Recent advancements in the semiconductor fabrication technologies have greatly helped in advancing the understanding of electrochemistry at nano scale (10-9 m). Electrodes are being produced at micro (10-6 m) and nano scale with varied materials, designs and for diverse applications. Better electrochemical sensing and detecting capabilities are achieved with nanoelectrodes in comparison with regular macroelectrodes. Lot of theoretical studies of electrochemistry at these nanoelectrodes have been proposed and developed. Despite the theoretical advancements, little has been done in experimental studies of nanoelectrodes. The progress is majorly impeded by lack of reliable fabrication procedures to produce such nanoelectrodes and test them experimentally.;The main goal of this thesis is to develop a new procedure to fabricate nanoelectrode arrays (NEA) for enhanced electrochemical detection. A large area gold NEA is fabricated using nanosphere lithography. The electrochemical advantages of the nanoelectrodes over macro electrodes such as better mass transport of analytes, independent diffusional domains, and faster chemical reaction rates are studied. The dimensions of the electrode are optimized to get the best possible electrochemical sensing capabilities. The optimized NEA is used as a biological sensor for detecting dopamine, a neurotransmitter, in presence of biological levels of ascorbic acid.;The optimized NEA geometry has shown an excellent ability to differentiate and detect the dopamine in presence of high levels of ascorbic acid. This is attributed to the enhanced mass transport of analytes and faster chemical reaction rates at the surface of the nanoelectrodes. Bare gold macroelectrode of similar exposed area has failed to differentiate the dopamine and ascorbic acid signals
