Researchers say interstitial fluid could replace blood to monitor health and well-being – ScienceDaily

Researchers say interstitial fluid could replace blood to monitor health and well-being – ScienceDaily

The next frontier of continuous health surveillance might be superficial.

Biomedical engineers at the University of Cincinnati say interstitial fluid, the aqueous fluid found between and around cells, tissues or organs in the body, could provide an excellent medium for early disease detection or long-term health monitoring.

In an article published in the magazine Nature Biomedical Engineeringthey outlined the potential benefits and technological challenges of using interstitial fluid.

“Why we consider it a valuable diagnostic fluid is the continuous access. You can’t just take continuous measurements with blood,” said Mark Friedel, a UC graduate student and co-lead author of the study.

“Can you imagine spending your day with a needle stuck in your vein all day? So we need other tools.”

Researchers are looking for alternatives to monitor a person’s health and well-being. Sweat is a good medium to measure certain things like stress or anxiety because it contains hormones like cortisol. But the body is stingy with other chemicals that aren’t as easily released in sweat, Friedel said.

“Sweat glands are big filters that don’t let anything through,” he said. “So more than half of the things we want to monitor don’t have access to sweat at all.”

Blood is the gold standard for health monitoring. But humans also have liters of interstitial fluid, which make up up to 15% of their body weight.

“The key feature of blood that makes it so beneficial is that we understand blood really well,” Friedel said. “If you have something in your blood, we know what’s going to happen to your heart or your liver,” he said.

Researchers said interstitial fluid contains many of the same chemicals as blood in the same proportions, offering a potential alternative to costly and time-consuming lab work.

The study outlined the different ways doctors can collect interstitial fluid, from sucking on the skin to using microdialysis.

“As biomedical engineers, one of our greatest goals is to help people better manage their health by making diagnostics more accessible,” said co-lead author Ian Thompson of Stanford University.

“A major barrier to this accessibility is that most current diagnostics rely on blood sampling, which can be painful and requires trained personnel to perform. Therefore, in recent years there has been increased interest in using interstitial fluid just under the skin as a diagnostic sample that is more accessible and less painful to extract.”

At UC College of Engineering and Applied Science Professor Jason Heikenfeld’s Novel Devices Lab, students are developing sensors to measure hormones and other chemicals in interstitial fluid. They use microneedles less than 1 millimeter long that pierce the skin through a tiny spot.

“If you had a splinter, it probably went deeper into your skin than our microneedles,” Friedel said. “They are generally painless. I don’t feel it most of the time. The most awkward part is removing the tape holding the device down.”

But even if you don’t know it’s there, your body does, Friedel said. And that tiny reaction can affect test results.

“There’s a Schrodinger observer effect with interstitial fluid. Every time you try to collect it and try to measure it, you’re inherently changing the fluid itself,” Friedel said. “If you stick a needle in your skin, your body becomes inflamed and then yours [sample] change levels. For continuous biomonitoring, we want to know these concentrations as they are when not pricked with a tiny needle.

“That’s why it’s such a challenging liquid that hasn’t been used outside of diabetes surveillance.”

But researchers say interstitial fluid holds tremendous potential for health monitoring through wearable technology. This could help doctors track the effectiveness of drugs to ensure the right dosage or diagnose diseases early by monitoring the immune system.

But Friedel said there is still a lot to learn.

“We’re trying to open the box and read the instructions inside to understand what’s in the interstitial fluid and the potential for exploitation,” he said.

Friedel and Thompson worked with co-author Heikenfeld, UC’s James L. Winkle College of Pharmacy, Sandia National Laboratories in New Mexico, and Southeast Missouri State University.

The study was funded by grants from the National Science Foundation, the US Air Force Office of Scientific Research, and the US Office of Naval Research.

Leave a Reply

Your email address will not be published. Required fields are marked *