Research Projects

Intrinsically disordered proteins (IDPs) are a unique class of biomolecules characterized by the absence of a stable tertiary structure, which imparts exceptional conformational flexibility and sensitivity to environmental stimuli such as humidity, temperature, and pH. While IDPs have been extensively studied in dilute solutions, their behavior when confined as thin films in crowded environments remains poorly understood, despite their relevance to biological processes and emerging technologies such as functional coatings, biosensors, and biomedical devices. In thin films, IDP molecules experience geometric confinement, interfacial interactions, and molecular crowding, which can significantly alter their ability to swell, reorganize, and undergo hydration- and/or temperature-induced phase transitions compared to their behavior in solution. Understanding these processes is critical for advancing IDP-based biomaterials and realizing their technological potential. This proposal aims to fill this knowledge gap by investigating the swelling kinetics and phase separations of IDP thin films using a multi-scale experimental approach. The scientific objectives of this project are to investigate how intrinsically disordered protein (IDP) thin films respond to environmental stimuli such as humidity and temperature. This includes quantifying their swelling kinetics in real time using high-resolution techniques, and resolving nanoscale changes in film thickness, interfacial structure, and hydration layers during swelling and deswelling cycles. The project also aims to characterize the formation and evolution of phase-separated regions using x-ray scattering techniques while mapping spatial heterogeneity and morphological transitions using optical and confocal microscopy. The central hypothesis is that IDP thin films exhibit sequence-dependent swelling and hydration-driven phase transitions, fundamentally distinct from globular proteins due to their intrinsic disorder, heterogeneous hydration shells. These behaviors are expected to be amplified under strong confinement and in response to environmental stimuli. Mechanistic models will be developed to describe swelling kinetics, water transport, and network dynamics, directly using the experimental data. The project integrates complementary techniques for multi-scale characterization of IDP thin films. Variable Angle Spectroscopic Ellipsometry (VASE) will track real-time changes in film thickness and refractive index, revealing swelling kinetics and equilibrium behavior. X-ray Reflectivity (XRR) will provide high-resolution profiles of film thickness, electron density, and interfacial roughness during hydration cycles. Small-Angle X-ray Scattering (SAXS) will probe the formation and evolution of nanoscale domains and phase-separated regions. Confocal Laser Scanning Microscopy (CLSM) will enable direct visualization of spatial heterogeneity, domain morphology, and dynamic rearrangements at the microscale. Our experiments will use thin films of three representative IDPs, i) regenerated silk fibroin, and the ii) Amyloid-β and α-synuclein (iii) Gliadin (found in wheat gluten) known for their phase separation behavior, and biomedical relevance. This proposed research is the first integrated, multi-scale study of swelling dynamics and phase behavior in IDP thin films. It will bridge the gap between solution-based understanding and the behavior of immobilized IDPs films under environmental conditions. The findings will offer key insights into the physical principles governing hydration-induced transitions in disordered protein materials, guiding the rational design of responsive biomaterials. This knowledge will support the development of coatings, sensors, drug delivery systems, ultimately laying the foundation for next-generation biomaterials with tunable, predictable, and environmentally adaptive properties.