Evaluation of Skin Cell Damage Under UV Exposure with FET Sensors

Abstract

The cell membrane potential can be reflected by the ionic gradient exchange. It has been shown in many cell detection systems to be involved in exploring cell functions. In this research, we have developed a rapid and highly selective array using Field-Effect-Transistor-based sensor to monitor the real time electrical signal change of cell membranes. High sensitivity, low cost, convenient to use and portability are the advantages of our sensor. There is a layer of gelatin immobilized on the sensing site, afterwards utilizing gelatin to capture cells.Around the cell membranes surface is covered with many negative charges, and then the negative ones will attract the positive charges to form electrical-double layer (EDL). According to the charge enhancement, the capacitance generated by the cells will be changed as well as. The change of EDL will also induce a change in the overall capacitance of solution which implies that the gate voltage and drain current gain will also be changed.The current gain has been defined as the difference in absolute drain current before and after the applying the gate voltage.One of the most incredible application of using this novel technology is to detect the cellular conditions. Of note, when the conditions of cells are not good, then the binding of cells and gelatin will be different from the normal ones. From the previous study, binding of cells will cause upward-trend electrical signal. On the other hand, we reasonably speculate there will be a downward-trend occurring during cells suffer from the damage. Many evidences suggest that UV light will directly change or destroy the cytoplasmically located factors, that’s why the biologically fatal dose of Ultraviolet radiation will be used in this experiment because we want to impose the serious damage on the cell membranes and alter the membrane potential of human keratinocyte cells in vitro. Figure 1