Medicine could be delivered via a high-speed pressure jet through the skin in a new needleless method developed by scientists which could spell the end of painful injections. The Star Trek-style device, unveiled by scientists yesterday, can be programmed to deliver a range of doses to varying skin depths. The breakthrough will be a welcome relief for those with phobias of needles who may avoid immunisation because of their fears.
In the hit science fiction series Star Trek, the space ship’s medical officer Leonard ‘Bones’ McCoy would treat injuries with a needleless device. Researchers now think they have come up with a similar system which produces a high-velocity jet of drugs to penetrate the skin. The device is said to be a major improvement on some fledgling jet-injection systems that have been developed. The researchers say that among other benefits, the technology may drastically cut the number of accidents among doctors and nurses who accidentally prick themselves with needles.
A needleless device may also help improve compliance among patients who might otherwise avoid the discomfort of regularly injecting themselves with drugs such as insulin. Catherine Hogan, a member of the research team at the Massachusetts Institute of Technology, said: ‘If you are afraid of needles and have to frequently self-inject, compliance can be an issue. ‘We think this kind of technology … gets around some of the phobias that people may have about needles.’ In the last few decades, scientists have developed various alternatives to hypodermic needles. For example, nicotine patches slowly release drugs through the skin. But these patches can only release drug molecules small enough to pass through the skin’s pores, limiting the type of medicine that can be delivered.
Now an MIT team, led by Professor Ian Hunter has engineered a jet-injection system that delivers a range of doses to variable depths in a highly controlled manner. The design is built around a mechanism called a Lorentz-force actuator – a small, powerful magnet surrounded by a coil of wire that’s attached to a piston inside a drug ampoule. When current is applied, it interacts with the magnetic field to produce a force that pushes the piston forward, ejecting the drug at very high pressure and velocity (almost the speed of sound in air) out through the ampoule’s nozzle – an opening as wide as a mosquito’s proboscis.
In tests, the group found that various skin types may require different pressure to deliver adequate volumes of drugs to the desired depth. Ms Hogan said: ‘If I’m breaching a baby’s skin to deliver vaccine, I won’t need as much pressure as I would need to breach my skin. We can tailor the pressure profile to be able to do that, and that’s the beauty of this device.’ The breakthrough is reported in the science journal Medical Engineering and Physics.