Scientists are on the trail of a potential antidote for carbon monoxide poisoning, an injected "scavenger" that promises to trap and remove the gas from blood within minutes.

We can't see or smell carbon monoxide as it builds up from car exhaust, a faulty furnace or some other cause. It elbows oxygen out of red blood cells and thus starves the brain and other tissues. Today's only treatment is to get that oxygen replaced in time.

"We have antidotes for cyanide poisoning, for snakebite, but we don't have antidotes for carbon monoxide poisoning and it's the most common poisoning," lamented Dr. Mark Gladwin of the University of Pittsburgh, who is leading new research to develop one.

His team has engineered a protein that can selectively target carbon monoxide, rapidly binding to it so it can't attach instead to the hemoglobin in red blood cells. The compound saved mice from otherwise lethal doses of carbon monoxide, Gladwin reported in the journal Science Translational Medicine.

Gladwin's team started with a hemoglobin-like protein found in the brain called neuroglobin and genetically engineered it to snatch up carbon monoxide. This artificial neuroglobin binds to carbon monoxide about 500 times more tightly than the gas normally can attach to hemoglobin. In lab tests using human red blood cells, the researchers reported the antidote eliminated carbon monoxide many times more rapidly than oxygen, as measured by what's called its half-life — the time it takes for half of it to disappear.

That translated into survival for seven of eight mice exposed to usually lethal carbon monoxide doses. Mouse studies are very preliminary, so more research is needed before the approach could be tried in people.

But there's a need for a quick-to-administer antidote, such as by a paramedic on the scene, said resuscitation specialist Dr. Lance Becker, emergency medicine chairman at Hofstra Northwell School of Medicine, who wasn't involved with the new research.

"I'm cautiously very optimistic," Becker said. "It's very early but this is a very novel sort of approach," and a logical one, he added.