News, Analysis, Trends, Management Innovations for
Clinical Laboratories and Pathology Groups

Hosted by Robert Michel

News, Analysis, Trends, Management Innovations for
Clinical Laboratories and Pathology Groups

Hosted by Robert Michel
Sign In

International Team of Scientists Develop Smart Diaper That Alerts Parents When It Is Soiled and Needs to Be Changed

Not the first smart diaper to come along, but consumers seem unready for diapers that can flag urinary tract infections and other biomarkers usually tested by clinical laboratories

Will wonders never cease? For centuries, parents had only their own senses to determine when infants needed diaper changing. Today, however, caregivers can rely on “smart diapers” to send alerts when a diaper is soiled. Crying, smelly babies may no longer be the gold standard in diaper management. But are smart diapers practical?

Scientists at Penn State University in collaboration with scientists from the Hebei University of Technology and Tianjin Tianzhong Yimai Technology Development Company in China think so.

Funded by the National Institutes of Health (NIH) and the National Science Foundation (NSF), Penn State’s new smart diaper is based on a simple pencil-on-paper design that utilizes an electrode sensor array treated with a sodium chloride solution that detects dampness when urine is present.

The sensor array is “so cheap and simple” it “could clear the way for wearable, self-powered health monitors for use not only in ‘smart diapers’ but also to predict major health concerns like cardiac arrest and pneumonia,” a Penn State new release noted.

However, clinical laboratory managers following similar developments probably know that this is not the first scientific effort to develop a smart diaper that uses some type of sensor to detect a biomarker and issue an alert to the wearer or caregivers.

For example, nine years ago, In “New ‘Smart Diaper’ Tests Baby’s Urine for Urinary Tract Infections, Dehydration, and Kidney Problems—then Alerts Baby’s Doctor,” Dark Daily reported on a digital smart diaper invented by New York startup Pixie Scientific that constantly monitors a baby’s health to detect urinary tract infections, kidney problems, or dehydration before the health issue escalates. That smart diaper also uses a smartphone app to send data to the baby’s doctor.

In this latest research effort, the scientists published their findings in the journal Nano Letters, titled, “Pencil-on-Paper Humidity Sensor Treated with NaCl Solution for Health Monitoring and Skin Characterization.”

Huanyu "Larry" Cheng, PhD

“Our team has been focused on developing devices that can capture vital information for human health,” said Huanyu “Larry” Cheng, PhD (above), the James L. Henderson, Jr. Memorial Associate Professor of Engineering Science and Mechanics at Penn State in a news release. “The goal is early prediction for disease conditions and health situations, to spot problems before it is too late.” This is yet another example of how researchers are working to take more testing out of clinical laboratories and offer unique assays that can be used as wearables—whether as a diaper, a skin patch, or a smart watch. (Photo copyright: Penn State University.)

This Smart Diaper Is as Simple to Use as Paper and Pencil

The Penn State sensor array takes advantage of how paper naturally reacts to wetness and utilizes the graphite in pencil marking to interact with the water molecules and sodium chloride.

Once the water molecules are absorbed by the paper, the sodium chloride solution becomes ionized and electrons start to stream towards the graphite. This movement sets off the sensor, which is extremely sensitive to humidity. According to the study, the sensor can provide accurate readings over a wide range of humidity levels, from 5.6% to 90%.

“We wanted to develop something low-cost that people would understand how to make and use, and you can’t get more accessible than pencil and paper,” said Li Yang, PhD, a professor in the School of Artificial Intelligence at China’s Hebei University of Technology and one of the authors of the study, in the Penn State news release.

“You don’t need to have some piece of multi-million-dollar equipment for fabrication. You just need to be able to draw within the lines of a pre-drawn electrode on a treated piece of paper. It can be done simply and quickly.”

The diaper is connected to a tiny lithium battery. When the sensor recognizes an increase in humidity the battery powers transmission of the change to a smartphone via Bluetooth technology. This notification informs caregivers that it is time to change the diaper.

“That application was actually born out of personal experience,” explained Huanyu “Larry” Cheng, PhD, James L. Henderson, Jr. Memorial Associate Professor of Engineering Science and Mechanics at Penn State, one of the authors of the study and father to two young children. “There’s no easy way to know how wet is wet, and that information could be really valuable for parents. The sensor can provide data in the short-term, to alert for diaper changes, but also in the long-term, to show patterns that can inform parents about the overall health of their child.”

Do Consumers Want Smart Diapers?

Research into such wearable sensors has been gaining momentum in the scientific community as a novel way to detect and deal with several medical conditions. The Penn State team hopes that devices such as their smart diaper can be used in the future to alert caregivers about the overall health of their children and clients.

“Our team has been focused on developing devices that can capture vital information for human health,” Cheng said. “The goal is early prediction for disease conditions and health situations, to spot problems before it is too late.” 

Previous research teams have had similar smart diaper goals.

In “Researchers in Japan Have Developed a ‘Smart’ Diaper Equipped with a Self-powered Biosensor That Can Monitor Blood Glucose Levels in Adults,” we covered how a team of researchers at Tokyo University of Science (TUS) in Japan had developed a diaper that detects blood glucose levels in individuals living with diabetes, a debilitating illness.

However, these types of products have yet to gain significant popularity with consumers. Regardless, sales projections for smart diapers remain positive.

According to a MarketsandMarkets report, the smart diaper market, estimated to be $646 million (US) in 2021, is expected to surpass $1.5 billion by 2026. The demand for smart diapers, the report notes, is increasing due to:

  • Growing elderly populations,
  • Rising disposable incomes,
  • Increasing personal hygiene awareness,
  • Growing populations in emerging countries, and
  • Expanding preference for advanced technology when it comes to health.

So, it’s uncertain if consumers are now ready for a device in their baby’s diaper telling them it’s time for a change. Regardless, researchers will likely continue developing tools that combine new diagnostics with existing products to help people better understand and monitor their health and the health of their loved ones.

Meanwhile, clinical laboratory managers and pathologists can remain on the alert for future published studies and press releases announcing new wearable items containing sensors, such as smart diapers. The unanswered question is whether both consumers and healthcare professionals will consider these novel inventions useful devices in the care of young and old alike.

—JP Schlingman

Related Information:

Researchers Developed a “Smart Diaper” That Sends Notifications to Parents’ Phones

New Sensor Enables ‘Smart Diapers,’ Range of Other Health Monitors

Pencil-on-Paper Humidity Sensor Treated with NaCl Solution for Health Monitoring and Skin Characterization

Diaper Which Signals Time for Change by Chinese Team

New ‘Smart Diaper’ Tests Baby’s Urine for Urinary Tract Infections, Dehydration, and Kidney Problems—then Alerts Baby’s Doctor

Researchers in Japan Have Developed a ‘Smart’ Diaper Equipped with a Self-powered Biosensor That Can Monitor Blood Glucose Levels in Adults

Smart Diapers Market by End-Use (Babies, Adults), Technology (RFID Tags, Bluetooth Sensors), and Geography (North America, Asia Pacific, Europe, and Rest of World) (2022—2026)

The Smart Diaper is Coming. Who Actually Wants It?

Researchers in Japan Have Developed a ‘Smart’ Diaper Equipped with a Self-powered Biosensor That Can Monitor Blood Glucose Levels in Adults

The ongoing study shows promise in the general development of self-powered wearable biosensors, the researchers say, in a development that has implications for clinical laboratory testing

Years back, it would be science fiction to describe a wearable garment that can not only measure an individual’s biomarkers in real-time, but also generates the power the device needs from the very specimen used for the measurement. Clinical laboratory managers and pathologists may find this new technology to be an interesting milestone on the path to wearable diagnostic devices.

With cases of diabetes on the rise across the globe, innovative ways to monitor the disease and simplify care is critical for effective diagnoses and treatment. Now, a team of researchers at Tokyo University of Science (TUS) in Japan have recently developed a diaper that detects blood glucose levels in individuals living with this debilitating illness.

Of equal interest, this glucose-testing diaper has a self-powered sensor that utilizes a biofuel cell to detect the presence of urine, measure its glucose concentration, and then wirelessly transmit that information to medical personnel and patients. The biofuel cell generates its own power directly from the urine.

Glucose in urine provides valuable data regarding blood sugar levels and can be used as an alternative to frequent blood draws to measure those levels. Monitoring the onset and progression of diabetes is crucial to making patient care easier, particularly in elderly and long-term care patients. Widespread use of these diapers in skilled nursing facilities and other healthcare settings could create an opportunity for clinical laboratories to do real-time monitoring of the blood sugar measurements and alert providers when a patient’s glucose levels indicate the need for attention.

“Besides monitoring glucose in the context of diabetes, diaper sensors can be used to remotely check for the presence of urine if you stock up on sugar as fuel in advance,” said Isao Shitanda, PhD, Associate Professor at the Department of Pure and Applied Chemistry, Faculty of Science and Technology, Tokyo University of Science, in a TUS press release. “In hospitals or nursing care sites, where potentially hundreds of diapers have to be checked periodically, the proposed device could take a great weight off the shoulders of caregivers,” he added.

The TUS researchers published their findings in the peer-reviewed journal ACS Sensors, titled, “Self-Powered Diaper Sensor with Wireless Transmitter Powered by Paper-Based Biofuel Cell with Urine Glucose as Fuel.”

Creating Electricity from Urine

Through electrochemistry, the scientists created their paper-based biofuel cell so that it could determine the amount of glucose in urine via reduction oxidation reactions, or redox for short. Using a process known as “graft polymerization,” they developed a special anode that allowed them to “anchor glucose-reactive enzymes and mediator molecules to a porous carbon layer, which served as the base conductive material,” the press release noted.

The biosensor was tested using artificial urine at different glucose levels. The energy generated from the urine then was used to power up a Bluetooth transmitter to remotely monitor the urine concentration via a smartphone. The TUS researchers determined their biofuel cell was able to detect sugar levels present in urine within one second. The diaper with its sensor could help provide reliable and easy monitoring for diabetic and pre-diabetic patients.

“We believe the concept developed in this study could become a very promising tool towards the general development of self-powered wearable biosensors,” Shitanda said in the press release.

Isao Shitanda, PhD

According to the Isao Shitanda, PhD (above), lead author of the TUS study, 34.2 million people, or just over 10% of the US population, were diagnosed with diabetes in 2020. The federal Centers for Disease Control and Prevention estimates that an additional 7.3 million people have diabetes and are undiagnosed. A self-powered biosensor that detects diabetes and prediabetes in urine could help clinical laboratories and doctors catch the disease early and/or monitor its treatment. (Photo copyright: Tokyo University of Science.)

The World Health Organization (WHO) estimates that 422 million people globally were living with diabetes in 2014, and that 1.5 million deaths could be attributed directly to diabetes in 2019.

Other “Smart Diaper” Products

The Lumi by Pampers smart diaper contains RFID sensors that detect moisture and alert parents or caregivers when it is time to change the baby’s diaper. These smart diapers help prevent skin irritations and other health issues that can arise from leaving a soiled diaper on for too long. And in “New ‘Smart Diaper’ Tests Baby’s Urine for Urinary Tract Infections, Dehydration, and Kidney Problems—Then Alerts Baby’s Doctor,” Dark Daily reported on a smart diaper developed by Pixie Scientific of New York that could test a baby’s urine for various urinary conditions.

A panel of colored squares embedded on the front of the diaper changed color if specific chemical reactions fell outside normal parameters. If such a color change was observed, a smart phone application could relay that information to the baby’s doctor to determine if any further testing was needed.

Since we wrote that ebriefing in 2013, Pixie Scientific has expanded its product line to include Pixie Smart Pads, which when added to a diaper, enable’s caregivers to monitor wearers for urinary tract infections (UTI) and report findings by smartphone to their doctors.

These examples demonstrate ways in which scientists are working to combine diagnostics with existing products to help people better manage their health. Wearable electronics and biosensors are increasingly helping medical professionals and patients monitor bodily functions and chronic diseases.

As clever as these new wearable devices may be, there is still the need to monitor the diagnostic data they produce and interpret this data as appropriate to the patient’s state of health. Thus, it is likely that pathologists and clinical laboratory professionals will continue to play an important role in helping consumers and providers interpret diagnostic information collected by wearable, point-of-care testing technology.

JP Schlingman

Related Information

Making Patient Care Easier: Self-powered Diaper Sensors That Monitor Urine Sugar Levels

Self-Powered Diaper Sensor with Wireless Transmitter Powered by Paper-Based Biofuel Cell with Urine Glucose as Fuel

National Diabetes Statistics Report, 2020

WHO Fact Sheet on Diabetes

The Smart Diaper is Coming. Who Actually Wants it?

What Is a Smart Diaper, and How Does It Work?

Are Smart Diapers Safe?

New ‘Smart Diaper’ Tests Baby’s Urine for Urinary Tract Infections, Dehydration, and Kidney Problems—Then Alerts Baby’s Doctor

Synthetic Biologists Demonstrate Ability to Rapidly Create Cheap, Accurate In Vitro Diagnostics Tests That Could Eventually Help Pathologists Diagnose Disease

Wyss Institute develops prototype Ebola test in less than 12 hours with $20 in materials, perhaps paving the way for inexpensive paper-based diagnostic tests with a wide range of applications outside the medical laboratory

One goal of many synthetic biology researchers is to create in vitro diagnostic testing systems that produce results that are as accurate as those produced in today’s state-of-the-art clinical laboratories, yet are much cheaper to run because they incorporate low-cost materials, such as paper.

Recently, two teams of researchers worked to demonstrate how several synthetic biology methods, when combined with programmable paper-based diagnostic platform, could detect antibiotic-resistant bacteria and strain-specific Ebola virus. These findings were published in a peer-reviewed medical journal last fall.

Such cell-free circuits embedded in paper could be the breakthrough in synthetic biology that leads to pocketsize blotter tests that can detect such diseases as Ebola in the field.  Should this line of research be applied to clinical settings, pathologists and medical laboratory scientists could soon be processing bandages that change colors in the presence of certain bacteria, or examining paper-based clothing infused with diagnostic laboratory tests that react to bio-markers specific to a chronic disease patient’s condition. (more…)

New ‘Smart Diaper’ Tests Baby’s Urine for Urinary Tract Infections, Dehydration, and Kidney Problems—Then Alerts Baby’s Doctor

Clever entrepreneur thinks up inventive way to truly do clinical laboratory tests at the ultimate point of care and use a smart phone application to alert the doctor

With the advent of digital technology and smartphones, medical laboratory testing is moving out of the central laboratory and into the bedside, homes and now into diapers! A new digital “Smart Diaper” invented by New York startup Pixie Scientific constantly monitor’s a baby’s health to detect urinary tract infections, kidney problems, or dehydration early, before the health issue escalates.

‘Smart Diaper’ Tweets When It Detects a Health Problem (more…)

;