RUI: Developing Predictive Guidelines to Stabilize Gold Nanoparticles with Peptoids

Santa Clara University, Santa Clara CA

Investigators

Abstract

With the support of the Macromolecular, Supramolecular, and Nanochemistry Program in the Division of Chemistry, Professor Amelia A. Fuller of Santa Clara University will prepare new molecules and investigate their ability to stabilize gold nanoparticles in water. Gold nanoparticles have unique properties that make them important and versatile materials for medical diagnostics, for example. To function in water-rich environments for these applications, gold nanoparticles need to coated with specially tailored molecules. The molecular coatings are designed to prevent nanoparticles from forming insoluble, non-functional aggregates. Professor Fuller and undergraduate research assistants in her laboratory will investigate the use of a class of molecules called peptoids for their capacity to coat gold nanoparticles. Dozens of peptoids with different molecular properties will be synthesized and purified. The ability of each of these to prevent nanoparticle inactivation through aggregation will be measured. The research team will determine the specific molecular features of peptoids that confer optimal stability to the nanoparticles. Undergraduate students who participate in the research will cultivate their technical and problem-solving skills. Many of these students will be engaged through introductory-level coursework that incorporates research training. These experiences will equip a large cross-section of students with proficiencies they need for successful careers in science. Colloidal gold nanoparticles are versatile materials that have found wide-ranging applications that leverage their extraordinarily sensitive optical properties. To function in environmentally and physiologically relevant aqueous conditions, gold nanoparticles must be surface-modified with capping ligands. Ideal capping ligands form a well-packed layer on the nanoparticle surface that solubilizes the nanoparticle in aqueous media and shields the core from the salts and proteins that cause them to agglomerate. In this project, Professor Amelia A. Fuller and her group at Santa Clara University will prepare new capping ligands based on the peptoid (N-substituted glycine) scaffold, and investigate their ability to stabilize gold nanoparticles in water. Sequence-specific peptoids that incorporate a wide diversity of functional groups will be prepared. Their ability to stabilize gold nanoparticles of varied sizes will be evaluated. Ultimately, the Fuller laboratory aim to identify critical molecular features of peptoid capping ligands that confer optimal stability to gold nanoparticles. If successful, this understanding will enable the use of peptoid-capped nanoparticles in a wide variety of sensing and diagnostic applications. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.