3D printing directly inside the human body
For the first time, researchers in the US have succeeded in printing solid hydrogel structures directly inside the human body. This revolutionary new technique paves the way for new applications in medicine, such as the creation of artificial tissue or organs, or the treatment of diseases or injuries, directly inside the body.
This feat was achieved by a team of researchers led by Professor Wei Gao of the California Institute of Technology (Caltech). It is a fascinating advance in 3D printing, applied to biological processes through the use of sound waves.
The method, called deep tissue in vivo sound printing (DISP), uses liposomes, tiny vesicles composed of lipids and containing an active substance. In this case, low-temperature-sensitive liposomes loaded with cross-linking agents are injected into the body with a prepolymer solution.
The application of ultrasound results in local heating of the targeted area by around five degrees Celsius, causing the liposomes to release their contents, initiating the printing of the polymer structure in a precise location.
In theory, this technique makes it possible to create customised solid hydrogel structures inside the body. The idea is to be able to print complex, functional structures inside the body, such as medical devices or repair cells, which can be used for regeneration treatments or to replace damaged tissue.
Ultimately, the technique could be used for biological monitoring of internal vital signs, and even help in the treatment of cancer. The next, even more ambitious step will be to use artificial intelligence to improve the precision of printing in moving organs, such as a beating heart.
The research is published in the Science journal. – AFP Relaxnews
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