One of red blood cells' remarkable characteristics, among many, is their ability to deform and squish their way through blood vessels -- even blood vessels tinier than they are -- to deliver oxygen throughout the body. Scientists believe this flexibility contributes to red blood cells' ability to circulate for an average of 120 days.
Now researchers at the University of North Carolina have synthesized red blood cell-sized and -shaped nanoparticles that mimic this flexibility and longevity. The discovery may lead to the development of better methods for delivering drugs, they reported Monday in the Proceedings of the National Academies of Science.
"We believe this study represents a real game changer for the future of nanomedicine," said Joseph DiSimone, the study's co-lead investigator, in a news release. Getting particles to continue circulating in the body for extended periods has been a challenge, he said.
Previous studies had focused on how size, shape and surface characteristics of particles affected their movement through the bloodstream, the team wrote, but flexibility's role is less well understood. To test it out, the researchers built artificial cells out of a gel material with "tunable elasticity" -- that is, the team could control how deformable the cells were.