Recent Progress in Skin-on-a-Chip Platforms

As the largest organ of the body, the skin acts as a physical barrier for preventing excessive water loss and infection, and the host of many cosmetic and pharmaceutical products. Currently, two-dimensional (2D) cell culture and animal models are extensively used as mainstream platforms to understand skin biology and assess therapeutic drug efficacy. However, 2D cell culture model fails to recapitulate the intricate interactions between cells and the extracellular matrix. The metabolic state of 2D-cultured cells is typically similar, unlike the physiological condition in the body. Also, there is a growing ethical concern over the use of animal studies. Significant advances in microfluidics and tissue engineering have led to the development of three-dimensional (3D) skin-on-a-chip (SOC) technology, which offers a cost-effective alternative to conventional preclinical models for the validation and testing of pharmaceutical and cosmetic products. This review discusses the recent developments in the design of various SOCs, their fabrication strategies and methods for introducing skill cells to the chip, and their respective biomedical applications. Finally, an outlook on current applications, challenges, and future research direction in this field is provided.