High-Efficiency Biocidal Solution Based on Radiochemically Synthesized Cu-Au Alloy Nanoparticles

Abstract

The use of nanotechnologies in the applied biomedical sciences can offer a new way to treat infections and disinfect surfaces, materials, and products contaminated with various types of viruses, bacteria, and fungi. The Cu-Au nanoparticles (NPs) were obtained by an eco-friendly method that allowed the obtaining in a one-step process of size controlled, well dispersed, fully reduced, highly stable NPs at very mild conditions, using high energy ionizing radiations. The gamma irradiation was performed in an aqueous system of Cu2+/Au3+/Sodium Dodecyl Sulfate (SDS)/Ethylene Glycol. After irradiation, the change of color to ruby-red was the first indicator for the formation of NPs. Moreover, the UV-Vis spectra showed a maximum absorption peak between 524 and 540 nm, depending on the copper amount. The Cu-Au NPs presented nearly spherical shapes, sizes between 20 and 90 nm, and a zeta potential of about −44 mV indicating a good electrostatic stability. The biocidal properties performed according to various standards applied in the medical area, in dirty conditions, showed a 5 lg reduction for Staphylococcus aureus, Pseudomonas aeruginosa, and Enterococcus hirae, a 5 lg reduction for both enveloped and non-enveloped viruses such as Adenovirus type 5, Murine Norovirus, and human Coronavirus 229E, and a 4 lg reduction for Candida albicans, respectively. Thus, the radiochemically synthesized Cu-Au alloy NPs proved to have high biocide efficiency against the tested bacteria, fungi, and viruses (both encapsulated and non-encapsulated). Therefore, these nanoparticle solutions are suitable to be used as disinfectants in the decontamination of hospital surfaces or public areas characterized by high levels of microbiological contamination.

Plasmonic Au–Cu nanostructures: Synthesis and applications

“…A clear redshift of the LSPR peak from 523 nm to 545 nm was observed when the Cu content was increased from 0% to 48% ( Kim et al, 2014 ). A similar result was reported by Nicula and collaborators ( Lungulescu et al, 2021 ). The LSPR absorption bands of Au–Cu core-shell nanocubes have been precisely controlled from 586 nm to 614 nm with changing edge lengths ( Hsia et al, 2016 ).…”

Phytosynthesis of Biological Active Silver Nanoparticles Using Echinacea purpurea L. Extracts

“…X-ray diffraction (XRD) is a popular analytical technique that can be used for the analysis of both molecular and crystal structures, as well as determination of particle sizes, among other applications [ 28 ].…”

Antiviral effects of coinage metal-based nanomaterials to combat COVID-19 and its variants

“…The virucidal effectiveness of Cu–Au bimetallic NPs was evaluated against murine norovirus, adenovirus 5, poliovirus-1, and coronavirus 229 E and reported excellent results. 141 Mohammad and fellows reported another work to utilize bimetallic Au@Ag core-shell NPs modified by poly (3,4-ethylene dioxythiophene) polystyrene sulfonate and functionalized by multi-wall carbon nanotubes on the glassy carbon electrode for the determination of favipiravir (FDA approved antiviral drug). The findings of the voltammetric nanosensor justified the promising determination of favipiravir in clinical samples due to the high conductivity and large surface area of bimetallic Au–Ag nanocomposites.…”

“…144 Similarly, bimetallic nanomaterials with Au possess additional features of detection and identification, photodynamic and photothermal therapy. 141,142,145 In summation, coinage metal-based bimetallic (Cu–Ag, Cu–Au, and Ag–Au), and trimetallic (Cu–Ag–Au) nanomaterials have the potential to fight against SARS-CoV-2 and variants.…”