Skin-on-a-chip: Microfluidic Device Development Through Photolithography-Based Microfabrication

The main function of human skin is to protect organs by serving as a physiological barrier. Therefore, the skin can be exposed to several chemical substances and biological agents that can cause many skin reactions, such as inflammation, irritation, allergic reactions, and even cancer. For this context, millions of animal experiments have been conducted worldwide. However, these experiments have critical limitations such as ethical and regulatory issues, besides the significant divergence between animal and human physiology. To mitigate these problems, a device was developed to cultivate human cells, hence enabling the miniaturization of a human organ. In the present work, such a model for human skin was developed on a chip that comprises two layers: epidermal and dermal. A porous membrane that allows communication between layers and mimics the biology of the skin separates each layer. The adopted methodology is divided into device modeling, microchannel fabrication, membrane fabrication, and prototype assembly. In this way, a skin-on-a-chip device prototype using a 10 -um-thick PDMS membrane with 8 -umdiameter micro-holes was successfully implemented.