PHEMA- PANI coating doped with silver nanoparticles for prevention of catheter-associated urinary tract biofilm infections

Long-term indwelling urinary catheters are associated with complications like infection and encrustation, which have brought patients burdens of health problems. Considering the damages caused by urinary tract infections, development of antibiofilm catheter coatings is a practical way to address this issue. Herein, we developed a PHEMA (poly(2- hydroxyethyl methacrylate))-PANI (polyaniline) based coating for stabilizing silver nanoparticles resulting in a high-performance antibiofilm catheter. For this purpose, silicone catheters were functionalized with OH groups and then 2- hydroxyethyl methacrylate (HEMA) was polymerized on the catheter by atom transfer radical polymerization (ATRP). The OH groups of PHEMA were converted into amine groups by reaction with para-anthranilic acid, and in the next step, PANI was produced by oxidation-reduction polymerization. In order to investigate the synergistic effects of silver nanoparticles on the antibacterial property of polyaniline, Ag nanoparticles were coated on polyaniline. Coated catheters were evaluated at each step using attenuated total reflection-fourier transform infrared (ATR-FTIR), scanning electron microscope (SEM), thermal gravimetric analysis (TGA), and atomic force microscopy (AFM). The water contact angle and consequently the hydrophilicity of the coated catheter have increased from 121˚ for the uncoated catheter to 101˚ for catheter-PHEMA-PANI and 73˚ for the catheter-PHEMA-PANI-Ag. Therefore, a hydrophilic PHEMA-PANI-Ag-coated catheter was developed with excellent thermal stability, antibacterial and antibiofilm properties against Escherichia coli and Pseudomonas aeruginosa during 24 and 48 hours and also improved biocompatibility on L929 fibroblast cells. It is concluded that the PHEMA-PANI-Ag-coated catheter with significant activity against antibiofilm formation is a potential candidate for indwelling urinary catheters and supports further clinical investigations.