A numerical study of plasmon-induced enhancement of dipole emission by arrays of silver nanospheres and nanoprisms

Plasmon-induced enhancement of the photoluminescence (PL) intensity of quantum emitters by plasmon nanoparticles (PNPs) is a promising approach for the design and fabrication of PL hybrid materials with improved properties for biosensing and optoelectronics applications. This enhancement can be achieved through careful selection of such parameters as the PNP’s shape, material, size, the type of the medium around them, as well as the excitation and emission wavelengths of the emitter. Here, we simulated the nano-hybrid materials based on arrays of silver nanospheres, nanoprisms, and their combinations, located on polymer films with embedded dipole emitters. For these systems, the Purcell effect, as well as the excitation enhancement, transmittance, and absorption were evaluated. The results show the way to improve the PL properties of thin hybrid films by careful design of their composition using developed models.

Graphene oxide/silver nanoparticle ink formulations rapidly inhibit influenza A virus and OC43 coronavirus infection in vitro

Respiratory tract infections present a significant risk to the human population, both through seasonal circulation and novel introductions with pandemic potential. There is a strong need for antiviral compounds with broad antimicrobial activity that can be coated onto filtration systems and personal protective equipment to augment their ability to remove infectious particles from the environment. Graphene oxide and silver nanoparticles are both materials with documented antimicrobial properties. Here, we tested the in vitro antiviral properties of several graphene oxide–silver nanoparticle composite materials, which were prepared through three different methods: reduction with silver salt, direct addition of silver nanospheres, and direct addition of silver nanospheres to thiolized graphene. These materials were tested over short time scales for their antiviral activity against two enveloped RNA viruses, influenza A virus and OC43 coronavirus, by performing viral plaque assays after exposure of the viruses to each material. It was found that the graphene oxide – silver nanoparticle materials generated by direct addition of the silver nanospheres were able to completely inhibit plaque formation by both viruses within one minute of exposure. Materials generated by the other two methods had varying levels of efficacy against influenza A virus. These studies indicate that graphene oxide-silver nanoparticle composite materials can rapidly neutralize RNA viruses and demonstrate their potential for use in a wide range of applications.Abstract Figure

Antimicrobial and biological effects of polyaniline/polyvinylpyrrolidone nanocomposites loaded silver nanospheres/triangles

Two silver-polyaniline/polyvinylpyrrolidone (Ag-PANI/PVP) nanocomposites were prepared using in situ integration of silver nanoparticles (AgNPs) during oxidative aniline polymerization, accelerated by the presence of PVP, which as well minimized the risk...

Highly uniform silver nanospheres self-assembled monolayers for sensitive quantitative detection of glutathione by SERS

The homeostasis and imbalance of glutathione (GSH), an important antioxidant in organisms, is one of the key signals that reflect the health of organisms. In this paper, a novel SERS...