The holy grail of the healthcare industry is often said to be the development of artificial blood. Replacement of donated blood for trauma and surgery with a blood substitute could save many lives and improve the lives of those with blood disorders. Many groups have developed haemoglobin based oxygen carriers (HBOCs) which inevitably lead to kidney damage or even complete renal failure. We have developed a HBOC, SpheriSome Hb where the haemoglobin is encapsulated in a fatty acid capsule, in essence generating artificial red blood cells. SpheriSome Hb has now been shown by the NHS to maintain oxygenation and carbon dioxide removal better than autologous blood in ex-vivo porcine kidney models, where the kidney has been shown to function normally and produce urine.