The frozen microneedle patch can inject drugs under the skin and then melt and disappear on its own
Unlike the large hypodermic needles that need to be long enough to reach the arm veins, the microneedles are less than 1 mm in length, which means they only penetrate the skin a short distance, not within the distance of the nerve endings, so they It is almost completely painless.
Usually, the microneedles themselves are made of biodegradable polymers that can be dissolved to release the payload, which may be drugs, vaccines, cells, or other therapeutic molecules. But in the new study, researchers at City University used a simpler material-ice to make it.
The principles of these frozen needles are basically the same. The treatment cells are loaded into the microneedles, although in this case they are paired with a cryoprotectant and then frozen in ice. Once the microneedles enter the skin, they will detach from the backing patch, and the patient’s body temperature will melt them and send their load out.
The team stated that the Compared with the needle system, the use of ice has some advantages. The most obvious is that it is a simpler material than biodegradable polymers, they also leave less waste, and ice can also preserve cells for long-term refrigeration. Of course, on the other hand, the requirement to keep frozen may be a disadvantage of transportation and storage.
In the test, the researchers used low-temperature needles to treat cancer in mice. They loaded the patch with ovalbumin pulsed dendritic cells, which is a cancer immunotherapy, and found that the immune response triggered by it was better than subcutaneous or intravenous injection.
This is an interesting turning point, but whether it can work in the real world has yet to be further tested. The team pointed out that other loads can also be integrated into the device.
The main author of the study Xu Chenjie The doctor said: “The application of our equipment is not limited to the delivery of cells.” This device can also package, store and deliver other types of biologically active therapeutic agents, such as proteins, peptides, mRNA, DNA and vaccines. I hope this device provides clinics with an easy-to-use and effective alternative treatment method”.
The research was published in the journal Nature Biomedical Engineering.