Q1.
Can we create artificial blood that works just as real blood for all patients?
Answer
Not yet — but scientists are working on it, and the difficulty is exactly the one this chapter is about: blood is a colloid with several different jobs, not a single substance you can bottle.
What artificial blood would have to do
| Job done by real blood | Which component does it | How hard it is to copy |
|---|---|---|
| Carry oxygen to every tissue and bring back carbon dioxide | Haemoglobin inside red blood cells | Partly solved — oxygen-carrying substitutes exist |
| Seal a wound by clotting | Platelets and clotting proteins | Very hard |
| Fight infection | White blood cells | Not achieved |
| Carry nutrients, hormones and wastes | Plasma | Partly possible |
Where the science stands. Two approaches are being tried. One uses haemoglobin taken out of red cells and chemically modified so that it can carry oxygen safely on its own. The other uses perfluorocarbon emulsions — colloids in which oxygen dissolves readily and is released to the tissues. Both are already used in some emergencies to buy time, but neither clots, fights infection, or lasts as long as real blood.
Why an artificial substitute would matter so much: it would not need to be matched to a blood group, so it could be given to anyone immediately; it could be stored for long periods without refrigeration, and carried to remote places; and it would carry no risk of transmitting infection. Until then, the answer is the one on page 87 — donate blood. One donation, separated by centrifugation into plasma, platelets, white cells and red cells, can help several patients at once.
Find out: what is the nearest blood bank to your school, and how does it store each separated component? Different components need different temperatures and have very different storage lives.