Elimination of hazardous chemicals in the process of synthesis, which guarantees the safety of the nanoparticles (NPs) for therapeutic utilization, could be obtained by using the phyto-synthesis method. The present project is a multidimensional survey that aimed to optimize the phyto-synthesis conditions of copper nanoparticles (Cu NPs) using the microwave and ultrasound-assisted methods and facilitate approaching the dilemma of choosing between these two methods by characterizing the final products of each method. Based on the transmission electron microscopy (TEM), the obtained NPs were sub 10 nm in both methods. The optimized NPs were achieved in 5 min using 6 mL of phytoextract at 95 °C in a microwave oven, and amplitude 100% and cycle 0.8 in an ultrasonic processor. In addition to the antibacterial property and molecular wound healing stimulation of Cu NPs, these amorphous nanoscale particles could provide desirable absorption and distribution over the wounds to be suggested as an effective transdermal drug delivery system. The ultrasound-assisted method was the most appropriate way to obtain an amorphous mixture of Cu NPs with a majority of copper oxide while the microwave-assisted method was more suitable for synthesis procedures using plant extracts with heat-sensitive and volatile components.

Prevention of spreading viral respiratory disease, especially in case of a pandemic such as coronavirus disease of 2019 (COVID-19), has been proved impossible without considering obligatory face mask-wearing protocols for both healthy and contaminated populations. The widespread application of face masks for long hours and almost everywhere increases the risks of bacterial growth in the warm and humid environment inside the mask. On the other hand, in the absence of antiviral agents on the surface of the mask, the virus may have a chance to stay alive and be carried to different places or even put the wearers at risk of contamination when touching or disposing the masks. In this article, the antiviral activity and mechanism of action of some of the potent metal and metal oxide nanoparticles in the role of promising virucidal agents have been reviewed, and incorporation of them in an electrospun nanofibrous structure has been considered an applicable method for the fabrication of innovative respiratory protecting materials with upgraded safety levels. Graphical Abstract