Chapter 13 - Skin rejuvenation: Biopolymers applied to UV sunscreens and sheet masks

Abstract

As the largest organ of the body and the most exposed to the environmental surroundings, the skin has increased risk of suffering injuries from harmful substances, which may compromise its degree of hydration, elasticity, and integrity. Among the most relevant elements that can injure the skin, ultraviolet (UV) radiations are responsible for the generation of reactive oxygen species that may undergo intracellular reactions that can seriously damage cells. To protect the skin from UV radiations, sunscreenseither of organic or inorganic natureplay an essential role and hold a significant market share worldwide. To further restore skin hydration, sheet masks have also been proposed. These are aimed to be applied onto the skin for a long time to release their active ingredients further and nurture the skin with, for example, vitamins, proteins, and antioxidants. In this chapter, we address the importance of sunscreens, their classification, and usage in protecting the skin from UVA and UVB rays and discuss the different types of sheet masks commonly in use for skin rejuvenation. The main biopolymers composing these products are also revised, together with the composition and applications of several commercial sheet masks.