The lives of diabetes patients could become easier if a new insulin-containing material makes its way into pills. Many people with diabetes take several insulin shots each day to control their blood sugar. They'd prefer to take the hormone orally, but it's difficult to protect doses as they pass through the acidic stomach and yet keep the insulin available for the small intestine to absorb.
Now, chemists at Purdue University in West Lafayette, Ind., have developed a new way to sneak insulin past the stomach and make it better able to cross the intestine's lining. Aaron C. Foss and Nicholas A. Peppas put the hormone inside microscopic balls of acid-sensitive polymers.
The nanoscale spheres contract in acidic environments and swell in nonacidic ones. By soaking the balls in a nonacidic solution containing insulin, Foss made them expand and absorb the drug. Then, he quickly increased the solution's acidity, and the balls contracted, holding the insulin tight inside.