Medical science has come a long way since the dark days when blood letting was a physician's only recourse to treatment.

However, even today's most advanced surgeons still have to deal with bleeding. During an average operation, nearly 50% of the surgeon's time is spent controlling bleeding with a variety of clamps and other instruments.

Soon, though, a more efficient way to control bleeding may be on the way.

Scientists at MIT and Hong Kong University have engineered a liquid containing molecule-sized protein fragments called peptides that, at least in hamsters, can stop bleeding from internal and external wounds in seconds.

Here's how it works. When the liquid is injected onto a wound, salt in the blood causes the peptides to self-assemble into a patch of interwoven fibers that stop all liquids, including blood, from flowing out of and into the body. In experiments on hamsters the patch has been able to stop bleeding within fifteen seconds.

Furthermore, because the patch is clear, surgeons would still be able to see what they're doing after the bleeding stops. They could even continue working right through the patch without disrupting its blood-blocking abilities.

With further testing and development, the researchers believe that the blood-stopping material could drastically cut down on the amount of time surgeons currently spend dealing with internal bleeding. The patch could also be useful to medics on the battlefield tending to fallen soldiers where, of course, time is of the essence.