2023-05-22 10:21:00
Needle-free delivery
Robert Klatt
Vaccination with compressed gas
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MOF jets can deliver vaccines and drugs through the skin with a gentle burst of pressure. The needle-free treatment is painless and could improve cancer treatment.
Dallas (U.S.A.). The majority of vaccines and biological medicines can currently only be administered by syringe. researchers of University of Texas about Dr. As an alternative, Jeremiah Gassensmith have developed the so-called MOF-Jet, which can administer vaccines and medicines with a gentle pressure pulse through the skin. The needle-free treatment is comparable to contact with a soft toy.
The inspiration for the project came from boredom during the Covid-19 pandemic. Gassensmith had ordered inexpensive components of a compressed air-powered injection system to experiment with during home isolation. Later, when everyone was back on site, he gave these parts to doctoral student Yalini Wijesundara with the task of researching what is possible with them.
Compressed air injectors with liquid flow
Wijesundara had previously researched other compressed air injectors, used as early as the 1960s, that could inject a narrow flow of liquid. She surmised that if these injectors could be modified to fire solids, they could also deliver payloads encapsulated in metal-organic frameworks, or MOFs. These scaffolds are porous, crystalline structures that act like molecular cages and can encapsulate a wide range of materials, including nucleic acids and proteins.
According to the publication in the specialist magazine Chemical Science succeeded in developing the so-called MOF-Jet by combining the compressed air injector with the existing MOF research. This jet can transport powder to cells by literally shooting them in with air.
MOF-Jet uses new delivery method
Air injectors used to be widely used in the military, but they were painful and the injected fluid often splashed back, increasing the risk of spreading other diseases, such as hepatitis B. A modern descendant of these devices is the gene gun, which is mainly used in veterinary medicine and can cost tens of thousands of euros. These devices also shoot biological cargo into cells. In this case, the cargo is attached to the surface of metal microparticles, mostly gold or tungsten. However, as soon as these penetrate the skin, the metal particles remain there and can accelerate the degradation of the biological material.
An alternative method could be to place the cargo in a MOF. Gassensmith’s team had previously worked with the MOF called zeolitic imidazolate framework eight, or ZIF-8.
“Compared to gold, it is inexpensive and protects biological materials such as nucleic acids. It also allows us to store vaccine formulations as a powder at room temperature, eliminating the need for the extremely low temperatures that many liquid vaccines require.”
Biological materials in capsule form
The team encapsulated a range of biological materials in ZIF-8, which helped prevent them from degrading too quickly. To deliver these materials into cells, they used their own modified MOF jet. Wijesundara constructed projectiles for the device, each loaded with a dose of functionalized ZIF-8, and a blast of gas propelled the powdered formulation into the cells. They tested their system and were able to show that the MOF jet delivered a ZIF-8 encapsulated gene to onion cells and a ZIF-8 encapsulated protein to mice.
Wijesundara soon realized that the release of the cargo could be regulated simply by changing the injector’s carrier gas. ZIF-8 is sensitive to acidic environments, and when carbon dioxide reacts with water in cells, carbonic acid is formed, which in turn helps break down the MOF.
“If you bombard it with carbon dioxide, it will release its cargo into the cells faster; if you use normal air it will take four or five days.
This means that the same drug could be released over different time periods without having to change its formulation
Treatment of cancer with MOF-Jet
The team is now using this method to deliver chemotherapy drugs and adjuvants for the potential treatment of melanoma, the most serious form of skin cancer. They believe that because the MOF jet can disperse material over a wide area, it could deliver a cancer drug more evenly into a melanoma than a needle, the current delivery method.
Simply by controlling the carrier gas, they could deliver chemotherapy drugs with a fast or slow release, depending on the patient’s needs. Although research is ongoing, preliminary experiments are showing promising results. Wijesundara and Gassensmith emphasize that the adaptability of their MOF jet could enable a wide range of applications, from veterinary medicine to agriculture to human vaccination or treatment in the future.
Chemical Science, doi: 10.1039/d2sc04982a
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#Vaccines #medicines #administered #painlessly #gas