New Skin Patch Monitors Glucose and Delivers Diabetes Drugs

The wearable sweat monitoring patch on the skin. Image Credit: Hyunjae Lee and Changyeong Song

 
People with diabetes need to closely monitor their blood glucose levels multiple times every day, usually using a device that pricks their finger for a blood test to assess whether they need insulin shots or other drugs. Since blood collection and shots can be painful, not all patients do it as regularly as they need to—which can lead to dangerous fluctuations in their blood glucose levels.

Researchers have worked for years on methods to improve and even automate blood glucose monitoring and insulin/drug delivery. For example, insulin pumps make drug delivery easier, and recently designed artificial pancreas systems offer closed-loop monitoring and drug delivery. Now, researchers in Korea have just developed a wearable, and potentially disposable, glucose monitoring and drug-delivery system that uses sweat, not blood, to determine glucose levels.

The results, published today in Science Advances, suggest it’s a major upgrade. There are several differences between the artificial pancreas and the sweat-based monitoring system, according to lead author Hyunjae Lee, of Seoul National University in the Republic of Korea. While both devices can check blood glucose in real time and deliver necessary drugs, the artificial pancreas’s drug-delivery needles are permanently embedded subcutaneously, and the device itself is made of rigid plastic, which "might cause discomfort," Lee tells mental_floss.

The sweat-based system, on the other hand, is transfer-printed onto a thin silicone skin patch. It’s made of flexible and stretchable electronics, a series of stretchable graphene sensors—humidity, glucose, pH, and temperature—packed as closely as possible. The sensors’ electrodes are made from porous gold nanoparticles, whose structure helps create an electrochemically active surface area in order to analyze what’s in your sweat. Above a heating strip, which helps create humidity and generate sweat more quickly, is a film strip of drug-loaded microneedles, 0.6 inches by 0.8 inches. These are loaded with metformin, a drug used to control glucose in Type 2 diabetes. (At present, the sweat-based patch has not been tested on insulin, whose molecules are too big for delivery through the microneedles, though Lee hopes to work on designing one that can work with insulin in the future.)

Detail of the wearable sweat-analysis sensors. Image Credit: Hyunjae Lee and Changyeong Song

 
Sweat accumulates in the porous sweat-uptake layer of the patch, which also helps screen out negatively charged molecules, including drugs that may interfere with the glucose sensing. A waterproof band helps prevent the patch from peeling away from the skin. When the sweat covers the glucose and pH sensors, the measurements begin. "When blood glucose is high, [the] therapeutic part activates microneedle-based drug delivery," automatically, Lee explains.

Researchers adhered the patch to five healthy human subjects, ages 20 to 60. It takes 10–15 minutes for the device to generate enough sweat to measure glucose levels, though exercise could speed that process up. However, Lee says they took into account that for some people with diabetes, "sweat generation through exercise could be a burden." He adds, "Considering [that] point, we miniaturized sensor design that allows for reliable sweat analysis even with an infinitesimal amount of sweat."

The participants’ blood glucose levels were tested using a commercial glucose meter one hour before and after a meal as a comparison. The researchers found that the sweat-glucose sensor measurements were comparable to those of a commercial blood glucose assay kit.

Human clinical trials are not yet scheduled for the drug-delivery process, so to test this part of the system, Lee’s team turned to mice. They took 16 diabetic mice, 8 to 12 weeks old, and fasted them overnight before the experiment. They attached drug-loaded microneedles to their shaved abdomens, which had been stained with a special blue dye. Then, they used an embedded heating element to activate the microneedles, since the mice can’t produce enough sweat to do so. The microneedles' successful penetration of the skin was made visible by the blue dye.

The experimental groups of mice that received the drug delivery of metformin showed a significant decrease in blood glucose levels compared to the control groups that did not receive the drug. "In the animal experiment, we could confirm that blood glucose was continuously decreased and continued for six hours after microneedle therapy," Lee says.

While the system shows great success, Lee acknowledges there are adjustments to be made. "The sensor should be more sensitive and reliable to enhance accuracy of sweat-based glucose monitoring system," he says. In order to control the amount of drug delivered, they will also need to study "the correlation between sweat and blood glucose levels more thoroughly."

Despite the need for further research, Lee feels their device "can surely contribute to improve the quality of life of diabetic patients."

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Citroën
These Funky Glasses Are Designed to Reduce Motion Sickness
Citroën
Citroën

There's nothing like a sudden wave of nausea to ruin a scenic road trip or a cruise. According to Visuall, the French car company Citroën has made a product that allows you to fight motion sickness without medication.

Their glass-less spectacles, called SEETROËN, implement technology first developed by the French startup Boarding Ring. Motion sickness occurs when the information we receive from our inner ear doesn't match up with what we see in front of us. SEETROËN tackles this problem in a simple way: Liquid at the bottom of all four rings (two in front of the eyes, two at the peripheries) responds to gravity and changes in movement the same way the fluid in your inner ear does. By having an "artificial horizon" to look at when you're in the back of a bumpy car, your visual senses should realign with your sense of balance, and you'll no longer feel queasy.

The accessory isn't exactly fashionable, unless maybe you're going for a space-age look, but you shouldn't worry about appearing goofy for too long. After staring at a still object like a book through the glasses for 10 to 12 minutes, you can remove them and continue to enjoy the benefits as you proceed with your trip, the company claims.

SEETROËN is currently out of stock at Citroën's lifestyle store, with the next shipment estimated for September. The company claims the spectacles show positive results 95 percent of the time, and the technology it uses won an INNOV'inMed award for health innovation. But like with any new technology meant to treat a medical condition, users should be cautious. Time-tested ways to prevent motion sickness include sitting in the front seat of a car, eating something light before you travel, and focusing your gaze on something outside the nearest window.

[h/t Visuall]

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iStock
5 Simple and Painless Ways to Remove a Splinter
iStock
iStock

Splinters are as sneaky as they are annoying. You never see one coming, but once one gets embedded in you, you’re definitely going to feel it. The most common way to pull one of these out of your body is to grab a pair of tweezers and just start digging. While that might work for splinters that haven't lodged too deep into your body, it’s far from ideal for the ones completely under the surface. Plus, it hurts.

Thankfully, you don’t always need sharp instruments or a trip to the doctor to get rid of those stubborn splinters—there are plenty of items lying around your house right now that can help draw them out. So the next time you find yourself with a painful piece of wood or other material stuck in your foot, finger, etc. be sure to wash the affected area with soap and warm water and give one of these simple—and painless—remedies a try.

1. SOAK IT IN EPSOM SALTS.

Epsom salts are an incredibly versatile cure-all for common ailments like sunburn and sore muscles. But one of its lesser known uses is the fact that it can help bring deep splinters to the surface of your skin.

To get this to work, just dissolve a cup of the salts into a warm bath and soak whatever part of the body has the splinter. Failing that, you can also put some of the salts onto a bandage pad and leave it covered for a day; this will eventually help bring the splinter to the surface. Both methods help to draw the splinter out, which you can then pull out completely with a tweezer.

2. SLAP A BANANA PEEL ON TOP OF IT.

They can do everything from whiten your teeth to shine your shoes, but banana peels can also rid you of your splinter woes. Simply take a portion of a ripe peel and tape the inside portion over the area with the splinter. From there, the enzymes in the peel will get to work by softening your skin and helping the splinter move closer to the surface.

Some say just a few minutes is often all it takes, but if you can leave it on longer (especially overnight), you’ll have a better chance that the splinter will surface. Sometimes it will be drawn out far enough that it will come out on its own when you remove the peel; other times you may still need to use a pair of tweezers to finish the job. And if it doesn’t work after one night, replace the peel and leave it on for another day.

Don’t have a banana handy? You can also try a potato slice using essentially the same method: Place the skinless side on the area, hold in place with a bandage, and leave it on overnight. Then remove it and see if the splinter has surfaced.

3. MAKE A BAKING SODA PASTE.

First, before you do anything, clean the affected area with soap and water. Then combine a little water with ¼ of a tablespoon of baking soda to make a paste that you can then spread on the splinter. Once the paste is spread, cover the area with a bandage and keep it just like that for a full 24 hours.

You should notice that the splinter has made its way to the surface, where you can now simply just remove it. If you still can't get a hold of it, you can repeat the same procedure until the splinter is sufficiently brought above the skin.

4. USE SOME TAPE.

This method is best when a splinter is already drawn to the surface a bit but tweezers just won’t do. Simply take a piece of tape—go for something a little stronger, like duct tape—and place it over the splinter. Once the tape is secure (leave it on for a few minutes), gently pull it off. You may have to repeat this a few times to coax the splinter out. For a little added security, soak the area in warm water first to soften the skin.

5. VINEGAR OR OIL.

Another simple way to draw out that stubborn splinter is to soak the affected area in oil (olive or corn) or white vinegar. Just pour some in a bowl and soak the area for around 20 to 30 minutes, then eyeball the splinter and see where it is. If it looks closer to the surface, but not enough to pull out, soak it longer. Once it gets far enough out, just remove it and wash the area with soap and water.

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