Nanoparticles are promising drug delivery tools, offering the ability to administer drugs directly to a specific part of the body and avoid the awful side effects so often seen with chemotherapeutics.
But there’s a problem. Nanoparticles struggle to get past the immune system’s first line of defense: proteins in the blood serum that tag potential invaders. Because of this, only about 1 percent of nanoparticles reach their intended target.
“No one escapes the wrath of the serum proteins,” said Eden Tanner, a former postdoctoral fellow in bioengineering at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS).
Now, Tanner and a team of researchers led by Samir Mitragotri, the Hiller Professor of Bioengineering and Hansjorg Wyss Professor of Biologically Inspired Engineering at SEAS, have developed an ionic forcefield that prevents proteins from binding to and tagging nanoparticles.
In mouse experiments, nanoparticles coated with the ionic liquid survived significantly longer in the body than uncoated particles and, surprisingly, 50 percent of the nanoparticles made it to the lungs. It’s the first time that ionic liquids have been used to protect nanoparticles in the blood stream.
“The fact that this coating allows the nanoparticles to slip past serum proteins and hitch a ride on red blood cells is really quite amazing because once you are able to fight the immune system effectively, lots of opportunities open up,” said Mitragotri, who is also a core faculty member of Harvard’s Wyss Institute for Biologically Inspired Engineering.
The research is published in Science Advances.
