Stress monitoring becomes something that folds naturally into health care
For decades, measuring the body's stress response has required clinical settings, trained professionals, and tools that often amplify the very anxiety they seek to quantify. A team at Tufts University has quietly reframed that problem by asking what already exists in daily life — and found their answer in dental floss. By embedding cortisol-detecting polymer sensors into a familiar hygiene tool, they have proposed that the most meaningful health data might be gathered not in a clinic, but in the two quiet minutes before bed.
- Chronic stress is measurable in the body but has long resisted simple, accurate, real-world tracking — leaving a dangerous gap between what clinicians need to know and what they can actually observe.
- Traditional stress monitoring methods — questionnaires, psychiatric evaluations, blood draws — are slow, expensive, and often introduce the very anxiety they attempt to measure.
- Tufts researchers engineered a cortisol sensor into a standard floss pick, using molecularly imprinted polymers that act like precision casts shaped to capture stress hormones drawn up through saliva during ordinary flossing.
- The sensor matches the accuracy of leading diagnostic tools while requiring no training, no clinic visit, and no disruption to routine — making continuous stress monitoring genuinely accessible for the first time.
- The underlying eMIP technology is already being adapted to detect estrogen, glucose, and cancer markers, with multi-biomarker simultaneous detection on the horizon, and a startup forming to bring the device to market.
Chronic stress leaves fingerprints on the body — in blood pressure, immunity, cognition — but capturing it accurately in real life has always been awkward. Questionnaires depend on memory and candor; clinical evaluations are costly and slow. There has been no simple way to track stress as it actually unfolds.
Sameer Sonkusale, a professor of electrical and computer engineering at Tufts, wanted to build something so ordinary that people would use it without thinking. Cortisol, the body's primary stress hormone, appears in saliva — and flossing, it turns out, is already a daily ritual that moves saliva through a narrow space. His team built a sensor into a standard floss pick: capillary action draws saliva up through the string, into the handle, and across electrodes coated with electropolymerized molecularly imprinted polymers — eMIPs. The technology works like a plaster cast, molding a polymer around a cortisol molecule, removing it, and leaving behind a binding site of exact chemical shape. When cortisol arrives, it fits, and is detected.
The sensor's accuracy rivals the best devices on the market, but its real advantage is that it requires no training, no clinic, no separate appointment. Sonkusale is careful to note its proper role: this is a monitoring tool, not a diagnostic one. Blood tests remain the standard for initial diagnosis, since saliva markers vary between individuals. But for someone already managing a cardiovascular condition or chronic illness, the floss sensor offers a way to track progress and catch problems early.
The eMIP approach also sidesteps a traditional bottleneck in biosensor development — no antibodies or specialized receptors need to be engineered for each new molecule. The same method can be adapted for estrogen, glucose, or cancer markers, and the team is exploring simultaneous multi-biomarker detection from a single saliva sample. Published in ACS Applied Materials and Interfaces, the work is part of a broader thread-based sensor program from Sonkusale's lab. He and his colleagues are now launching a startup to carry the floss sensor from the laboratory into everyday hands.
Chronic stress wears on the body in measurable ways—it raises blood pressure, weakens immunity, clouds the mind. But measuring that stress has always been clumsy: questionnaires that rely on what people remember or admit, psychiatric evaluations that are expensive and time-consuming. There's been no simple, accurate way to track stress as it actually happens in daily life.
Sameer Sonkusale, a professor of electrical and computer engineering at Tufts, and his interdisciplinary team set out to change that. They wanted to build a stress-monitoring device that wouldn't itself become a source of stress—something so ordinary that people would use it without thinking. Cortisol, the body's primary stress hormone, appears in saliva. So they asked a simple question: what if the tool for measuring it was something everyone already does?
The result is a dental floss sensor that looks like a standard floss pick—two prongs holding string, a flat plastic handle about the size of your index finger. When you floss, capillary action draws saliva up through a narrow channel in the string. The fluid moves into the handle and spreads across a set of electrodes. Those electrodes are coated with something called electropolymerized molecularly imprinted polymers, or eMIPs. The technology is nearly thirty years old, but its application here is elegant. An eMIP works like a plaster cast: a polymer is molded around a cortisol molecule, then that molecule is removed, leaving behind a binding site with the exact physical and chemical shape of cortisol. When free-floating cortisol molecules arrive, they fit into those sites and are detected.
The accuracy of the cortisol sensors matches the best devices currently on the market or in development. But the real advantage is accessibility. A person can use the floss at home, without training, without a clinic visit. Stress monitoring becomes something that folds naturally into health care rather than something that requires a separate appointment.
Sonkusale emphasizes an important boundary: the sensor is excellent for tracking a condition over time, not for diagnosing one in the first place. Blood tests remain the gold standard for initial diagnosis because saliva markers can vary between individuals. But once someone is diagnosed with a cardiovascular condition or another illness, the floss sensor makes it possible to monitor their progress easily and catch problems early enough to intervene.
The versatility of eMIP technology opens wider possibilities. The same approach can detect estrogen for fertility tracking, glucose for diabetes management, or cancer markers. The team is exploring whether multiple biomarkers can be detected simultaneously from a single saliva sample, which could improve monitoring of stress, heart disease, cancer, and other conditions. Sonkusale notes that the eMIP method sidesteps the traditional bottleneck in biosensor development: you don't need to engineer antibodies or specialized receptors for each new molecule. If a new stress marker is discovered, a polymer cast can be created quickly.
The research, published in ACS Applied Materials and Interfaces, is one of several thread-based sensor innovations from Sonkusale's lab. His team has also developed sensors embedded in fabric that detect gases, track metabolites in sweat, or measure movement, and transistors that can be woven into flexible electronics. Now Sonkusale and his colleagues are launching a startup to bring the dental floss sensor to market—moving a laboratory idea into the hands of people who need it.
Citas Notables
We didn't want measurement to create an additional source of stress, so we thought, can we make a sensing device that becomes part of your day-to-day routine?— Sameer Sonkusale, professor of electrical and computer engineering at Tufts
The eMIP approach is a game changer because it doesn't require extensive bioengineering of antibodies or receptors for each new marker—a polymer cast can be created in a short period of time.— Sameer Sonkusale
La Conversación del Hearth Otra perspectiva de la historia
Why dental floss specifically? Why not a toothbrush or a mouth rinse?
Because flossing is something people already do daily, and it's intimate enough to collect saliva reliably. The goal was to make measurement invisible—part of your routine, not an interruption.
How does the polymer actually remember the shape of cortisol?
It's molded around a cortisol molecule like a negative space. Once the original molecule is removed, what's left is a cavity with the exact fit. When new cortisol molecules float past, they lock into those cavities. It's recognition through shape and chemistry.
If it's so accurate, why can't doctors use it for diagnosis?
Saliva varies between people in ways blood doesn't. Two people with the same stress level might have different cortisol readings in their saliva. Blood is more standardized. But once you know what you're treating, the floss sensor is perfect for watching whether treatment is working.
What happens next?
The team is starting a company to manufacture and distribute it. The real test is whether people will actually use it at home, whether it integrates into real life the way they hope.
Could this work for other diseases?
That's the exciting part. The same polymer-casting approach works for any molecule that appears in saliva—estrogen, glucose, cancer markers. You could theoretically detect multiple conditions from one floss sample.
Does it feel like a gimmick, or is this genuinely useful?
It's genuinely useful because it solves a real problem: how do you monitor chronic conditions without making people go to clinics constantly? If it works in practice the way it works in the lab, it changes how people manage their health at home.