A mini review on selenium quantum dots: synthesis and biomedical applications

Abstract

In recent years, the demand for advanced biomedical nanomaterials has seen a noticeable surge. Among the essential trace elements in the human body, selenium has gained recognition for its anti-cancer, antioxidant, and immune regulatory properties. However, traditional selenium-based semiconductor quantum dots (QDs) are often comprised of heavy metal elements that tend to be toxic, thereby limiting their usage in biomedical applications. Fortunately, the advent of elemental selenium quantum dots (SeQDs), a new kind of fluorescent nanomaterial with unique physicochemical properties, has provided a solution to this problem. These SeQDs are known for their low toxicity and good biocompatibility, making them a promising candidate for biomedical applications. In this mini-review, we delve into the synthesis methods of fluorescent SeQDs and the latest progress in their applications in bioimaging, biosensing, and diagnosis treatment. Finally, we identify the major challenges and future prospects in the field of SeQDs.

Selenium Nanoparticles for Antioxidant Activity and Selenium Enrichment in Plants

“…Recent studies have demonstrated that selenium nanoparticles (SeNPs) exhibit fine antioxidant properties, low toxicity, and good biocompatibility. ,− SeNPs have been reported to hold great potential in cultivating selenium-rich plants − and treating ailments such as depression, inflammation, , Alzheimer’s disease, − and nasopharyngeal carcinoma . So far, several methods have been developed to produce SeNPs, including chemical reduction methods, biosynthesis methods, and laser etching methods. ,,− For example, Chen et al used stabilizers like Tremella polysaccharide and mushroom polysaccharide to prepare SeNPs by reducing sodium selenite. , Li et al reported the synthesis of SeNPs by using aquatic bacterium Rahnella aquatilis HX2 to reduce selenite salts .…”

“…13−17 However, the commonly used selenium source, selenite, is a toxic chemical substance that poses significant safety risks in practical applications. 18 Recent studies have demonstrated that selenium nanoparticles (SeNPs) exhibit fine antioxidant properties, low toxicity, and good biocompatibility. 9,19−21 SeNPs have been reported to hold great potential in cultivating selenium-rich plants 14−27 and treating ailments such as depression, 22 inflammation, 23,24 Alzheimer's disease, 25−27 and nasopharyngeal carcinoma.…”

“…This oxidative damage can result in cell death and mutations and pose a severe threat to human health and well-being. , Selenium (Se) is an essential nutrient for humans and animals, as well as a beneficial element for plant growth. It serves as the active site of various enzymes, including glutathione peroxidase, which directly or indirectly participates in the removal of free radicals. − Selenium’s antioxidant capacity is demonstrated in its ability to enhance the activity of superoxide dismutase and glutathione peroxidase, as well as inhibit lipid peroxidation. − Additionally, low concentrations of selenium can promote plant growth, improve plant antioxidant capacity, and enhance the quality of fruits and vegetables. − However, the commonly used selenium source, selenite, is a toxic chemical substance that poses significant safety risks in practical applications …”