For people frightened of needles, US researchers have developed a system driven by compressed gas that can deliver vaccines and biologics into the human body in a relatively painless way.

According to the team from the University of Texas at Dallas, the new injector can have a wide number of applications, from veterinary medicine to agriculture, or someday even human vaccinations or treatments.

They presented their results at the ongoing spring meeting of the American Chemical Society (ACS).

During Covid pandemic, principal investigator Jeremiah Gassensmith bought inexpensive pieces of a compressed gas-powered jet injection system to mess around.

After returning to campus, he handed the pieces over to Yalini Wijesundara, a graduate student in the lab, who had previously researched other jet injectors dating back to the 1960s that use compressed gas to inject a narrow stream of fluid.

Wijesundara figured out that they could deliver cargo encased in metal-organic frameworks, or MOFs.

These frameworks are porous, crystalline structures that act like molecular "cages" to encapsulate a wide variety of materials, including nucleic acids and proteins.

They created "MOF-Jet" to deliver powders to cells by, quite literally, shooting them in with air.

The team placed the cargo inside a MOF known as zeolitic-imidazolate framework eight (ZIF-8). The cargo, they decided, would be in the form of a powder rather than liquid, eliminating the need to store the vaccine at cold temperatures.

To test their system, they delivered a ZIF-8 encased gene to onion cells as well as a ZIF-8 encased protein to mice.

Further the researchers said because the MOF-Jet can disperse material over a wide area, it could also distribute a cancer therapeutic into a melanoma more evenly than with a needle, which is the current delivery method.

And simply by controlling the carrier gas, they could deliver chemotherapeutics with a fast- or slow-release timeframe, depending on a patient's needs.