It’s the size of a pen, weighs as much as two AA batteries, and works without a power source. A new microneedle device developed by researchers at the Georgia Institute of Technology has the potential to transform vaccine delivery as we know it.
Lead inventor and biomolecular engineering expert Saad Bhamla said the inspiration for the novel technology came from an unconventional source. “My lab figured out that you could use something all of us are familiar with on the Fourth of July when we do a barbecue—a barbecue lighter,” said Bhamla.
When lighters are clicked, a quick burst of electricity sets the gas ablaze to get the fire going. The lighter’s electric pulse mirrors a commonly-used laboratory technique known as electroporation. Here, brief pulses of electricity temporarily disrupt cell membranes, allowing the transport of molecules into the cell’s cytoplasm. This method is routinely used to deliver genetic materials such as mRNA to cells.
In principle, a similar approach could be used to deliver mRNA vaccines to people. However, technical complexities and high costs block the practicality and scalability of electroporation as a vaccine delivery strategy.
The researchers hypothesized that the humble barbeque lighter could help electroporation overcome these challenges. The internal mechanisms in lighters have a price tag a mere fraction of the thousands of dollars that electroporation machines cost. In addition, lighters don’t require the use of batteries or power sources to work.
The team combined their newly-developed battery-free electroporation technology with microneedles (tiny needles commonly used for cosmetic and skincare applications) to create the ePatch. Bundles of microneedles coated with genetic material penetrate to a depth just 0.01 of an inch below the surface of the skin. At the same time, the ePatch emits a small pulse of electricity to drive the vaccines into cells of the skin.
Putting their ePatch to the test, the innovators partnered with immunologists at the Emory University School of Medicine. The device was tested in mice using an experimental DNA-based vaccine for COVID-19 and yielded extremely promising results. The ePatch triggered a tenfold improved immune response compared to when the DNA vaccine was administered via a conventional intramuscular immunization. The researchers also did not notice any adverse effects in the animals’ skin after receiving the ePatch shot.
Ongoing research is focused on refining the technology further as it progresses along the path towards commercialization. The technology also needs to be validated in human trials before it can be launched for widespread clinical use.
Ultimately, Bhamla says that focusing on simple, cost-effective technologies is a critical part of democratizing access to next-generation healthcare solutions. “We need to think from a cost as well as design perspective about how to simplify and scale up our hardware so these modern interventions can be more equitably dispersed—to reach more underserved and more under-resourced areas of the world.”