Catheter associated urinary tract infections are common during hospitalization due to the formation of bacterial biofilms on the indwelling device.
In this study, we report an innovative biotechnology-based approach for the covalent functionalization of silicone catheters with antifouling zwitterionic moieties to prevent biofilm formation. Our approach combines the potential bioactivity of a natural phenolics layer biocatalytically conjugated to sulfobetaine-acrylic residues in an enzymatically initiated surface radical polymerization with laccase. To ensure sufficient coating stability in urine, the silicone catheter is plasma-activated. In contrast to industrial chemical methods, the methacrylate-containing zwitterionic monomers are polymerized at pH 5 and 50 °C using as an initiator the phenoxy radicals solely generated by laccase on the phenolics-coated catheter surface. The coated catheters are characterized by X-ray photoelectron spectroscopy (XPS), Fourier transformed infrared (FTIR) analysis, atomic force microscopy (AFM), and colorimetrically. Contact angle and protein adsorption measurements, coupled with in vitro tests with the Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus in static and dynamic conditions, mimicking the operational conditions to be faced by the catheters, demonstrate reduced biofilm formation by about 80% when compared to that of unmodified urinary catheters. The zwitterionic coating did not affect the viability of the human fibroblasts (BJ-5ta) over seven days, corresponding to the extended useful life of urinary catheters.
Written by:
Diaz Blanco C, Ortner A, Dimitrov R, Navarro A, Mendoza E, Tzanov T. Are you the author?
Grup de Biotecnologia Molecular i Industrial, Department of Chemical Engineering, Universitat Politècnica de Catalunya, Rambla Sant Nebridi 22, 08222 Terrassa, Spain.
Reference: ACS Appl Mater Interfaces. 2014 Jul 23;6(14):11385-93.
doi: 10.1021/am501961b
PubMed Abstract
PMID: 24955478