UK chemists have made a polymer that could be used to make artificial blood, thanks to the polymer's ability to bind to (and then release) oxygen.

Lance Twyman and Yi Ge at the University of Sheffield made a polymer that contains an iron-centred porphyrin, surrounded by branched polyester chains. The polymer binds reversibly to oxygen, they claim.

Twyman and Ge tested their polymer using UV spectroscopy and found that it could survive at least five oxygenation-deoxygenation cycles. Similar cycles are crucial to the transport of oxygen around the body by haemoglobin.

Making these porphyrin-based polymers has been time-consuming and expensive, said Twyman, but the new method is much shorter, improving the chances of developing blood substitutes.

Twyman said this work represents 'a clear proof of principle demonstrating how simple polymers can be used to reversibly bind oxygen.' Future work will concentrate on making improved versions of these polymers, with 'the potential to be applied as future artificial blood products,' he said.

David Barden