Microfluidic chip for the detection of biological toxic effects of polychlorinated biphenyls on neuronal cells

The aim of this study was to develop a microfluidic neuronal cell chip device to monitor the toxic effects of polychlorinated biphenyls (PCBs) on PC-12 neuronal cells. PCBs adversely influence the activities of neuronal cells in the nervous system. In PC-12 cells, the production and secretion of dopamine decreases in response to PCB exposure. The microfluidic device that we developed to measure the amount of dopamine by cyclic voltammetry is composed of a control layer, a fluidic layer, and a gold electrode-patterned glass wafer. The control channel in the control layer functions as a microvalve to control the flow of the fluidic channel in the fluidic layer. The fluidic layer consists of 3 reaction chambers as well as fluidic channels. Three electrodes, including the working electrode, counter electrodes, and a reference electrode, are placed in a fluidic chamber. The electrochemical signals of dopamine, either from a standard dopamine solution or from the culture supernatant from cultured PC-12 cells, were obtained using a fabricated microfluidic neuronal cell chip by cyclic voltammetry. When PCBs were added to cultures of PC-12 cells, the amount of dopamine secreted from the PC-12 cells decreased due to the reduced activity of PC-12 cells. The fabricated neuronal cell chip was capable of detecting the toxic effect of dopamine on neuronal cells at concentrations of 10 microg/L and over. The practicality of the developed microfluidic neuronal cell chip was validated using river water spiked with PCBs.