Extracellular Potential Recording of Patterned Rat Olfactory Bulb Neuronal Network Using Planar Microelectrode Arrays

The olfactory bulb is an important structure in olfactory information processing. Exploring electrophysiological characteristics of dissected olfactory bulb neuron in vitro is helpful to improving the understanding of the mechanism of the olfactory information processing. In this work, a novel neural chip was developed based on the combination of the microelectrode array and patterned microstructures with the advantages of controllable growth of neurons and long time potential recording. Topographical patterning was used to define position of neuron soma and to guide the neurite outgrowth. A cell culture device with micro wells and micro trenches was fabricated in polydimethylsiloxane using soft lithography. The olfactory bulb neurons were cultured on the cell culture device. At day 8 of the in vitro culture, the device with patterned neuronal network was put upside down on the top surface of a commercially available microelectrode array chip. The micro wells were aligned letting neurons sit on the electrodes. Spike signals of neurons were recorded when the neuronal network was subjected to 1 mM-glutamate stimuli. This convenient method by which the olfactory bulb neural chip was fabricated is feasible for extracellular potential recording of patterned neurons, and may be useful in the further studies of olfactory information processing.