When you are sick and go to the hospital to see a doctor, whether you are injecting drugs or taking a blood test, you must have an injection. Injecting is not only painful, it can sometimes leave spots, and it is even at risk of infection, which makes many people cyanotic. Recently, American and Italian researchers collaborated to develop a microneedle with extremely strong tissue adhesion. This microneedle is minimally invasive, painless, and easy to use. It can completely replace hypodermic needles and prevent patients from seeing needles. .
Microneedles are microneedles that are only a few hundred micrometers long. They have received widespread attention because they do not cause intense pain when used. However, the currently developed microneedles have low tissue adhesion, which affects their usability as long-term drug delivery or biosensing tools.
This time, a research team composed of Rutgers University in the United States and the University of Pisa in Italy was inspired by some biological microstructures in nature, such as micro-hooks of parasites, barbs of bee legs, etc., using 4D printing methods to create extremely Microneedles with strong tissue adhesion. The so-called 4D printing method is to increase the dimension of time on the basis of 3D printing, so that the printed smart material changes shape at a set time.
Unlike traditional microneedles, this new type of microneedles have many barbs that can interlock with tissue when inserted into the tissue to enhance adhesion. The density and bending curvature of these barbs can be controlled by printing parameters and material composition. The researchers tested the tissue adhesion of microneedles using muscle tissue as a model, and the results showed that the new microneedles had 18 times the tissue adhesion of barbed microneedles, which ensured continuous drug release in the tissue. The researchers said that the 4D printed microneedle array is minimally invasive, painless and easy to use, and can replace traditional injection needles for medical tasks such as drug delivery and blood collection.