymer capsules for drug delivery, adhesive polymers for sealing internal wounds, and bioelectric hydrogels for monitoring physiological signs like electrocardiograms. The technology has the potential to improve treatment outcomes and patient care.
/*Future Directions and Potential Impact*/
The researchers are now working to test the DISP technology in larger animal models, with the ultimate goal of evaluating it in humans. With its excellent biocompatibility and versatility, the DISP technique holds great potential for advancing medical treatments and therapies. The team believes that machine learning can further enhance the precision of the technique, potentially enabling autonomous printing within moving organs like the beating heart. As the technology continues to evolve, it may lead to new possibilities for medical interventions and improved patient outcomes.