Team uses tiny particles to mimic blood

February 10, 2011 at 12:00a.m.

McClatchy Newspapers

RALEIGH, N.C.

The quest to develop synthetic blood is advancing through the work of University of North Carolina-Chapel Hill researchers using tiny particles that are not only the same shape, but same flexibility as vital red blood cells.

The team, led by chemistry professor Joseph De- Simone, who invented a technology to mass-produce uniquely shaped nanoparticles, builds on the observation that red blood cells are more pliant when they’re in the youth of their 120-day life cycle.

New, supple red blood cells are able to squeeze through tiny pores and carry oxygen throughout the body. So by mimicking their shape and flexibility, DeSimone hopes to infuse his man-made microdots with oxygen-carrying hemoglobin to create a synthetic lifeline.

“Mechanics are important, and now we have a vehicle that has the same mechanics as red blood cells when young, and that’s the first big step,” DeSimone said. The research, being tested in mice, was reported recently in the journal Proceedings of the National Academy of Sciences.

Developing synthetic blood has long been the pursuit of scientists searching for an abundant and versatile alternative to use in traumas and battlefields. Whole blood has a limited shelf life, needs refrigeration and must be matched to the recipient.

But efforts to develop viable alternatives have been fraught with pitfalls.

The approach taken by DeSimone and his colleagues is different. It capitalizes on the potential of nanoparticles, which are microscopic vehicles that he and other scientists hope can deliver therapies, scavenge harmful particles such as cholesterol or even serve as surrogates for cells in the body.

“Most people have been going smaller to increase the circulation time,” of nanoparticles filled with hemoglobin for synthetic blood, DeSimone said. But he said the secret to the success of red blood cells is their ability to squish and squirt through minute portals.

Re-creating that quality, he said, could produce a particle that encases the hemoglobin to safely deliver oxygen.