Zwitterionic Poly(carboxybetaine) Materials for Blood-Contacting Medical Devices and Nanoparticles

Abstract

Nonspecific protein adsorption in complex media is a crucial issue for biological applications. It degrades the performance of surface-based implanted devices and causes nanoparticles to be recognized by the immune system and rapidly eliminated from systemic circulation. The presented work is a compilation of efforts aimed at developing surface coating based on PCB materials for blood-contacting medical devices and nanoparticles. Surfaces with different packing densities were applied for various purposes. An amperometric enzyme glucose sensor based on glucose oxidase, was used to demonstrate the extraordinary performance of a lightly crosslinked PCB hydrogel in whole blood. This hydrogel presents an ultra-low fouling background to maintain a stable long-term response, even in whole blood. In addition, gold nanoparticles were used as a model system to demonstrate that NPs protected by PCB materials with a high packing density elicit an extremely low immune response after repeated injections, along with having prolonged circulation time and low accumulation in organs in vivo. Finally, ligands with only one CB group were developed to prepare thin surface coatings via self-assembled monolayers. The functional ligands are highly resistant to pH changes, as well as nonspecific protein adsorption.