SARS-CoV-2 claimed numerous lives and put nations on high alert. The lack of antiviral medications and the small number of approved vaccines, as well as the recurrence of adverse effects, necessitates the development of novel treatment ways to combat COVID-19. In this context, using databases such as PubMed, Google Scholar, and Science Direct, we gathered information about nanotechnology’s involvement in the prevention, diagnosis and virus-like particle vaccine development. This review revealed that various nanomaterials like gold, polymeric, graphene and poly amino ester with carboxyl group coated magnetic nanoparticles have been explored for the fast detection of SARS-CoV-2. Personal protective equipment fabricated with nanoparticles, such as gloves, masks, clothes, surfactants, and Ag, TiO₂ based disinfectants played an essential role in halting COVID-19 transmission. Nanoparticles are used not only in vaccine delivery, such as lipid nanoparticles mediated transport of mRNA-based Pfizer and Moderna vaccines, but also in the development of vaccine as the virus-like particles elicit an immune response. There are now 18 virus-like particle vaccines in pre-clinical development, with one of them, developed by Novavax, reported being in phase 3 trials. Due to the probability of upcoming COVID-19 waves, and the rise of new diseases, the future relevance of virus-like particles is imperative. Furthermore, psychosocial variables linked to vaccine reluctance constitute a critical problem that must be addressed immediately to avert pandemic.

Nanotechnology is an emerging multidisciplinary field that has the potential to offer solutions to pharmaceutical challenges starting from drug delivery to therapeutic applications. The plant-mediated method is eco-friendly and the most inexpensive of the various techniques used to synthesize nanoparticles (NPs). In this study, silver (Ag) NPs have been successfully synthesized using leaf extract of Catharanthus roseus and Ocimum tenuiflorum. X-ray diffraction revealed an average crystalline size of 19.96 and 21.42 nm for C. roseus and O. tenuiflorum-mediated Ag NPs, respectively. Further, shape, size, and elemental composition were analyzed using a scanning electron microscope, transmission electron microscope (TEM), and energy-dispersive X-ray spectral technique. TEM study revealed spherical/spheroidal-shaped Ag NPs were formed between 10–48 nm with C. roseus and 17–55 nm with O. tenuiflorum. Both synthesized Ag NPs inhibited Escherichia coli and Bacillus subtilis, where the effect was more prominent against E. coli (MIC 3.90 ± 0 µg/mL) with O. tenuiflorum Ag NPs. Mechanistic insights of antibacterial activity were also highlighted, and the activity might be attributed to the diverse mode of action of surface functionalized phytoconstituents and NPs.

Heusler materials validates an extensive range of properties characteristically for the prospective high-tech interests. The extensive tunability of these materials through chemical substitutions as well as structural designs sorts the family explicitly fascinating. Self-consistent density functional theory, based on the full-potential linearized augmented plane wave is employed within the WIEN2k simulation code to investigate the structural, magneto-electronic and thermophysical properties of Co₂PdAl and Co₂AgAl Heusler compounds. The steadiness in P–V plot designates the absence of any structural phase transition from a cubic symmetry structure towards other structural phase. The GGA allows calculating the exchange-correlation energy. The proposed compounds are found stable in a Cu₂MnAl prototype phase state. The cohesive and formation energy calculations approve the thermodynamic stability of compounds. The optimized lattice parameters in the stable Fm-3m phase are 5.90 $\text{Å}$ for Co₂PdAl and 5.97 $\text{Å}$ for Co₂AgAl respectively. At Fermi level, these alloys exhibit 100% spin polarization and display half-metallicity. The charge shearing among the constituents’ atoms is presented through the two-dimensional (2D) electron density plot with unique color contrast. The low anharmonicity possessed by the material is favored by the thermal parameters and compounds is predicted stable at a wider range of pressure and temperatures. GRAPHICAL ABSTRACT