Significant blood loss is a common consequence of many types of serious injuries or diseases. Therefore, keeping a healthy supply of human blood for transfusion is vital to save millions of lives every year. Current blood supply levels in many parts of the world may not be sufficient to deal with large-scale human catastrophes, and, in less developed regions, the quality of this supply is jeopardized by improperly eliminated infectious agents. Given that the capacity to raise type-specific supply in a short period of time is limited, scientists and health professionals have an ongoing interest in the development of effective and mass-produced blood substitutes. A recent research effort from Chinese scientists may have brought this ambition much closer to reality.
Multiple research centers in Beijing cooperated for the development of an effective oxygen carrier consisting of hemoglobin metalloproteins coated with a layer of polydopamine. Hemoglobin is a component of red blood cells and is directly involved in the distribution of oxygen to the body’s organs. Previous attempts to synthesize an alternative to natural hemoglobin had a limitation: the chemically distinct protein was toxic and formed methemoglobin, which is a very poor oxygen carrier. Now, researchers found that coating the artificial hemoglobin with a polydopamine layer prevents methemoglobin formation. Through in vitro tests, researchers could observe that the polydopamine coating helped preserve oxygen carrying efficiency, and even enhanced the antioxidative properties of the oxygen carrier.
This study has been published in the journal Biomacromolecules from the American Chemical Society. While it is currently cheaper to use donated blood for transfusion purposes, the future holds promise for mass-produced blood substitutes as production costs would decrease progressively at the pace of manufacturing refinements.
An accessible solution for global problems
Polymerized dopamine is formed when certain materials are soaked in a basic pH dopamine solution. This protective layer can form around objects of a huge variety of sizes, and its versatile properties offer tremendous potential for a wide range of medical applications.
Given that blood transfusions may consist only of specific components of blood, developing an effective oxygen carrier substitute would not only ensure supply availability for catastrophic scenarios, but also drastically improve blood supply quality in some southern African countries, where up to 40% of the population carries the HIV virus. Additionally, this solution would eliminate the blood type compatibility issues that haunt donated blood transfusions, dramatically improve shelf life and ease of storage, and even offer benefits for cancer treatment.