Seminar: Evaluating physical properties and stability of nucleic acid polyelectrolyte micelles

Abstract

Polyelectrolyte complex micelles (PCMs, core-shell nanoparticles formed by complexation of a polyelectrolyte with a hydrophilic charged-neutral block copolymer) offer a solution to the critical problem of delivering therapeutic nucleic acids. Still, few systematic studies have been conducted on how parameters such as charge density, hydrophobicity and nucleic acid structure influence PCM properties, despite evidence that these strongly influence the complexation behavior of polyelectrolyte homopolymers. Using small angle X-ray scattering and electron microscopy, the speaker's group investigates the relationship between the physical properties of oligonucleotide PCMs and chemical properties of the nucleic acids and block copolymers that form them. These observations narrow the design space for optimizing therapeutic PCMs and provide new insights into the rich polymer physics of polyelectrolyte self-assembly.

About the speaker

Alex Marras is a postdoctoral scholar at the Institute for Molecular Engineering at The University of Chicago where he studies polyelectrolyte complexation with biomacromolecules in Professor Matt Tirrell's group. He serves on the User Executive Committee for the Molecular Foundry at Lawrence Berkeley National Laboratory and is the co-chair for the Self-Assembled Biomaterials session at the 2019 American Institute of Chemical Engineers meeting. Marras received his PhD from The Ohio State University working with Carlos Castro in the Department of Mechanical and Aerospace Engineering. His graduate research in structural DNA nanotechnology focused on the development of DNA-based mechanical mechanisms and methods for their rapid actuation. Marras has received multiple awards for his research accomplishments including the Presidential Fellowship at The Ohio State University and Best Poster prize at Foundations of Nanotechnology 2015, which is a preeminent international structural DNA nanotechnology conference. 

Hosted by Prof. Carlos Castro.