MOF-Jet: Novel powdered vaccine can be puffed through your skin

Wijesundara took the instructions seriously. Based on her previous research on jet injectors from the 1960s that use compressed gas to inject a narrow stream of fluid, she figured that once the injectors were modified to fire solids, they could deliver the material encased in metal-organic frameworks.

Firing the device is as easy as 'pointing and shooting'

Jet injectors were formerly used in the military but were associated with pain. The fluid also often splashed back, spreading diseases such as Hepatitis B.

Gassensmith’s group previously worked with the MOF called zeolitic-imidazolate framework eight, or ZIF-8. "Compared to gold, it’s cheap and protects biological materials, such as nucleic acids. We can also store vaccine formulations within it as powders at room temperature, which eliminates the need for the extremely cold temperatures many liquid vaccines require," Wijesundara said in a statement.

Wijesundara created 'bullets' for the device, each loaded with a dose of functionalized ZIF-8 and a puff of gas-fired the powdered formulation into cells, which was as simple as "pointing and shooting".

Upon testing, they demonstrated that the MOF-Jet delivered a ZIF-8-encased gene to onion cells and a ZIF-8-encased protein to mice. According to Gassensmith, the blast from the injector feels "like you got hit with a Nerf bullet", which is much less painful than being stuck with a needle.

Currently, the team is using this method to deliver chemotherapeutics and adjuvants as a potential treatment for melanoma. According to the researchers, the MOF-Jet can disperse material over a wide area and, therefore, could distribute cancer therapeutic into a melanoma more evenly than with a needle, which is the current delivery method. Also, by controlling the carrier gas, chemotherapeutics could be delivered within a fast- or slow-release timeframe.

Wijesundara and Gassensmith add that the adaptability of their MOF-Jet permits its use in applications ranging from veterinary medicine to human vaccinations.

The researchers will present their results at the spring meeting of the American Chemical Society.

Study Abstract:

The efficacy and specificity of protein, DNA, and RNA-based drugs make them popular in the clinic; however, these drugs are often delivered via injection, requiring skilled medical personnel, and producing biohazardous waste. Here, we report an approach that allows for their controlled delivery, affording either a burst or slow release without altering the formulation. We show that when encapsulated within zeolitic-imidazolate framework eight (ZIF-8), the biomolecules are stable in powder formulations and can be shot with a low-cost gas-powered “MOF-Jet” into living animal and plant tissues. Additionally, their release profiles can be modulated through judicious selection of the carrier gas used in the MOF-Jet. Our in vitro and in vivo studies reveal that, when CO2 is used, it creates a transient and weakly acidic local environment that causes a near-instantaneous release of the biomolecules through an immediate dissolution of ZIF-8. Conversely, when air is used, ZIF-8 biodegrades slowly, releasing the biomolecules over a week. This is the first example of controlled-biolistic delivery of biomolecules using ZIF-8, which provides a powerful tool for fundamental and applied science research.