ResearchFest 2023

The 33rd Annual Department of Chemistry Research Symposium will be held on Tuesday, August 29th, 2023. Please check back for more information and photos from the event!

2023 Career Panelists:

2023 Student Talks:

Abstract: The development of methods to enable the recovery of metastable high-pressure phases to ambient conditions remains an outstanding challenge in materials science. One route that remains unexplored is the use of shockwaves to rapidly decompress samples, analogous to the temperature quenching methods used to recover metastable high-temperature phases in steel processing. In our research, we use in situ X-ray diffraction to explore the impact that dynamic compression and decompression has on the location of phase boundaries in solid-state systems, with the goal of detecting and quantifying the kinetic effects that influence the phase transformations. We are specifically interested in transition metals, alloys, oxides, and carbides. Despite their structural simplicity, these materials remain poorly understood in terms of how they behave under extreme conditions. For example, there are significant differences between the phases observed under static compression and the phases observed under dynamic compression to the same conditions of pressure and temperature. Quantifying the crystal structure in the dynamic compression regime could inform fundamental understanding of atomic bonding, and could also offer insight into planetary processes such as those in our earth’s interior. To reach these conditions and perform our experiments, we travel to some of the brightest and most powerful light sources in the world including synchrotrons and XFELs, and collaborate with scientists at Lawrence Livermore National Laboratory and SLAC National Accelerator Laboratory. In this talk, I will present results from our study into elemental nickel under shock compression, where our exciting findings point to a higher melting pressure and temperature than expected. 

Abstract: Conjugated polymers spearhead the field of organic electronics on multiple forefronts – flexible displays, health monitoring sensors, and photovoltaics. These polymers must be oxidized or reduced to create a charge carrier (polaron) that is balanced by the dopant counterion — a process termed chemical doping. While necessary for electrical conductivity, this simple chemical process also produces complicated and unpredictable changes; doping alters polymer microstructure, generates additional energetic disorder, and can create localized polarons. A lack of control over these parameters impedes further development. I will share a story of how we are reshaping our understanding of charge transport in conductive polymers by controlling the polaron-counterion distance. Through experiments and numerical simulations, we proved that systems with different structural order and side chain composition exhibit different charge transport properties depending on their polaron-counterion distance. We used a combination of dopingdedoping experiments, kinetic analyses, optical characterization, and X-ray scattering. Our results indicate that polymers with shorter polaron-counterion distances lead to increased dopant-induced effects. Our work shows a need for an integrated molecular design that requires both low intrinsic polymer energetic disorder and extrinsic dopantinduced energetic disorder for efficient charge transport. 

Abstract: Intrinsically disordered proteins (IDPs) frequently drive liquid-liquid phase separation (LLPS) processes that give rise to biomolecular condensates. These membraneless subcellular compartments have been linked to myriad biological functions and various diseases including Alzheimer’s and amyotrophic lateral sclerosis. Working hand-in-hand with theory and experiment, molecular simulations have a central role to play in studying how sequence and structural features of IDPs modulate LLPS. For this, coarse-graining is generally required to access the length and time-scales of IDP phase separation. However, the widely-used Ca-only models treat IDPs as simple polymers and fail to capture their peptide nature. Here, we describe a hybrid resolution (HyRes) protein model with coarse-grained side chains but an atomistic backbone for an accurate description of the backbone and transient secondary structures in LLPS. We show that the GPU version of HyRes is efficient enough for direct simulation of spontaneous phase separation of IDPs. Importantly, it is also accurate enough to capture the effect of single mutations on the LLPS propensity. Using two model systems, namely, GY-23 from pepHBP-1 and the conserved region (CR) from TDP-43, we further illustrate how HyRes simulations help to elucidate the coupling between IDP conformational equilibrium and phase separation. These results suggest that the HyRes model provides an important new tool for understanding the molecular basis of IDP-driven LLPS in various biological processes. 

Abstract: The cell membrane is a complex and heterogenous structure composed chiefly of lipids and proteins which dynamically interact with each other. These transient interactions are very important in maintaining the integrity of the cell membrane and in the formation of signaling platforms which enable signal transduction and cell communication. Unfortunately, due to the fast nature of these interactions, our ability to visualize, quantify and precisely modulate them has been limited. We recently developed a probe called the ‘DNA Zipper’ which may address these hurdles by predictably stabilizing transient membrane interactions. Our DNA probe is anchored onto target membrane lipids or proteins as a FRET pair and can reveal various biophysical properties of the live cell membranes. Since dysregulated membrane structures and interactions are known to play critical roles in various diseases, this probe may also serve as a useful platform to identify new drug molecules which may either induce or inhibit certain interactions. Therefore, we believe our DNA Zipper probe may have a broad range of applications to enhance our understanding of important cell membrane interactions and associated cell signaling processes. 

Poster Session Information:

Award Winners:

33rd Annual Department of Chemistry Research Symposium (ResearchFest 2023) Award Winners 

1. Marvin D. Rausch Lectureship Award for Outstanding Oral Presentation (First Place) - Michael Lu Diaz (DV Lab)

2. Marvin D. Rausch Scholarship Award for Outstanding Poster Presentation Morning Session (First Place) - Ruptanu Banerjee (Martin Group)

3. Dr. Paul Hatheway Terry Endowment Award as first-runner up for Outstanding Oral Presentation (Second Place) Yumeng Zhang (Jianhan Chen Group)

4. William E. McEwen Scholarship Fund Award as a joint second-runner up for Outstanding Oral Presentation (Joint Third Place) – Ahsan Ausaf Ali (You Group)

5. William E. McEwen Scholarship Fund Award as a joint second-runner up for Outstanding Oral Presentation (Joint Third Place) – Kimberly Pereira (Walsh Group)

6. William E. McEwen Award for Outstanding Poster Afternoon Session (First Place) - Daniil Ivanov (Kaltashov Group)

7. William E. McEwen Fellowship Award for Outstanding Poster Morning Session (Joint Second Place)- Cristina-Maria Hirschbiegel (Rotello Group)

8. William E. McEwen Fellowship Award for Outstanding Poster Morning Session (Joint Second Place) $200 - Jithu Krishna (Thai Group)

9. William E. McEwen Fellowship Award for Outstanding Poster Morning Session (Third Place)- Scott Thiel (Walsh Group)

10. William E. McEwen Fellowship Award for Outstanding Poster Afternoon Session (Second Place) - $400 Irina Sagarbarria (Hardy Group)

11. William E. McEwen Fellowship Award for Outstanding Poster Afternoon Session (Third Place) - Theo Prachyathipsakul (Thai Group)

12. Paul Hatheway Terry Endowment Awardfor Outstanding Poster Morning Session (People's Choice) – Nicholas Baker (DuChene Group)

13. Dr. Paul Hatheway Terry Endowment Award for Outstanding Poster Afternoon Session  (People's Choice) -  Gaurav Mitra (Kittilstved Group)

ResearchFest 2023 Photos:

Award photos: