Nanotechnology is the branch of science which deals with particles ranging between 1–100 nm. These particles are called nanoparticles, and they exhibit unique electronic, optical, magnetic, and mechanical properties, which make them different from the bulk material. These properties of nanomaterials help them to find a variety of applications in the biomedical, agricultural, and environmental domains. Cerium oxide nanoparticles have gained a lot of attention as a potential future candidate for ending various kinds of problems by exhibiting redox activity, free radical scavenging property, biofilm inhibition, etc. Synthesis of these nanoparticles can be performed very easily by utilizing chemical or biological methods. But in this review, the focus is laid on the biosynthesis of these nanoparticles; as the biosynthesis method makes the cerium oxide nanoparticle less toxic and compatible with the living tissues, which helps them to find their path as an anticancer, anti-inflammatory and antibacterial agents. The pre-existing reviews have only focused on details relating to properties/applications/synthesis; whereas this review draws attention towards all the aspects in single review covering all the details in depth such as biosynthesis methods and its effect on the living tissues, along with properties, biomedical applications (diagnostic and therapeutic) and future outlook of the cerium oxide nanoparticle.

Nanotechnology is defined as the branch of science dealing with extremely small-sized particles with a size in the range of 1–100 nm, which are termed nanoparticles. Due to the extremely small size of nanoparticles, they display unique electronic and optical properties, which differentiate them from their bulk form. Thus, due to the unique properties of nanoparticles, they play a crucial role in a variety of fields, including the biomedical, environmental, agricultural, and industrial fields. Selenium belongs to Group 16 of the periodic table with an atomic number of 34 and its nanoparticles have been highlighted as a potential material to alleviate several problems due to the formation of biofilms, production of ROS, low redox activity, etc. These nanoparticles can be synthesized through chemical, physical and biological methods. Since existing reviews mainly concentrated on the individual applications of selenium nanoparticles such as in diagnosis and therapeutics, the present review mainly highlights the potential activity of selenium nanoparticles in the biomedical domain, making them a potential theragnostic agent. Specifically, this review will present detailed information on the bioimaging and therapeutic activity, together with the role of selenium nanoparticles in the current scenario of the ongoing pandemic (SARS-CoV-2). It will also focus on procedures for their synthesis and properties that make them potential candidates for applications in various domains. Finally, we provide a detailed future outlook.

Bioinspired metallic nanoparticles (BMN) have revolutionized the biomedical domain and are still developing rapidly. Hence, this review on BMN elaborates the properties, biosynthesis, biomedical applications, and its role in combating the SARS-CoV-2.

Recent Applications of Magnesium Oxide (MgO) Nanoparticles in various domains