Monday, September 11, 2017 at 9:00am
Dr. Arthi Jayaraman
Departments of Chemical and Biomolecular Engineering & Materials Science and Engineering
"Linking Molecular Design to Structure and Thermodynamics in Macromolecular Soft Materials"
We develop molecular models, theory and simulation techniques to connect molecular features of macromolecular materials, specifically polymers, to their morphology and macroscopic properties, thereby guiding synthesis and characterization of these materials for various applications in the energy and biomedical fields.
In the first part of my talk, I will present our work on polymer functionalized nanoparticles containing polymer nanocomposites. The overarching goal of this work has been to control spatial arrangement of nanoparticles in the polymer matrix (i.e. polymer nanocomposite morphology) in order to engineer materials with target mechanical or optical properties. One way to tailor polymer nanocomposite morphology is by functionalizing nanoparticle surfaces with polymers, and systematically tuning the composition, chemistry, molecular weight and grafting density of these grafted polymers. We have developed an integrated self-consistent approach involving Polymer Reference Interaction Site Model (PRISM) theory and molecular simulations to study polymer grafted nanoparticles in polymer matrix, and to understand the effect of monomer chemistry, monomer sequence, and polydispersity, in the polymer functionalization on the effective interactions, and dispersion/assembly of functionalized nanoparticles in a polymer matrix. In this talk, I will present our recent results obtained using these computational techniques that agree with experimental results from our collaborator Prof. R. Krishnamoorti at University of Houston.
In the second part of this talk, I will present our molecular simulation work aimed at designing novel oligonucleic acids (ONAs) with varying backbone chemistries to tune ONA hybridization and melting. Since double stranded DNA (ds-DNA) is the basis of various bio- and nano- technologies, the need for cheaper alternatives and significant synthetic advances have led to the design of DNA mimics with new backbone chemistries (e.g. click nucleic acids, locked nucleic acids). A fundamental understanding of how these backbone modifications in the oligo-nucleic acids impact the hybridization and melting behavior of the double strands is still lacking. We develop new coarse-grained (CG) models and use these CG models in molecular dynamics simulations and well-tempered metadynamics calculations to capture the effects of varying backbone chemistries on the H-bonding between complementary nucleobases and the intra-strand base-base stacking, and ONA hybridization/melting. I will also present our recent results on how conjugation of these novel ONAs with biocompatible polymers (e.g. PEG) impacts the polymer-conjugated ONA hybridization. These polymer-conjugated ONAs will serve as building blocks for thermo-responsive gels and networks in biomaterials. This work is done in collaboration with Prof. C. Bowman and Prof. S. Bryant at UColorado Boulder.
Bio: Arthi Jayaraman received her B.E (Honors) degree in Chemical Engineering from Birla Institute of Technology and Science, Pilani, India in 2000. She received her Ph.D. in Chemical and Biomolecular Engineering from North Carolina State University in 2006, and from 2006-2008 conducted her postdoctoral research in the department of Materials Science and Engineering at University of Illinois-Urbana Champaign. In August 2008 she joined the faculty of the Department of Chemical and Biological Engineering at University of Colorado at Boulder, and held the position of Patten Assistant Professor. In August 2014 she joined the faculty at the University of Delaware as Associate professor of Chemical and Biomolecular Engineering and Materials Science and Engineering. She has been awarded the Saville Lectureship at Princeton University (2016), the AIChE COMSEF division young investigator award (2013), the ACS PMSE division young investigator recognition (2014), University of Colorado Provost Faculty Achievement Award (2013), Department of Energy (DOE) Early Career Research Award (2010), the University of Colorado outstanding undergraduate teaching award (2011) and graduate teaching award (2014) in Chemical and Biological Engineering. Her research expertise lies in development of theory and simulation techniques and application of these techniques to study polymer functionalized nanoparticles and polymer nanocomposites, and to design macromolecular materials for biomedical applications.