1990 Volume 4 Issue 6 Pages 676-680
Completely artificial red blood cell substitute was produced by embedding synthesized heme into bilayers of liposome. Characteristics such as osmolarity, specific gravity and viscosity can be prepared similar to that of human plasma. Oxygen combining capacity of 100ml and 10mM of this material in vitro was 22ml in ambient air. Oxygen carrying capacity of this material was evaluated in 4 dogs. Dogs weighing 8 to 10 kg were intubated and mechanically ventilated with ambient air. From dog 1 to 4, 200ml, 130ml, 600ml and 300ml of blood was shed. Then 160ml, 130ml, 80ml and 300ml of the liposomeheme solution was intravenously injected. Oxygen transport by 1 mM of liposomeheme and 1 litter of cardiac output was from 6.5 to 9.4ml. Oxygen transport by liposomeheme was 8.8% to 19.0% of total oxygen transport, and oxygen consumption from liposomeheme was 10.9% to 36.1% of total oxygen consumption. Thus the liposomeheme combined and released oxygen. The ability of this liposomeheme to load and unload oxygen in vivo fulfills the basic requirment of an oxygen carrier. Moreover, as the liposomeheme is totally artificial and does not contain blood type antigen, this can be prepared disease free and can be infused without checking patients' blood type.
