Stanford University scientists say they have developed a new test for type 1 diabetes that will cost a fraction of the current price and could speed up diagnosis from days to hours. That could be useful anywhere, but especially in poorer countries where many people with diabetes go undiagnosed or misdiagnosed because the existing tests are too expensive to be widely offered.

In current tests, blood samples are sent to a lab, where radioactive materials are used to detect the cause of the disease: a so-called auto-antibody that attacks the insulin-producing cells in the pancreas. This test is labor-intensive and costs hundreds of dollars.

With the newly developed test, instead of sending a patient’s blood to a lab, a nurse or doctor could put the sample on a $20 chip roughly the size of a business card, along with a chemical that produces a fluorescent signal when it encounters auto-antibodies. A glass plate on the chip is coated with nanoscale islands of gold, which enhances the fluorescent signal, helping to ensure the test is reliable. It differentiates between type 1 diabetes, which causes the body to produce virtually no insulin, and type 2, in which the body does not produce enough insulin or is unable to use it effectively.

“In terms of cost, convenience, and speed, it’s likely to be a better solution,” says Joyce Lee, associate professor of pediatrics and communicable diseases at the University of Michigan, who was not involved in the study.

The researchers—led by Brian Feldman, assistant professor of pediatric endocrinology at Stanford University and senior author of a paper published this week in Nature Medicine—have filed for a patent on the chip and are in the process of launching a startup company that will seek approval from the U.S. Food and Drug Administration.