Hospital-acquired infections arising from implanted polymeric medical devices continue to pose a significant challenge for medical professionals and patients. Often times, these infections arise from biofilm accumulation on the device, which is difficult to eradicate and usually requires antibiotic treatment and device removal. In response, significant efforts have been made to design functional polymeric devices or coatings that possess antimicrobial or antifouling properties that limit biofilm formation and subsequent infection by inhibiting or eliminating bacteria near the device surface or by limiting the initial attachment of proteins and bacteria. In this Viewpoint, we highlight the magnitude of device-associated infections, the role of biofilm formation in human pathogenesis, and recent advances in antimicrobial and antifouling polymers, as well as current strategies employed in commercial devices for preventing infection.

No abstract

Graphical Abstract Kinetically controlled cross-linking processes produce mechanically distinguishable hydrogels using identical precursor chemistry. The oxime ligation demonstrates tunable reaction kinetics with pH and buffer strength, which induces changes in the structural features of hydrogels and determines their mechanical properties. Small-angle neutron scattering and swelling studies provide insight into how structural properties correlate with mechanical properties for this hydrogel system.

The facile fabrication of antimicrobial fiber mats with surface-attached quaternary ammonium compounds (QACs) as the contact-killing antimicrobials was demonstrated. The entire process was designed to be scaled up to a continuous roll-to-roll (R2R) process using a customized R2R manufacturing platform that combines a multinozzle electrospinning technique to generate homogeneous fiber mats and a wet chemical dipping cycle with UV treatment for post-functionalization. A thiol–ene “click” reaction was used to chemically tether a QAC thiol (QAC-SH) on the surface of electrospun fibers containing an alkene functional handle (allyl-TPU). The control of the electrospinning conditions and fiber morphology was investigated by changing the solution concentrations and the tip-to-collector distance (TD). A critical solution concentration correlated to the onset of chain entanglement was necessary to obtain uniform fiber morphology. Surface functionalization of the covalently attached QAC-SH was quantified by fluorescence spectroscopy and X-ray photoelectron spectroscopy (XPS) following the “click” reactions. Antimicrobial assays demonstrated the rapid (>30% in 15 min) and sustained (1–3-log reduction in 4 and 24 h) contact-killing efficacies of QAC-SH-functionalized fiber mats against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria, further demonstrating the feasibility of implementing the post-functionalization process in a continuous R2R manner.

No abstract