Nano-Hitchhikers (IMAGE) Society for Experimental Biology and Medicine Caption 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 Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.