Elaboration of antibacterial polyurethanes for medical devices by a scalable process

Abstract

Medical devices are critical for patient survival in hospitals, yet they represent a leading cause of infections. Polyurethanes (PU), owing to their alternating hard-and soft-segment architecture, enable the fabrication of a broad spectrum of biocompatible materials from highly flexible to rigid and rank among the most prevalent polymers in device manufacturing. Conventional infection prevention relies on incorporating releasable antimicrobial agents into PU matrices; although straightforward to implement, these systems suffer from short-lived efficacy. Surface grafting of active molecules offers an alternative with superior longevity but entails protracted and expensive development. Here, we present a simple, effective, and industrially scalable process for producing antimicrobial PU grades tailored to biomedical applications. By dispersing and co-extruding just 2 wt% of an antibacterial copolymer within a PU matrix, we impart robust antibacterial properties without compromising mechanical performance. We further demonstrate compatibility with essential manufacturing additives, applicability across diverse PU grades, and crucially sustained bioactivity after three months of aqueous immersion or repeated bacterial challenges, all while maintaining non-toxicity. D-SIMS analysis provides the first direct molecular evidence of the antibacterial copolymer's incorporation in PU, revealing homogeneous bulk dispersion with preferential surface enrichment, ideal for contact-killing and unambiguous detection via the ¹²⁷I counterion despite minimal 2 wt% loading. This streamlined approach thus emerges as a compelling alternative to existing strategies, paving the way for safer and more reliable medical devices.