Beetle hairs inspire glue-free skin monitoring patch


Schematic illustration of the adhesive patch with diving beetle–inspired suction chambers against rough and wet human skin. Photo courtesy McGill University

Researchers have developed an experimental device for monitoring skin health that attaches without adhesives by using micro-structures inspired by diving beetles.


In a press release on Aug. 31 research team member Bo-yong Park, a former postdoctoral researcher at The Neuro at McGill University in Montreal, noted the project was undertaken to try and overcome some of the limitations of existing non-invasive dermatology diagnostic devices.


“These devices tend to be less accurate, hard to use, and require expensive equipment to analyze results,” said Park. “The chemical adhesives used in the process can also cause skin irritation or sometimes damage, making them difficult to use repeatedly or for a long time. Maintaining adhesion in different conditions like a wet or a curved skin surface can also be very challenging.”


To try and address these limitations, the research team took inspiration from the adhesive hairs, called setae, of the male diving beetle Hydaticus pacificus. These hollow structures use suction to allow the insect to adhere to wet and irregular surfaces, the researchers note.


“We created micro-sized artificial suction cups that can collect and monitor body fluids while adhering to the skin. We embedded fluid-capturing hydrogels within the cavities of the cups to monitor pH levels,” said Park. “The hydrogel changes colour with differing acidity levels.”


The investigators also developed a software application to quantify pH levels from the colours of the hydrogels in the device, which change colour in response to changes in pH.


“We expect that this device will be applied to personalized skin treatment patches, medical adhesive materials, and diagnostic technologies. Based on the results of our research, we expect it could be used for on-site diagnosis of biomarkers for skin disease,” Park said.


The findings were published in Science Advances (June 16, 2021; 7(25):eabf5695).