Beyond hemoglobin, there are totally synthetic blood substitutes like perfluorocarbon (PFC), a cheap, inert molecule with an enormous capacity to carry oxygen.
Oxygen Biotherapeutics Reports Successful Completion of FDA Requested Immunocompetency Studies on Oxycyte® Oxygen Biotherapeutics, Inc. , is a development stage biomedical company currently focused on developing its perfluorocarbon-based intravenous oxygen carrier, Oxycyte®, as a treatment for traumatic brain injury , stroke and other conditions where critical tissues are oxygen starved.
June 18, 2013 - Business Wire via Yahoo! Finance