Despite its deadly reputation, carbon monoxide (CO) could save lives and boost health in the future. Chemists at the University of Sheffield in the UK have discovered a way to use targeted small doses of CO to benefit patients who have undergone heart surgery or organ transplants, as well as people suffering from high blood pressure.
Although the gas is lethal in large doses, small amounts can reduce inflammation, widen blood vessels, increase blood flow, prevent unwanted blood clotting, and even suppress the activity of cells that attack transplanted organs. The researchers developed water-soluble molecules which, when swallowed or injected, safely release small amounts of CO inside the body.
CO is produced in the body as part of its own natural defense system. The problem has been finding a safe way of delivering the right dose of CO to a patient. Conventional CO inhalation can run the risk of accidental exposure to high doses. The new CO-releasing molecules (CO-RMs) dissolve in water, so they can be made available in an easy-to-ingest liquid that quickly passes into the bloodstream. The CO-RMs consist of carbonyls of metals such as ruthenium, iron, and manganese, and can release CO over a period of between 30 minutes and several hours, depending on the particular medical condition.