Evaluation of antibacterial activity from phytosynthesized silver nanoparticles against medical devices infected with Staphylococcus spp.

Biofilm formation on the surface of medical devices, such as artificial prosthetics and catheters, are serious challenges to biomedical science. Most conventional methods, such as antibiotic therapy and medical device replacement, have failed because of low efficiency in medical environments. In the present study, we aimed to prevent infection by human pathogens Staphylococcus epidermidis (35984) and Staphylococcus aureus (740), which are resistant to antibiotic therapy. To prevent these infections, phytosynthesized silver nanoparticles (AgNPs) coating was tested.

The AgNPs were synthesized using aqueous extract of Berberis asiatica leaves and were characterized by UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and selected area electron diffraction (SAED). The viable cells of bacteria were counted using a digital colony counter.

AgNPs were 15 nm-35 nm in size and crystallized in a face-centred-cubic structure. Furthermore, the AgNPs coating on glass surfaces were bactericidal.

This study suggested that phytosynthesized AgNPs capped with various biomolecules present in leaf extracts of B. asiatica coated on glass surface prevent S. epidermidis and S. aureus associated infections of medical devices. Thus, coating of phytosynthesized AgNPs on glass surfaces may provide efficient antibacterial treatment of infected medical devices.