#INTERSTITIAL FLUID SKIN#
#INTERSTITIAL FLUID PATCH#
#INTERSTITIAL FLUID FULL#
#INTERSTITIAL FLUID TRIAL#

“If you want to look at what accumulates in the skin over time, this may provide a way to obtain information about those kinds of exposures,” Prausnitz says. This discovery could set the stage for use of the microneedle technique for dermatological and toxicology studies. While not all the compounds unique to the ISF could be analyzed, the research team identified components of products that are applied to the skin-such as hand lotions-and pesticides that may enter the body through the skin. “We found that some of the compounds were unique to the ISF, or enriched there, and that is what we were hoping to find.”

#INTERSTITIAL FLUID FULL#

“The skin is metabolically active, and it is full of cells that are changing the fluid,” Prausnitz says. However, about 12% of the chemical species were not found in the blood, and others were found in the ISF at higher levels than in the blood. Overall, there were about 10,000 unique compounds, most of which were also found in the blood samples. The extracted fluid was analyzed at Emory University using liquid chromatography-mass spectrometry techniques to identify the chemical species it contained. The procedure was well tolerated by the volunteers, and the microscopic pores healed quickly within a day, with minimal irritation. The overall extraction procedure took about 20 minutes for each test subject. In their studies, the researchers found that if they slowly ramped up the suction after inserting the microneedles, they could obtain fluid clear of blood. Though major blood vessels don’t exist in the outer layers of skin, capillaries there can be damaged by the insertion of the microneedles. To accurately determine the biomarkers available in the ISF, the researchers needed to avoid getting blood mixed with the ISF. For comparison, they also took blood samples and obtained ISF using the older blister technique. The researchers then applied a suction to the area of skin containing the pores and obtained enough ISF to do three types of analysis.

#INTERSTITIAL FLUID PATCH#

By pressing the patch at an angle into the skin of 50 human subjects, they created shallow micropores that reached only into the outer layer of skin containing ISF. The researchers, led by first author Pradnya Samant, used a patch containing five solid stainless steel microneedles that were a hundredth of an inch in length. Indwelling instruments for monitoring glucose in ISF already exist, and other researchers have used surgically implanted tubing and vacuum-created blisters to extract ISF through the skin, but these techniques are not suitable for routine clinical diagnostic use.

“This microneedle-based technique could provide a minimally invasive and simple way to access this interstitial fluid to make it available for medical diagnostic and research applications.” Chair in Georgia Tech’s School of Chemical and Biomolecular Engineering. Because interstitial fluid is in direct communication with the cells, it should have information about the tissues themselves beyond what can be measured from testing the blood,” says Mark Prausnitz, Regents Professor and J. “Interstitial fluid originates in the blood and then leaks out of capillaries to bring nutrients to cells in the body’s tissues. Size comparison of a microneedle patch used to extract interstitial fluid versus a hypodermic needle used to obtain blood samples. Photo by Allison Carter, courtesy Georgia Tech. The study, conducted by researchers from the Georgia Institute of Technology and Emory University, was supported in part by the National Institutes of Health and Children’s Healthcare of Atlanta. 25 in the journal Science Translational Medicine.

#INTERSTITIAL FLUID TRIAL#

Results of a human trial on the microneedle-based ISF sampling is reported Nov. Because the dermal interstitial fluid doesn’t clot like blood, the microneedle-based extraction could offer a new approach for continuous monitoring of glucose and other key health indicators as well as provide a new source of information for routine clinical monitoring and diagnostic testing. Researchers have now developed a minimally invasive way to extract dermal interstitial fluid (ISF), which circulates between cells in bodily tissues, using a simple through-the-skin technique that could provide a new approach for studying the metabolic products of cells, obtaining diagnostic biomarkers, and identifying potential toxins absorbed through the skin. Biochemical information about the body most commonly comes from analysis of blood-which represents only 6% of bodily fluids-but valuable information may also be found in other bodily fluids that are traditionally hard to get.