High-Speed Camera Footage Shows a Water Jet Impacting a Water Droplet

YouTube videos of extremely slowed down, high-speed footage of objects breaking might seem like a bit of fun, raking in millions of views for uploaders.

However, scientists from MIT believe that by studying slow-motion footage of a jet of water squirting through a drop of liquid, they could identify methods for injecting fluids such as vaccines without the use of a needle, a press statement reveals.

Water droplets replace human skin for research experiments

Researchers from MIT, in collaboration with scientists from the University of Twente in the Netherlands, fired small jets of water through many different types of water droplets hundreds of times.

They used high-speed cameras to closely investigate the intricacies of each of the impacts. The videos, which were slowed down to 50,000 frames per second, are similar to famous strobe-light photographs of a bullet piercing an apple, first devised by MIT's Harold Edgerton.

Based on their water droplet investigations, the researchers were able to develop a model that predicts how a fluid jet will impact a water droplet, depending on its viscosity and elasticity. As human skin is a viscoelastic material, the model may be able to predict how fluids could be delivered through the skin without the use of a needle.

The right speed and density liquid harmlessly penetrates human skin

"With these experiments, we are getting all this knowledge, to inform how we can create jets with the right velocity and shape to inject into skin." David Fernandez Rivas, a research affiliate at MIT and professor at the University of Twente, explained in MIT's statement. The ultimate goal is to devise a method of needle-free injection that would do minimal damage to the skin. The team's findings so far have been published in the journal Soft Matter. 

Researchers linked to this study have already founded a startup called Portal Instruments, whose solution is marketed as a "highly innovative needle-free jet injection platform." The company's device uses an electromagnetic actuator that ejects hair follicle-thin streams of medicine at high speeds, allowing them to penetrate human skin.

The researchers on the latest study say that by closely investigating separate phenomena, such as the way the water jet could drag air bubbles into water droplets, they could fine-tune new methods for needle-free injection while avoiding bringing air bubbles into the body. The team next hopes to carry out more experiments using thicker materials that more closely resemble human skin, a development that may eventually lead to easy, painless administration of medicines that currently rely on needle injections.