This Non-Electric Sling Uses Sunlight to Treat Newborn Jaundice

Jaundice is one of the most common conditions newborns face, and in a well-equipped hospital, treating it is routine: doctors place the baby under a specialized blue light that helps break down excess bilirubin in the blood. But that simple procedure depends on a reliable power supply and specialized equipment. Tens of millions of babies are born each year into places where neither is available, and for them the standard therapy might as well not exist. Left untreated, severe cases can cause lasting neurological damage.

Daniel John grew up seeing that gap firsthand. Born in Nepal, he watched limited health care access shape the lives around him long before he understood the mechanics of medicine.

“Growing up there, I saw a need for health care access, which is what made me interested in medicine in the first place, but then also a need for medical devices that are designed specifically for limited-resource settings that don’t require electricity,” John said, in a profile published by Michigan Medicine.

That observation set the course for what came next. As a mechanical engineering undergraduate at Calvin University, John began writing to physicians across the globe, posing a simple question: where were the biggest unmet needs for low-cost medical devices? Neonatal jaundice kept surfacing in the responses.

So he learned to sew. The earliest prototypes took shape in his college dorm room, stitched together with guidance from family members. “Relatives that knew how to sew taught me some of the basics, and those were some of the first devices that we iterated,” he said.

What came out of that work is the BiliRoo. At its core, it is an infant sling: the kind a parent uses to carry a baby against their chest. Built into the fabric across the infant’s back is a specialized filter that lets through the blue wavelengths of natural sunlight, the same ones hospitals replicate with their phototherapy lamps, while blocking the ultraviolet rays that could harm a newborn’s skin. Because the baby rides against the parent’s body, the sling also provides the skin-to-skin warmth and bonding that clinicians call kangaroo care. The name captures both sides of what the device does: bilirubin plus kangaroo.

John, now a medical student at the University of Michigan, found a key collaborator early in Dr. Tina Slusher at the University of Minnesota, one of the foremost researchers on neonatal jaundice in underserved settings. Together they produced a feasibility study published in Pediatric Research. A clinical trial is set for this summer, with manufacturers in South Asia already involved.

The device has gained recognition well beyond the lab. BiliRoo took first place at the 2026 Michigan Business Challenge, was named one of the top undergraduate inventions of 2025 by the National Inventors Hall of Fame and the U.S. Patent and Trademark Office, earned top hardware honors from the American Society of Mechanical Engineers, and won the Southwest Pediatric Device Consortium Prize at the Rice Business Plan Competition.

At Michigan, John is pursuing the Global Health and Disparities Path of Excellence under the mentorship of Dr. Shane Quinonez and working with Dr. Karl Desch in pediatrics. He is direct about what comes next.

“I plan to continue developing BiliRoo until it gets to the infants that need it the most,” he said.