Polyphenol‐mediated construction of highly stable and bioactive selenium nanoparticles

Abstract Selenium (Se), a well‐known essential element in human health, plays a vital role in regulating metabolism owing to its antioxidative nature. However, organic Se compounds are toxic and cannot be used for biomedical applications. Selenium nanoparticles (SeNPs) exhibit low biological toxicity and high bioavailability; however, they are prone to aggregation and are extremely unstable, thereby diminishing their bioactivity and bioavailability. To overcome these limitations, ultra‐small, highly stable, and bioactive SeNPs were synthesised based on an in‐situ hybridisation strategy by using polyphenol‐grafted‐chitosan (GA‐CS) to control and restrict crystal growth of Se nanoparticles. The resultant GA‐CS@nSe exhibited an average particle size of ∼30 nm and was highly stable in aqueous solutions. In addition, GA‐CS@nSe displayed improved biocompatibility and enhanced antioxidative activity. Taken together, the authors provide a basis for polyphenol‐mediated construction of Se‐based particles with increased bioactivity.