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Date of Award

Winter 12-17-2014

Author's School

College of Arts & Sciences

Author's Department/Program

Biology

Degree Name

Bachelor of Arts

Abstract

Alzheimer’s disease is a progressive neurodegenerative disorder that is characterized by accumulation of amyloid-beta (Aβ) peptide in brain regions with high baseline neuronal activity. Previous studies have shown that synaptic activity regulates Aβ production in the mouse brain. To better understand the underlying mechanism, we developed a micro-immunoelectrode (MIE) to improve our ability to study the temporal relationship between synaptic activity and Aβ generation. Here, I evaluated the effects of different electrode pretreatment techniques, antibody-attachment methods, and solution temperature on the oxidation signal of anti-Aβ40 MIEs. MIEs use voltammetry to measure the oxidation of tyrosine at position 10 of Aβ. The specificity of the electrode is determined by anti-Aβ40 antibodies covalently attached to electrode surface. Electrodes pretreated by applying an electrical field showed an increase in antibody attachment compared to electrodes without any pretreatment. Passive attachment, in which the electrode was incubated in the antibody, resulted in equal amount of antibody attachment with less variability compared to active attachment method (electrical field applied while electrode incubated in antibody solution). As the Aβ solution temperature increased, both the magnitude and variability of tyrosine oxidation current increased. Anti-Aβ40 antibodies with high and medium affinity showed an increase in peak current as Aβ concentration increased, whereas low affinity antibody did not show a consistent increase in peak height corresponding to concentration. These findings have optimized three critical parameters for preparing and using MIEs to detect rapid changes in Aβ levels.

Language

English (en)

Advisor/Committee Chair

John Cirrito

Advisor/Committee Chair's Department

Department of Neurology