Cobalt-Directed Assembly of Antibodies onto Metal–Phenolic Networks for Enhanced Particle Targeting
Wenjie Zhang, Quinn A. Besford, Andrew J. Christofferson, Patrick Charchar, Joseph J. Richardson, Aaron Elbourne, Kristian Kempe, Christoph E. Hagemeyer, Matthew R. Field, C. F. McConville, Irene Yarovsky, Frank Caruso
Abstract
The orientation-specific immobilization of antibodies onto nanoparticles, to preserve antibody–antigen recognition, is a key challenge in developing targeted nanomedicines. Herein, we report the targeting ability of metal–phenolic network (MPN)-coated gold nanoparticles with surface-physisorbed antibodies against respective antigens. The MPN coatings were self-assembled from metal ions (FeIII, CoII, CuII, NiII, or ZnII) cross-linked with tannic acid. Upon physisorption of antibodies, all particle systems exhibited enhanced association with target antigens, with CoII systems demonstrating more than 2-fold greater association. These systems contained more metal atoms distributed in a way to specifically interact with antibodies, which were investigated by molecular dynamics simulations. A model antibody fragment crystallizable (Fc) region in solution with CoII-tannic acid complexes revealed that the solvent-exposed CoII can directly coordinate to the histidine-rich portion of the Fc region. This one-pot interaction suggests anchoring of the antibody Fc region to the MPN on nanoparticles, allowing for enhanced targeting.