The device transfers oxygen from the outside of red blood cells to the inside. Credit: © GettyImages

A new device harnesses the power of light to add oxygen to blood. It could eliminate the need for oxygen therapy in patients with chronic lung disease.

Designed by Rich Gilbert of the Massachusetts Institute of Technology, Cambridge, the gadget transfers oxygen from outside red blood cells to their insides. "The oxygen produced stems from the breakdown of the water in the blood," says Gilbert. "We simply took it from where it is preserved in huge excess."

Chronic lung disease hampers gas exchange in the lung. The resulting low levels of blood oxygen limit exercise and even simple movements like walking. Conventional treatments deliver oxygen to the lungs through tubes.

The MIT device has layers of titanium oxide and indium tin oxide on top of a glass slide. The prototype sits on a table and has blood course over it. A future version could operate like a dialysis machine.

At the flick of a UV-light switch, electrons swap between the two transition metals, pulling oxygen from water molecules and feeding it to the blood's oxygen-carrying protein, haemoglobin. In patients with chronic lung disease, haemoglobin is particularly hungry for oxygen, making it a ready recipient for the molecule.

Tested on bovine blood, UV light increased the fraction of oxygen-containing haemoglobin from 83 per cent to 92 per cent. The effects lasted for more than five hours.

Gilbert isn't satisfied yet with the rate at which his device generates oxygen - less than one-third that of the normal lung - but he is excited about this proof-of-concept. "We have a lot of work to do, but the starting point is solid," he says.