Biological Systems Engineering


First Advisor

Nicole Iverson

Date of this Version



Stapleton, J. A., Enhancing Single Walled Carbon Nanotube Deposition for the Study of Extracellular Analytes, University of Nebraska Digital Commons, 2019


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Agricultural & Biological Systems Engineering, Under the Supervision of Professor Nicole M. Iverson. Lincoln, NE: November 2019

Copyright © 2019 Joseph A. Stapleton


Extracellular signaling is a dynamic process responsible for coordinating large scale biological processes. As such, understanding extracellular signaling is important to our determination of normal function and pathophysiological development. High resolution spatial and temporal information are critical to completely understanding these processes. Unfortunately, current methods of detection are lacking in either spatial or temporal resolution of extracellular products, limiting researchers’ ability to understand complex biological processes. A new group of sensors based on fluorescent single walled carbon nanotubes (SWNT) have shown the potential to provide both high quality spatial and temporal resolution for the sensing of analytes. However, while SWNT has already been used extensively as an intracellular probe, it has seldom been used for intercellular monitoring. In the few instances that SWNT has been used to form extracellular sensor arrays the deposition method has relied on electrostatic or non-specific interactions and is not well characterized. Herein a new method of SWNT deposition based on the avidin-biotin bond was developed, where biotin activity was imparted to SWNT via coupling to its DNA wrapping and avidin was covalently immobilized on the surface of a glass slide. The method of SWNT immobilization produced a twofold enhancement in SWNT deposition over the current standard without negatively impacting SWNT spectral properties, distribution, response time, or degradation rates. These results indicate the effectiveness of this method for increasing SWNT deposition and provide a simple pathway for enhancing the deposition of DNA-SWNT complexes.

Advisor: Nicole M. Iverson