BBQ Lighter, Combined with Microneedles, Sparks Breakthrough in COVID-19 Vaccine Delivery

Future vaccine delivery may rely on everyday items like BBQ lighters and microneedles, thanks to the ingenuity of a team of researchers.

Researchers at the Georgia Institute of Technology (Atlanta, GA, USA) and Emory University (Atlanta, GA, USA) have developed and tested an innovative method that may simplify the complexity of delivering COVID-19 and other vaccines through a handheld electroporator. While electroporation is commonly employed in the research lab using short electric pulses to drive molecules into cells, the technique currently requires large, complex, and costly equipment, severely limiting its use for vaccine delivery. The new approach does the job using a novel pen-size device that requires no batteries and can be mass produced at low cost.

The inspiration for the research team’s breakthrough came from an everyday device that people use to start a grill: the electronic barbecue lighter. The team took the innards of a lighter and reengineered them into a tiny spring-latch mechanism. The device creates the same electric field in the skin as the large bulky electroporation machines already in use, but using widely available, low-cost components that require no battery to operate. Pairing the reimagined lighter device with microneedle technology from Georgia Tech’s Laboratory for Drug Delivery has resulted in a new ultra-low-cost electroporation system, or “ePatch.”

Besides the lighter, a key innovation involved tightly spacing the electrodes and using extremely short microneedles. While commonly used in cosmetics to rejuvenate skin and for potential medical applications, microneedles are not generally used as electrodes. Coupling the tiny electroporation pulser with microneedle electrodes made an effective electrical interface with the skin and further reduced the ePatch’s cost and complexity. The microneedle-based system uses voltages similar to conventional electroporation but with pulses that are 10,000 times shorter and using electrodes that penetrate just .01 inch into the skin surface.

To find out if their system could be used with a vaccine to generate an immune response, the researchers tested the delivery system first using a florescent protein to ensure it worked, and to deliver an actual COVID-19 vaccine. They selected an experimental DNA vaccine for COVID-19 as their model. Using this method with the same amount of vaccine, the ePatch induced an almost tenfold improved immune response over intramuscular immunization or intradermal injection without electroporation. It also showed no lasting effects to the mice’s skin, indicating that it is easier to achieve protection. The researchers say the ePatch should also work for mRNA vaccination, which they are currently studying.

Today’s genetic vaccines, whether mRNA or DNA, remain expensive as a global solution because they either require a complicated cold chain and costly manufacturing due to the formulation of lipid nanoparticles for mRNA delivery or they need a sophisticated electroporation device for DNA vaccine delivery. But devising a simpler, cost-effective electroporator that works with the DNA vaccine could dramatically reduce the cost and complexity of vaccinations since it does not require deep-freeze storage of mRNA vaccines, which need frigid temperatures because they contain lipid nanoparticles. The researchers are already looking at ways to refine their system, examining how to optimize the immune response on the skin site and integrating the device into one unit.

“Our goal was to design a method for COVID-19 vaccination that uses a device that is simple, low-cost and manufacturable,” said Dengning Xia, lead author on the study while working as a research scientist at Georgia Tech and currently an associate professor at Sun Yat-sen University in China. “The ePatch is a handheld device the size of a pen, weighing less than two ounces, and requiring no battery or power sources. It operates by simply pushing a button, which makes it very simple to use.”

“We know that COVID-19 won’t be the last pandemic,” said Saad Bhamla, assistant professor in the School of Chemical and Biomolecular Engineering. “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.”

Related Links:
Georgia Institute of Technology 
Emory University