Date of Award
Master of Science (MS)
Department of Chemistry
Jeremy D Driskell
Gold nanoparticles (AuNPs) have been exploited in the various domains of science such as drug delivery, bio-sensing, immunoassays and environmental sensors, due to their optical properties and intriguing surface chemistry. Different scientific procedures have been used to effectively immobilize antibodies onto AuNPs. Although acceptable outcomes have been achieved in the immobilization of antibodies onto AuNPs, the sensitivity of these immobilized antibodies to target antigen or binding sites is limited due to improper orientation of the antibodies. Also, the possibility of nanoparticle aggregation when exposed to proteins limits its biomedical applicability.
There is some evidence that the surface charge of antibodies is responsible for controlling the orientation upon adsorption to AuNPs. Antibodies have ubiquitous lysine residues which are protonated at physiological pH contributing to the total surface charge of the antibody. Chemical modification of antibodies by reacting with acrylic acid N-hydroxysuccinimide ester and thiosuccinimidylpropionate, acroleinate and thiopropionate lysine residues respectively, consequently controlling the surface charge of the antibodies and potentially impacting the orientation upon adsorption to AuNPs.
In this proceeding, novel analytical techniques are utilized to directionally adsorb charge modified antibodies onto citrate capped AuNPs to increase the amount of exposed active site. Dynamic light scattering, fluorescence, nanoparticle tracking analysis and other analytical strategies have been used to study the adsorption dynamics, kinetics, and orientation of these charged modified antibodies on AuNPs. These fundamental investigations to elucidate the mechanism of protein-AuNP adsorption will lead to optimized bioconjugates that are necessary to realize the full potential of AuNP-enabled bio-nanotechnologies.
Okyem, Samuel, "Adsorption Behavior of Chemically / Charged Modified Antibodies on Gold Nanoparticles" (2020). Theses and Dissertations. 1303.