Preparation of Polyacrylonitrile-based fibres with chelated Ag ions for antibacterial applications

The need for an excellent antibacterial material that is sufficiently
powerful to never develop bacterial resistance is urgent. In this study, a
series of novel polyacrylonitrile-based fibres with chelated Ag ions
(referred to as Ag-SH-PANF) were prepared by a two-step chemical
modification process: grafting and chelating. The properties of the
as-prepared Ag-SH-PANF were characterised by Fourier-transform infrared
(FT-IR) spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction
(XRD), scanning electron microscopy (SEM), and X-ray photoelectron
spectroscopy (XPS). The antibacterial activities of Ag-SH-PANF were
examined against pathogenic bacteria, and an antibacterial mechanism was
explicated based on the release of Ag ions from the fibres’ surfaces. The
results showed that, although chelation occurred between the Ag ions and
the grafted amino and sulfhydryl groups, Ag-SH-PANF retained its fine
microstructure and thermal stability. Moreover, Ag-SH-PANF displayed
excellent antibacterial ability against pathogenic bacteria as well as
good washing durability. In terms of the antibacterial mechanism, Ag ions
are the main bactericidal agents in the role of catalysts, and are not
consumed in the antibacterial process. Nonetheless, a relatively higher
concentration of Ag ions can accelerate the bactericidal process.