With the ability to access critical biomarkers through the skin, this innovative patch from Georgetown researchers could shift the standard of care in diagnostics and drug delivery.
Researchers at Georgetown University have developed a technology that may replace the need for traditional blood testing: a non-invasive transdermal patch can detect biomarkers found in the bloodstream without drawing blood or inserting any devices into the body. The patch contains microheaters that reach 100 degrees Celsius to collect interstitial fluid from the surface of the skin.
Interstitial fluid is the vital liquid located in the spaces surrounding cells that transport oxygen and nutrients to cells throughout the human body, while removing waste products. The origin of this fluid is derived from blood plasma that leaks out of blood capillaries and eventually moves back into the bloodstream via the lymphatic system.
“The interstitial fluid, sometimes also called extracellular fluid, bathes every living cell in your body,” stated Makarand Paranjape, PhD, associate professor of physics and director of the Georgetown Nanoscience and Microfabrication Cleanroom Lab (GNuLab) in the College of Arts & Sciences in a news release. “It’s like a pre-filtered sample. When you draw blood, you have to filter down all the other stuff you don’t need. We don’t have to do that, so the interstitial fluid is ideal for detecting blood-borne biomarkers or biomolecules.”
The project originally began 25 years ago and was funded by the Department of Defense.
Over the past two decades, Paranjape has advanced this biomedical technology and built a portfolio of patents through Georgetown’s Office of Technology Commercialization, aiming to improve the quality of life for patients living with a broad range of chronic diseases.
Paranjape believes his patch, which he compares to a Band-Aid, will be beneficial for people who must have regular blood draws for disease maintenance and control, such as patients with diabetes, cancer, or heart disease.
Paranjape’s patch technology uses flexible polymers on an adhesive base, incorporating gold microheaters to create tiny pores in the skin, enabling the collection of interstitial fluid.
“You’re inserting a needle into your arm or abdomen and putting a sensor inside the body to detect blood glucose. Anytime you put something in your body, it’s going to be attacked by your own immune system,” he said.
Makarand Paranjape, PhD, associate professor of physics and director of the Georgetown Nanoscience and Microfabrication Cleanroom Lab (GNuLab) in the College of Arts & Sciences said, “When you’re talking about drug delivery and even monitoring biomolecules for diabetes, it’s all about the quality of life. Can that be improved? This technology, I feel, will do that.” (Photo credit: Georgetown University.)
Once the microheaters have been activated, the interstitial fluid exudes naturally from the pores in the skin and the patch is able to monitor biomarkers in the bloodstream. Because the temperatures applied to the skin and the generated micropores are shallow and do not reach nerve endings, the patch is pain-free. Patients also only need to change the patch once a day.
“That highly-controlled thermal pulse effectively removes only a microscopic portion of the top-most layer of dead skin. It’s essentially exfoliating that small area of skin to an extent that you’re creating a hair-sized micropore from the top of the skin extending to the living tissue,” Paranjape affirmed. “Once you get through that layer, there is plenty of interstitial fluid that actually comes up and out of the micropore since your heartbeat is providing pressure.”
Potential Beyond Diagnostics: A New Frontier for Drug Delivery
Paranjape developed the patch primarily with diabetics in mind but is hoping his device has further uses, including drug delivery. Transdermal patches for time-released drug delivery are available, yet this patch, according to Paranjape, is more effective as current patches on the market require existing drugs to be modified.
“Most of these patches require the drug in question to be tailored chemically to allow it to penetrate through intact skin. Ours does not,” he asserted. “We can use off-the-shelf drugs. We are creating tiny pores through the skin so the drug can easily enter and diffuse to the circulatory system.”
Paranjape also theorizes the patch could reduce pharmaceutical dosages, diminish medical waste and help curtail healthcare costs. His lab is currently working on adopting the patch for drug delivery in patients with Parkinson’s disease. He also plans to start a drug trial soon to help diagnose patients with cystic fibrosis.
Paranjape is hopeful that his patch-based platform technology will be utilized in the future to diagnose and treat patients with a wide array of illnesses and improve their quality of life.
“If there’s a marker in the blood that can be detected in the interstitial fluid, you can use the patch. If there’s a drug that can be used for the treatment of a condition, you can use the patch,” he said. “There’s a whole host of conditions that can be treated.”
— JP Schlingman
