Fluorescence Sensor Diagnoses Diabetes

A microchip that detects fluorescent signatures of antibodies associated with Type 1 diabetes could aid in prevention and early intervention.

Created by a team from the Stanford University School of Medicine, the portable gold plasmonic microchip provides near-infrared fluorescence-enhanced detection of islet cell-targeting autoantibodies in blood samples. Glass plates form the base of each microchip and are coated with gold nanoparticles that intensify the fluorescence signal and enable more reliable antibody detection.

“The autoantibodies truly are a crystal ball,” said lead researcher Dr. Brian Feldman, assistant professor of pediatric endocrinology at Stanford. “If you have one autoantibody linked to diabetes in your blood, you are at significant risk. With multiple autoantibodies, it’s more than a 90 percent risk.”

The device is also able to distinguish between Type 1 and Type 2 diabetes, both of which have traditionally only been characterized by blood sugar levels.

More efficient testing has become crucial in recent years, the researchers said, as medical professionals have seen changes to groups diagnosed with diabetes. Type 1 has historically impacted children, while Type 2 has affected mainly overweight adults. But such categorization is no longer so clear-cut, according to the researchers, thanks to changes in adults’ lifestyles and factors such as the childhood obesity epidemic.

“With the new test, not only do we anticipate being able to diagnose diabetes more efficiently and more broadly, we will also understand diabetes better — both the natural history and how new therapies impact the body,” Feldman said.

The microchip is inexpensive to manufacture and quick to produce results, the researchers said. A smaller amount of blood is required for testing, too — about as much as is obtained from a finger prick — and unlike traditional testing methods, there is no radioactivity involved.

“There is great potential to capture people before they develop the disease, and prevent diabetes or prevent its complications by starting therapy early,” Feldman said, noting that early, aggressive treatment of Type 1 diabetes has been shown to improve patients’ long-term health.

The work was funded by grants from Stanford's SPARK program, the National Institutes of Health, the National Cancer Institute, the Juvenile Diabetes Research Foundation, Stanford Bio-X, Genentech and the Child Health Research Institute at Stanford.

The research was published in Nature Medicine (doi: 10.1038/nm.3619).

For more information, visit www.med.stanford.edu.