Research Overview
Our research employs small-angle scattering (SAS) to study the interactions and behaviors of biomacromolecules in crowded and confined environments. By integrating chemistry, physics, and biology, we seek to understand molecular mechanisms governing biological functions and materials. Our work focuses on fundamental biophysical principles while contributing to biomedical and industrial applications.
Project 1: Protein and Polysaccharide Interactions in Crowded Environments
We investigate the phase behavior of proteins and polysaccharides in biologically
relevant crowded environments. These interactions underlie essential biological processes
in plants such as cell wall expansion and pollen formation. Using SAS, we examine
how molecular crowding influences the conformation, dynamics and interactions of
protein and polysaccharide molecules, providing fundamental insights into biomolecular
organization and interactions in living systems. Additionally, we study the interfacial
behavior of protein and polysaccharide complexes as they undergo phase separation,
revealing key structural and dynamic properties that influence their functional roles
in biological and industrial applications.
(Relevant Publication: The assembly mechanism and mesoscale architecture of protein–polysaccharide complexes formed at the solid–liquid interface. Langmuir, 38(41), 12551-12561.)
Project 2: Protein Phase Separation in Living Cells
Our research explores how various proteins undergo liquid-liquid phase separation
(LLPS) within crowded intracellular environments, forming biomolecular condensates
critical to cellular functions. Understanding how crowding agents affect protein conformations
and interactions will provide molecular-level insights into intracellular organization
and disease-related phase separation phenomena, advancing both fundamental biophysics
and potential biomedical therapies.
(Relevant Publication: Biswas, S., Hecht, A. L., Noble, S. A., Huang, Q., Gillilan, R. E., & Xu, A. Y. (2023). Understanding the impacts of molecular and macromolecular crowding agents on protein–polymer complex coacervates. Biomacromolecules, 24(11), 4771-4782.)
Project 3: Aluminum Adjuvants and Vaccine Development
We study the physicochemical properties of aluminum-based adjuvants, which are essential
components in many vaccines. By characterizing their porosity, hydration states, and
interactions with biomolecules using SAS, we aim to elucidate their mechanism of action
at the molecular level. This knowledge will guide the rational design of more effective
and stable nanoparticle-based adjuvants for next-generation vaccines.
(Relevant Publication: Xu, A. Y., Rinee, K. C., Stemple, C., Castellanos, M. M., Bakshi, K., Krueger, S., & Curtis, J. E. (2022). Counting the water: Characterize the hydration level of aluminum adjuvants using contrast matching small-angle neutron scattering. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 648, 129285.)
Project 4: Dilution-Induced Complex Coacervation for Surface Modification
We explore the use of dilution-induced complex coacervation between micelles and polymers
as a novel surface modification method. By leveraging the self-assembly of oppositely
charged macromolecules, we aim to develop robust, environmentally friendly coatings
for materials such as cotton fabrics. This research combines fundamental studies of
coacervate formation with practical applications in sustainable surface engineering.
(Relevant Publication: Xu, A. Y., Kizilay, E., Madro, S. P., Vadenais, J. Z., McDonald,
K. W., & Dubin, P. L. (2018). Dilution induced coacervation in polyelectrolyte–micelle
and polyelectrolyte–protein systems. Soft Matter, 14(12), 2391-2399.; Biswas, S.,
Melton, L. D., Nelson, A. R., Le Brun, A. P., Heinrich, F., McGillivray, D. J., &
Xu, A. Y. (2022). The assembly mechanism and mesoscale architecture of protein–polysaccharide
complexes formed at the solid–liquid interface. Langmuir, 38(41), 12551-12561.)
Our research integrates cutting-edge SAS techniques with interdisciplinary methodologies to address pressing questions in biological physics and materials science. We actively seek motivated students to join our team and contribute to these exciting projects. If you are interested, please feel free to contact Dr. Xu.