Scientists from Tufts University have learned to make silk microscopic needle for subcutaneous injection of drugs. This unusual medical device will inject safely and completely.
"Patch" with an array of needles applied to the desired location on the body. Microneedles discreetly pierce the top layer of skin of the patient, blood flow gradually giving them enclosed in medicine. Then the tiny "needles" are absorbed without harm to the skin and the environment.
There have silk microneedles and another plus. Most modern arrays of microscopic needles are manufactured in aggressive conditions (speech, above all, the microneedles made of plastic). A injected into these drugs are very sensitive and can be destroyed.
Silk microneedles in this sense is much "softer", as created from natural materials. Furthermore, the assurances creators of the microneedle can be configured so as to deliver drugs at a certain rate. And in silk microneedles can be added to tetracycline, then puncture the body will not make the infection. And finally, these "needles" of medicine is not necessary to store in the fridge — embedded in their preparation does not spoil.
Production of "patch" with microneedles begins with billet aluminum, which is the profile of the future of the array. The height of each up needles 500 micrometers, and the diameter of its tip — 10 micrometers. On the first aluminum form a layer of polydimethylsiloxane elastomer which forms the negative casting mold.
Then the aluminum profile is removed, and in its place "fill in" silk, mixed with medication. The material dries ready array of microneedles. It is separated from the mold, treated with water vapor. The entire process takes place at normal temperature and pressure. As a test experiment in silk microneedles scientists from the United States added horseradish peroxidase — an enzyme commonly used in molecular biology research.
By varying certain parameters, such as the drying of silk, the researchers learned how to adjust the rate of release of substances in the skin. All other features of novelty describes an article in Advanced Functional Materials.
Of course, silk (and what else others) microneedles can not always replace conventional syringes. However, at least in some areas of medicine innovative design is sure to find a use.