Researchers at The Ohio State University are studying the ability of the mosquito to insert a needle-like probe into your skin and draw blood for several minutes without you even noticing. They believe they can learn from nature's design of the mosquito to create a painless microneedle for medical purposes.
"Mosquitoes must be doing something right if they can pierce our skin and draw blood without causing pain," said Bharat Bhushan, Ohio Eminent Scholar and Howard D. Winbigler Professor of mechanical engineering at Ohio State.
In a recently published paper, Bhushan and his colleagues reported on their detailed analysis of the mosquito's proboscis. They identified four keys to how the insects pierce us without pain: use of a numbing agent; a serrated design to the "needle"; vibration during the piercing; and a combination of soft and hard parts on the proboscis.
"We can incorporate all of these elements into a microneedle design," Bhushan said. "Right now, needles are very simple. There hasn't been much innovation and we think there's a way to try something different." The study was jointly led by Bhushan and Navin Kumar, a professor at the Indian Institute of Technology, Ropar. Their results are published in the Journal of the Mechanical Behavior of Biomedical Materials.
Based on these findings, Bhushan envisions a microneedle with two needles inside. One would immediately inject a numbing agent. The second needle would draw the blood or inject the drug. This second needle, like the fascicle of the mosquito, would have a serrated design and be most flexible and softer at the tip and sides. It would also vibrate as it is inserted.
Bhushan said that a microneedle like this would be more expensive than a traditional needle and probably could not be used for such needs as pumping intravenous fluids or drawing a large amount of blood. But it could be useful for children or adults who are particularly phobic about the use of needles. "We have the materials and knowledge to create a microneedle like this," Bhushan added. "The next step is to find the funding support to create and test such a device."
Image: Researchers developed proposed needle using principles they learned from how mosquitoes pierce skin without pain. Image courtesy of Bhushan, Kumar, Guerra.