High-resolution characterization of biologically relevant soft materials
Abstract
The precise regulation of 3-dimensional (3D) sensing tissue functionality is governed by complex cell-cell and cell-extracellular matrix interactions. However, our understanding of these interactions remains limited, which impedes the development of controllable biological sensing systems and technologies. Our objective is to enhance our understanding of how tissues sense and react to physicochemical disturbances, which can lead to tissue adaptation, recovery, or deterioration. One such disturbance is a rapid change in partial oxygen pressure that can occur in extreme environments, such as a sudden elevation change or injury or dysfunction of blood vessels. To study how blood vessels identify variations in oxygen partial pressure and respond through cell-cell and cell-matrix interactions, we use oxygen-controllable hydrogel systems mimicry of the extracellular matrix. To improve our ability to analyze the chemical and physical characteristics of cell-cell and cell-material interactions, we propose to acquire a Fourier-transform infrared (FTIR) spectroscopy microscope and a dynamic light scattering (DLS) instrument. By combining the use of FTIR microscopy and DLS, we can analyze the molecular composition, size, and surface (zeta) potential of extracellular vesicles (EVs; cell-cell interactions), respectively. Additionally, the FTIR microscope enables the spectroscopic analysis of small, micrometer-sized regions on immobilized cells and thin films, providing a visual map of chemistries in situ to characterize cell-matrix interactions. This is achieved through spatially-resolved recording of the characteristic absorbance of molecular vibrations present in the sample. Notably, FTIR imaging is label-free and does not require sample disruption through added dyes or labeling methods for visualization. These new instrumental capabilities will allow for a more comprehensive understanding of functional effects on cells in various conditions, including changes in partial oxygen pressure. The proposed FTIR and DLS capabilities would enable high-resolution materials characterization in the ongoing AFOSR project and of biologically relevant soft materials and drugs in other DoD-funded research at Duke University. Moreover, the FTIR and DLS will support various projects directly essential to the DoD research mission. To ensure that the instrumentation is widely accessible, the leadership team includes Dr. Sharon Gerecht, Associate Dean for Research and infrastructure, Pratt School of Engineering; Dr. Stefan Zauscher, Director of Duke Materials Initiative; and Dr. Mark Walters, Director of Shared Materials Instrumentation Facility (SMIF). The FTIR and DLS will be housed in SMIF, a multidisciplinary shared-use facility, and will be available to all Duke University researchers, including undergraduate students, graduate students, and postdocs, as well as to external users from other universities, government laboratories, and the industry.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 05, 2025
- Source ID
- FA95502410056
Entities
People
- Sharon Gerecht
Organizations
- Air Force Office of Scientific Research
- Duke University
- United States Air Force