Blood Substitute

The term 'blood substitute' is a little misleading since their development so far has concentrated primarily on only the blood's function to carry oxygen to our tissues. A more accurate term for blood substitutes being developed would be either:
Cell-free oxygen carriers
Oxygen therapeutics
Red cell substitutes
Essentially, blood substitutes are fluids which, when injected into the human blood stream, contribute significantly to the transport of oxygen around the body. What constitutes a suitable substitute?
Scientists have identified that an ideal blood substitute should have several key properties. These would ensure that a substitute would be free of all of the problems associated with donated human blood when it is used in transfusion. Such properties include:
Adequate oxygen uptake in the lungs
Adequate oxygen delivery to the tissues
Long circulation time
Non-toxic
Rapidly excreted without causing harm
Stable at room temperature and readily available for use
Easily sterelisable (i.e. easy to ensure absence of pathogens such as viruses)
Cheap to manufacture
Long shelf life and easy to store
Widely applicable (i.e. no need for crossmatching or compatibility testing)
Free of any side effects
There are 3 key advantages to a blood substitute that meets all of these criteria, and it is these that make the prospect of developing an effective substitute very exciting:
Unlike red blood cells, a blood substitute could be sterilised, this would mean the problems of disease spreading would be removed from transfusions.
Problems of human error, (mismatching of blood types) with donated blood would be removed since a substitute would not contain the properties of blood that cause this.
A blood substitute could be stored stably for a long time, which would allow for transport to third world countries or to a battlefield, or site of natural disaster without the need for refrigerators. Effectively there would be trouble free availability of blood.