Date of Completion

Spring 5-10-2014

Thesis Advisor(s)

Mu-Ping Nieh

Honors Major

Chemical Engineering


Biochemical and Biomolecular Engineering | Chemical Engineering | Polymer Science


Alzheimer’s disease, a debilitating neurodegenerative illness, is caused by the irreversible aggregation of beta-amyloid proteins in the brain. In Alzheimer’s brains, the protein can become disfigured, causing it to aggregate into long, insoluble fibers that deposit on brain tissue. Studying the aggregation mechanisms of amyloid proteins can lead to a deeper understanding of the progression of Alzheimer’s disease and possibly point towards a potential cure or treatment for the disease. Heat induced aggregation of insulin provides a model system to study the aggregation of amyloidogenic proteins. This study investigates the early stages of heat induced insulin aggregation using dynamic light scattering in order to assess the aggregation mechanism and the potential for reversal by thermal quenching to room temperature. In order to accomplish this, samples of insulin solution were heated for specific incubation intervals and monitored using dynamic light scattering in the time after removal from heat to study the behavior of insulin after quenching to room temperature. Results indicate that large protein aggregates form after sufficient time at heat, but quenching to room temperature can cause them to dissociate. However, the initial stage in the aggregation mechanism is shown to be an irreversible transformation from monomer to dimer.