| Multi-Electrode Array (MEA) systems have been widely used as in vitro recording tools to study electrogenic cells and tissues, such as cardiac myocytes (heart muscle cells) and neurons. The primary limitation of a conventional MEA system is its difficulty in accurately tracking and investigating the response of specific, individual neurons in vitro because the cells grow randomly on the surface of the MEA chip. One way to remedy this problem is to implement MEAs capable of supporting patterned neural networks, which control individual neuron growth in predetermined positions on top of electrodes. Development of such a novel MEA chip is critical for better understanding the way in which a neural network functions.;This MEA system should be capable of supporting patterned neural networks in vitro. The unique features of this system are: (1) precise and exclusive positioning of the neural cell bodies in the electrode region, (2) definition of interconnecting pathways among the neurons by using patterned self-assembled monolayers (SAMs) which guide growth, and (3) one-to-one stimulation and recording from each sited neuron. This will be an enabling technology for three major disciplines: in vitro neurotoxicology, neuroscience, and neuropharmacology.;In this thesis, we describe the development of a multi- electrode array (MEA) system to detect electrical activities of patterned neural networks. First, this thesis will give an overview of the progress and the challenges of conventional MEA technologies, as well as basic background information related to this research, such as neurons and neural signals, principle of extracellular recording using a MEA system, cellular membrane and extracellular matrix (ECM), and self assembled monolayer (SAM). Then several cell patterning techniques developed will be discussed for this novel MEA system, including microcontact printing using PDMS/photopatternable silicone stamps, cell patterning with cytophobic gold patterns on silicon/glass substrate, and cell patterning using Molecular Vapor Deposition (MVD) of SAMs and lift-off technique. Then, the development of a unique multi-electrode array (MEA) using the method of cytophobic gold patterns on glass substrate to culture neural networks will be described, as well as an electronic package designed to stimulate and record signals from the MEA, and a software package that automates and simplifies data collection. Finally, spontaneous neural activities were recorded with this system. |
