Spray technique for bioactive materials promises injection-free vaccinations

The technique could lead to a new era of transdermal medication, including injection-free vaccinations, the researchers said.

The team has developed a new approach to electrospray deposition that better controls the target region within a spray zone and the electrical properties of microscopic particles that are being deposited. The greater command of those two properties means that more of the spray is likely to hit its microscopic target. Their results are detailed in Nature Communications.

In electrospray deposition, manufacturers apply a high voltage to a flowing liquid, converting it into fine particles. Each of those droplets evaporates as it travels to a target area, depositing a solid precipitate from the original solution.

“While many people think of electrospray deposition as an efficient method, applying it normally does not work for targets that are smaller than the spray, such as the microneedle arrays in transdermal patches,” said Jonathan Singer, an associate professor in the Department of Mechanical and Aerospace Engineering in the Rutgers School of Engineering and an author on the study. “Present methods only achieve about 40 per cent efficiency. However, through advanced engineering techniques we’ve developed, we can achieve efficiencies statistically indistinguishable from 100 per cent.”