A patch may one day help patients be able to control their diabetes. Scientists have created a synthetic patch filled with natural beta cells that can secrete doses of insulin to control blood sugar levels.

Beta cells usually can be found in the pancreas. There, these cells naturally produce insulin for the body. In healthy people, the cells produce, store and release insulin to help process sugar that builds up in the bloodstream. For people with diabetes, though, these cells are unable to produce enough insulin to keep blood sugar levels under control.

Diabetes currently affects 387 million people worldwide. That number is expected to rise to 500 million by 2030. That's why it's so important to find ways to help regulate this disease.

Researchers have long looked at transplanting insulin-producing cells as an alternative treatment for diabetes. The first successful transplant occurred in 1990; since then, hundreds of patients have had the same procedure. However, only a few of these treated patients achieve normal blood sugar levels since many of the transplants are rejected, or the medications used to suppress the immune system interfere with the beta cells and insulin.

Now, though, researchers have created a patch that may help. The patch is made of hundreds of microneedles which were filled with thousands of beta cells that were encapsulated into microcapsules made from biocompatible alginate. When the patch is put on a person's skin, the microneedles poke into the person's capillaries and blood vessels. This allows the insulin to be released in a controlled manner.

Currently, the researchers have only tested the patch on mice. However, the mice quickly achieved blood sugar levels that were normal with the patch.

"Managing diabetes is tough for patients because they have to think about it 24 hours a day, seven days a week, for the rest of their lives," said John Buse of UNC School of Medicine. "These smart insulin approaches are exciting because they hold the promise of giving patients some time off with regards to their diabetes self-care. It would not be a cure but a desperately needed vacation."

The findings are published in the journal Advanced Materials.