Coating of Polyetheretherketone Films with Silver Nanoparticles by a Simple Chemical Reduction Method and Their Antibacterial Activity

Abstract

The coating of polymeric substrate polyetheretherketone (PEEK) with silver nanoparticles (AgNPs) was carried out by a wet chemical route at room temperature. The coating process was developed from the Tollens reagent and D-glucose as reducing agent. The resulting composite exhibited antimicrobial activity. The PEEK films were coated with a single layer and two layers of silver nanoparticles in various concentrations. The crystallographic properties of the polymer and the silver nanoparticles were analyzed by X-ray diffraction (XRD). Fourier transform infrared spectra (FTIR) show the interaction between the silver nanoparticles with the polymeric substrate. Transmission electron microscope (TEM) images confirmed the obtaining of metallic nanoparticles with average sizes of 25 nm. It was possible to estimate the amount of silver deposited on PEEK with the help of thermogravimetric analysis. The morphology and shape of the AgNPs uniformly deposited on the PEEK films was ascertained by the techniques of scanning electron microscopy (SEM) and atomic force microscopy (AFM), evidencing the increase in the amount of silver by increasing the concentration of the metal precursor. Finally, the antibacterial activity of the films coated with Ag in Escherichia coli, Serratia marcescens and Bacillus licheniformis was evaluated, evidencing that the concentration of silver is crucial in the cellular replication of the bacteria.