Bimodal Antimicrobial Surfaces of Phytic Acid-Prussian Blue Nanoparticles-Cationic Polymer Networks

Surface modification plays a pivotal role in tailoring the functionalities of a solid material. Introduction of antimicrobial function on material surfaces can provide additional protection against life-threatening bacterial infections. Herein, a simple and universal surface modification method based on surface adhesion and electrostatic interaction of phytic acid (PA) is developed. PA is first functionalized with Prussian blue nanoparticles (PB NPs) via metal chelation and then conjugates with cationic polymers (CPs) through electrostatic interaction. With the aid of surface adherent PA and gravitation effect, the as-formed PA-PB-CP network aggregates are deposited on the solid materials in a substrate-independent manner. Synergistic bactericidal effects of contact-killing induced by the CPs and localized photothermal effect caused by the PB NPs endow the substrates with strong antibacterial performance. Membrane integrity, enzymatic activity, and metabolism function of the bacteria are disturbed in contact with the PA-PB-CP coating under near-infrared (NIR) irradiation. The PA-PB-CP modified biomedical implant surfaces exhibit good biocompatibility and synergistic antibacterial effect under NIR irradiation, and eliminate the adhered bacteria both in vitro and in vivo.

Automated summary

Surface modification is crucial for tailoring the functionalities of solid materials. In this study, a simple and universal surface modification method based on phytic acid (PA) is developed, which introduces antimicrobial function through the adhesion and electrostatic interaction of PA. The modified surfaces exhibit strong antibacterial performance due to the synergistic bactericidal effects of cationic polymers (CPs) and photothermal effect caused by Prussian blue nanoparticles (PB NPs). The PA-PB-CP coating disturbs the membrane integrity, enzymatic activity, and metabolism function of bacteria, leading to the elimination of adhered bacteria.