Laser-based system could deliver drugs painlessly

According to a statement, the system uses an erbium-doped yttrium aluminium garnet (Er:YAG) laser to propel a precise stream of medicine with the correct amount of force.

This type of laser is commonly used by dermatologists, particularly for facial aesthetic treatments, said Jack Yoh, professor of mechanical and aerospace engineering at Seoul National University in South Korea, who developed the device along with his graduate students. Yoh and his team describe the injector in a paper published in the Optical Society’s journal Optics Letters.

The laser is said to be combined with a small adapter that contains the drug to be delivered, in liquid form, plus a chamber containing water that acts as a driving fluid.

A flexible membrane separates these two liquids. Each laser pulse, which lasts just 250 millionths of a second, generates a vapour bubble inside the driving fluid. The pressure of that bubble puts elastic strain on the membrane, causing the drug to be forcefully ejected from a miniature nozzle in a narrow jet at 150 millionths of a metre in diameter.