9.2 Applications of Biomedical Polymers in Skin Ba...
The human skin barrier（Figure 9-1）is divided into anatomic barrier and functional barrier.The outermost structure of the skin is the stratum corneum of the epidermis，which forms a cuticle epidermal permeability barrier to prevent the loss of water and electrolytes.Other protective or barrier effect of epidermis include immune defense，UV protection and protection from oxidative damage.Many patients with inflammatory skin diseases have significant disorders of skin barrier structure and function.The stratum corneum moisture content of the cheek skin lesions decreases，the fat content decreases，and the percutaneous water loss increases.Repeated chronic inflammation leads to the destruction of the patient's skin barrier.Chronic photodamage is an important predisposing factor for aggravating the destruction of the skin barrier.When the skin barrier is damaged，erythema，edema，blisters and pigmention appear after a short period of ultraviolet radiation.Prolonged ultraviolet radiation causes skin thickening，elastic fiber damage，wrinkles and other capacious changes.The skin barrier can be repaired with existing biomedical polymer materials.(https://www.daowen.com)