Antifouling polyurethanes to fight device-related staphylococcal infections: synthesis, characterization, and antibiofilm efficacy

Abstract

In hospital settings, biofilm-based medical device-related infections are considered a threat to patients, the sessile growing bacteria playing a key role in the spreading of healthcare-associated infections. In recent decades, the design of antifouling coatings for medical devices able to prevent microbial adhesiveness has emerged as one of the most promising strategies to face this important issue. In order to obtain suitable antifouling materials, segmented polyurethanes characterized by a hard/soft domain structure, having the same hard domain but a variable soft domain, have been synthesized. The soft domain was constituted by one of the following macrodiols: polypropylenoxide (PPO), polycaprolactide (PCL), and poly-l-lactide (PLA). The effects of the polymer hydrophilicity and the degree of hard/soft domain separation on antifouling properties of the synthesized polyurethanes were investigated. Microbial adherence assays evidenced as the polymers containing PCL or PLA were able to significantly reduce the adhesion of Staphylococcus epidermidis with respect to the PPO-containing polymer.

Antifouling and antimicrobial biomaterials: an overview

“…Compared to glass surfaces, the polymers having PEG/PPO or PEG/PTMO in 1/1 molar ratio significantly reduced the adhesion of S. aureus and Enterococcus faecalis, but not the adhesion of P. aeruginosa (27). In segmented hydrophilic PU, not only polymer hydrophilicity but also the degree of hard/soft domain separation seems to influence antifouling properties (190).…”

Synthesis, Characterization, and Bacterial Fouling-Resistance Properties of Polyethylene Glycol-Grafted Polyurethane Elastomers

“…Specifically, PEG was grafted onto the polymer aromatic hard segments, which, being hydrophobic, were supposed to be the domains that were more susceptible to bacterial colonization. We hypothesized that the reduction in the hard domains' hydrophobicity by PEG grafting could be a potential strategy to confer antifouling features to the polymer without changing the polymer backbone composition, neither in terms of monomer type (aliphatic vs. aromatic) nor in hard/soft segment ratio, which could have had a negative effect on the polymer physico-mechanical properties, as previously reported [42]. The obtained PEG-grafted PUs were fully characterized, to assess the effect of PEG-grafting on the thermal and mechanical properties of the polymer itself.…”

Biofilm-based Healthcare-associated Infections

“…Particularly, the heparin coating of CVCs and dialysis catheters resulted in a signifi cant reduction of catheter-related infections (Abdelkefi et al 2007 ;Jain et al 2009 ). Recently, a heparinlike polyurethane possessing negatively charged sulfate groups has been shown to counteract the adhesion of Staphylococcus epidermidis (Francolini et al 2014 ).…”

“…"Such antifouling technology," usually means using steric hindrance at the molecular level to prevent microorganisms from attaching to the surface of the device or using materials with functional groups on the surface that inhibit the growth of microorganisms. In order to obtain suitable antifouling materials, Francolini et al ( 2014 ) have synthesized the segmented polyurethanes characterized by a hard/soft domain structure, having the same hard domain but a variable soft domain. The soft domain was constituted by one of the following macrodiols: polypropylenoxide (PPO), polycaprolactide (PCL), and poly-l-lactide (PLA).…”