Novel Spray Technique Has Potential to Deposit Bioactive Materials With 100% Efficiency

A newfound technique for an electrospray deposit could advance research toward shot-free vaccinations and other transdermal applications of treatments, according to a study recently published in Nature Communications. An electrospray deposit is an industry spray-coating process, whereby a flowing liquid is converted into fine particles that deposit solid precipitates onto a target area.¹

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"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 study author 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, in a press release. "Present methods only achieve about 40% efficiency. However, through advanced engineering techniques we've developed, we can achieve efficiencies statistically indistinguishable from 100%."¹

Traditionally used on medical devices that are implanted into the body, such as stents, defibrillators, and pacemakers, coatings administered via electrospray deposition have the potential to effectively transpose active biologic agents onto smaller devices like transdermal patches.¹

The Rutgers investigators conducted research to determine if the process of using electrospray deposition to create a bioactive coating could be made more efficient, especially given that bioactive materials like vaccines are costly to produce. Electrospray deposition is achieved when a high voltage, or charge, is applied to the flowing liquid. The team decided to alter the charge landscape of the spray region to see if it changed the efficacy of the spray,“which is [already] a well-established method for analytical chemistry,” Singer said in the press release. ^1,2

Through their research, the Rutgers team learned that the newly engineered electrospray deposition technique does not need an accurately positioned spray source, as opposed to inkjet printing and dip coating techniques. In addition, the cost of making the equipment that would be used to mass manufacture the new electrospray deposition is less than the cost of making prior equipment, and it is also easier to design.¹

The team also discovered that the bioactive material used to coat the microneedle arrays was durable. The bioactive material did not decompose or become lower quality following application onto the array, which suggests that electrospray deposition can be used for various types of small applications, and its durability can reduce the cost associated with new materials.²

"Being able to deposit with 100% efficiency means none of the material would be wasted, allowing devices or vaccines to be coated in this way," said first author Sarah Park, a doctoral student at Rutgers in the Department of Materials Science and Engineering, in the press release. "We anticipate that future work will expand the range of compatible materials and the material delivery rate of this high-efficiency approach."¹

References

1. Scientists develop efficient spray technique for bioactive materials. Rutgers University. News Release. August 18, 2023. Accessed August 23, 2023. https://www.sciencedaily.com/releases/2023/08/230818135209.htm
2. Park SH, D’Souza D, Zipkin R, et al. Efficient electrospray deposition of surfaces smaller than the spray plume. Nature Communications 14, 4896 (2023). DOI: 10.1038/s41467-023-40638-7