“Attachment of polymeric nanoparticles to red blood cells combines the advantages of the long circulating lifetime of the red blood cell, and their abundance, with the robustness of polymeric nanoparticles,” said Mitragotri. “Using red blood cells to extend the circulation time of the particles avoids the need to modify the surface chemistry of the entire particle, which offers the potential to attach chemicals to the exposed surface for targeting applications.”
The researchers say that it may be possible to keep the nanoparticles in circulation for a relatively long time, theoretically up to the circulation lifetime of a red blood cell – which is 120 days – if the binding between particles and the red blood cells is strengthened. The methodology is applicable to drugs that are effective while still attached to a red blood cell, although the researchers say that slow release from the red blood cell surface is also feasible.
Mitragotri says “this mode of prolonging particle circulation has significant implications in drug delivery, potentially leading to new treatments for a broad variety of conditions such as cancer, blood clots and heart disease”. Dr. Steven R. Goodman.
Polymer nanoparticles attach to red blood cells and remain in circulation for prolonged times. Unattached nanoparticles are rapidly cleared by body's immune system. Credit: Image prepared by Mr. Peter Allen, UCSB. Society for Experimental Biology and Medicine