Self-Transforming Antibiofilm Polyurethane Copolymers with Arginine-Mimetic Cationic Activity for Infection-Resistant Implants
Year: 2026
Type: preprint
Abstract: When bacteria colonize an implant surface, the resulting biofilm renders both antibiotics and the host immune response ineffective.A protective coating on the implant may remain effective initially but lose its function gradually.Here, we show that a segmented polyurethane (PU) copolymer bearing pendant guanidinium groups functions as the active antimicrobial in two material forms: first, as a cationic surface coating; and, upon enzymatic degradation of the polycaprolactone backbone driven by lipase, as cationic colloidal micellar assemblies.Three arginine-mimetic polyurethane (AmPU) compositions (AmPU-H13/H37/H56) with varied hydrophilic content (wH = 13, 37, and 56 wt%) and guanidinium density (CGu = 0.44, 0.39, and 0.35 mmol g - 1 ) are designed, synthesized, and applied.The antibacterial performance of the coatings and micelles followed opposite trends; the intermediate composition, AmPU-H37, exhibited strong bactericidal activity in both forms.AmPU-H37 selectively disrupted S. aureus biofilms but was ineffective against E. coli biofilms, consistent with a lipase-dependent mechanism of action.In a mouse subcutaneous infection model, AmPU-H37 reduced the peri-implant bacterial load by 95% (day 3) while the inflammatory thickness decreased from 98 µm to 27 µm.The composition programmed self-transformation of the polyurethane copolymer thus provides an antibiotic-free design strategy for antibiofilm implant interfaces.
Source: ChemRxiv
Author: Haoran Wang
Institution: Beijing University of Chemical Technology
Language: English
Subfield: Applied Microbiology and Biotechnology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: green
Award: G946819344
OpenAlex ID: W7214991050