Pills are a clumsy way to deliver drugs. Digestion is a messy process, and making sure the right drug enters the body the right way in enough amounts to matter after digestion is at best inefficient. What if, instead, the drugs could be delivered directly to the part of the body that needs them? Think “topical anesthetic”, only instead of a cotton swab numbing part of a mouth, it’s tiny cannons that use sonic force to fire drugs into organs.
Let me back up a bit. A paper entitled “Acoustic Microcannons: Toward Advanced Microballistics,” published late last month in the journal ACSNano, details the creation of tiny powerful cannons that could some day deliver targeted dosages of medicine into tissues in the body.
The cannon’s barrel itself is 5 micrometers long. To make it, researchers first punctured a membrane (such as pores on skin), and then spraycoated the holes with graphene before adding a coating of gold to further reinforce the tiny boomstick. Gizmodo then describes the tiny cannon firing like this:
Then they had to “load” the cannon with 1-micrometer nanobullets (about the size of the HIV virus) made of silica and encased in a liquid gel. That gel also contained a perfluorocarbon (PFC) as a propellant — because without a propellant, how do you shoot the cannon? PFC starts to vaporize when you blast it with an ultrasonic pulse, and this produces teensy gas bubbles that expand rapidly. It’s that rapid expansion that “fires’ the nanobullets out of the microcannon. Without the PFC, the microcannon just won’t fire.
The cannons haven’t delivered medicine yet, but they did fire deep into tissue, proving themselves as a possible mechanism for drug delivery in the future. As Gizmodo notes, ultrasound has become increasingly attractive for drug delivery as it's pretty non-invasive and can be easily targeted to very specific areas on the body.
It wouldn’t be the first time researchers looked to putting tiny cannons inside people. Last summer, researchers tested small, water-borne railguns, designed to someday travel the bloodstream and, with the aid of an MRI machine, precisely administer drugs.