CHAPTER 33: Selenium and Antioxidant Microgels

Selenium is a dietary-essential trace element and plays a vital role in human health. Its major biological function is to participate in the construction of the active center of selenoenzymes that serve as antioxidants to regulate the reactive oxygen species level within the cell. Selenium deficiency is associated with a variety of human diseases because a low-selenium status will cause excessive reactive oxygen species to damage the cellular components and induce an intracellular oxidative stress. Recently, the development of artificial antioxidants as a new source to replace natural selenoenzymes has attracted increasing interest for biomedical applications. To date, various strategies including chemical and biological methods have been proposed to design selenoenzyme mimics on different scaffolds, ranging from synthetic compounds to self-assembled composites, based on the mechanism and structure of the well-studied selenoenzyme, glutathione peroxidase. In this chapter, we will focus on the introduction of microgels as a new class of platform to design artificial selenoenzymes and also provide two examples of how to construct advanced antioxidant microgels for intelligent or synergistic catalysis through utilizing their inherent advantages such as water solubility, biocompatibility, multicomponents, and environmental responsiveness.