mouth on, pill in, swallow. So it is not always easy. Some drugs, Insulin for example, are too unstable to survive the way to the mucous membranes of the stomach and intestines. The stomach acid attacks the molecule, and a thick mucus layer forms a further barrier before it can reach the blood vessels. For this reason, you must inject, for example, a diabetic her Insulin every day and can't just swallow a pill.
The proof that it could go differently, deliver Alex Abramson from the Massachusetts Institute of Technology (mit) and his colleagues this week in the journal "Science". The researchers have developed a capsule to Swallow, which can be aligned independently to the gastric mucosa and medication syringes.
the tip of The needle itself is berry from Insulin
The capsule with the name of SOMA (self-orienting mm-scale applicator) is about as big as a blueberry. In its interior, there is a little needle whose tip is made of a compressed, freeze-dried Insulin is hiding. The shaft, as well as the capsule, made of a biodegradable Polymer degradation. He is connected with a tiny stainless steel spring, which is held by a device made of caramelized sugar under voltage.
Will swallowed the capsule, dissolves the gastric fluid, the sugar, the spring releases and lets the needle in the stomach wall. There, the Insulin is distributed from the needle tip and the blood taking vessels to the vital drug. The stomach wall with a thickness of about four to six millimeters seems more appropriate than the 0.1 - to two-Millimeter-thin lining of the intestine. In addition, according to the authors, regenerate the stomach tissue quickly by the layer of mucus closes the temporary Defective.
An African tortoise as Inspiration
But the mechanism can exert its effect only when the capsule is properly seated skin around the mucous membrane. For this, the scientists developed a special technique. The Mini-apparatus is, after it arrived, the gravity at the bottom of the stomach wall, no matter how he ends up there.
As a model served them turtle the in Africa living Panther. The tanks of the animal, similar to a Cathedral, steep, upward convex with a corner at the highest point. This design allows the turtle to roll easily back into normal position when it is located on the back. With computer models, the researchers transferred this model to their micro-capsule.
capsules of this Form of brought in the experiments faster by itself in the Vertical, as such, in the form of spherical or ellipsoidal shape: From 85 percent of all initial positions, they needed to a maximum of 100 milliseconds, in order to raise himself up. This is also important so that the capsule remains in place, even if it moves or the stomach growls.Lie down, straighten up, and shoot A needle out of a freeze-dried active substance, then lands in the mucosa and is absorbed .Illustration: A. Hupalowska, A. Abramson, M. M. Karim / TSP
The technique lowered the bluzucker mirror is exactly as strong as a syringe
so Far, the researchers have tested the capsule in rats and pigs. How quickly the Insulin in the stomach wall dissolves, you can influence the design of the capsule, write in your article. In the experiments, it took about an hour, until all the Insulin has been absorbed into the bloodstream. It managed, therefore, to lower the blood glucose level of the animals to a similar level as the usual injections under the skin. The researchers were able to with the technology, up to five milligrams of Insulin to be administered. This is comparable to a dose, the patients with type 2 injection for Diabetes.
so Far, Ambramson and his colleagues were able to demonstrate the effectiveness of the capsule only in the case of animals whose stomach was empty. However, they have developed a membrane, which is in place to prevent such food particles trigger the spring mechanism in advance.
Before the technology will be tried on people, it must be examined in addition to the release of insulin, among other things, whether the repeated punctures may cause damage to the stomach wall in a sustainable way. In the experiments, the muscle layer of the stomach remained at least intact. Pain should not cause the Mini-injections anyway, because the stomach wall has receptors no pain.
Also inflammatory reactions of the body against the capsule could not be determined by the researcher. As a trigger, the stainless steel spring to come especially in question. However, it seems as if they could be normally excreted with the stool.
The capsule could also take immunosuppressants
The tire WITH a-Team wants to the technology with the Danish company Novo Nordisk a market-ready product to develop further. "We hope that the capsule a day can help diabetics and other patients whose medications have to be used as a syringe, or Infusion," said co-author Robert Langer. Especially it is suitable for medicines from proteins: such as immunosuppressive agents, for example against rheumatoid Arthritis or inflammatory bowel disease. Also, RNA or DNA therapies could be possible. When exactly, is still unclear. That the principle works, however, have proved the researchers now for the first time.