Nanotechnology could help overcome a major hurdle in the storage of donor organs.
Scientists have found a way to re-warm blood vessels and heart valves that have been cryogenically frozen, without causing damage to the tissue.
If this can be scaled up, it would be a major advance in the preservation of donor hearts and lungs, up to two-thirds of which currently have to be discarded. Eliminating this waste could bring an end to waiting lists for these organs within two years.
A team at the University of Minnesota tested samples that had been treated with silica-coated iron nanoparticles and vitrified at -160C - preserving them in a glass-like state.
Radio waves were then used to excite the nanoparticles, enabling the tissue to be defrosted evenly without cracking. The research was published in the journal 'Science Translational Medicine'.