Inhalers work by injecting a fine dry powder into a person's airways and lungs. But an inhaler's performance can be dramatically reduced if the powder clumps together or sticks to the inside of the device.
This is all too commonly caused by electrostatic charges generated by friction between the powder particles. The behaviour of these charges and the electric fields they create is poorly understood. Now, however, Anglo-Swedish company Astrazeneca thinks it knows how to get rid of them.
The trick, it says, is to place the inhaler in an airtight container and lower the pressure. When the pressure is low enough, ions within the air are accelerated by any electric fields within the inhaler. This causes them to bang into other molecules, creating more ions in a kind of chain reaction. These extra ions then neutralise any excess charge, and the inhaler is able to discharge powder without it sticking or clogging.
Read the full ion accelerating inhaler patent applicationJustin Mullins