MRI: Acquisition of a Rheometer for Interdisciplinary Material Science Research and Training of Undergraduate Researchers

University Of San Diego, San Diego CA

Investigators

Abstract

This award, from the Major Research Instrumentation program, supports the University of San Diego's acquisition of a rheometer. Rheometers are routinely used to study the flow and deformation of soft materials (for example, gels) as a function of applied force and time. Rheometers measure properties such as viscosity, which is a measure of resistance to flow. For instance, water flows easier than honey, so it has a lower viscosity. Viscoelastic materials are those that exhibit both viscous and elastic characteristics under deformation. The rheometer to be acquired is capable of precisely controlling sample temperature, and it also provides direct microscopic visualization of samples under flow. The rheometer also is equipped with tools to measure the tensile and bending strength of solid materials. This instrument will enable the University of San Diego faculty to conduct cutting-edge research on topics related to the behavior of biopolymers (for example, DNA solutions) and antibacterial materials. The rheometer will be used to provide hands-on training of undergraduates across different disciplines such as bioengineering and physics. The instrument also will enable the development of a new interdisciplinary course on biomaterials. A state-of-the-art rheometer equipped with multiple accessories will accommodate diverse research and teaching needs at the University of San Diego, a primarily undergraduate teaching institution. This instrument will significantly advance four specific projects at the University of San Diego. First, it will be used to answer questions on how fluid-fluid phase separation is influenced by shear. Second, it will measure the mechanical properties of starch hydrogels which are used to deliver antimicrobial agents. Third, it will determine how the rheological properties of seawater are altered by mucous secretions and aggregates of microorganisms. Finally, it will measure the viscoelastic properties of biomaterials including cytoskeletal networks and entangled DNA solutions. These main projects, as well as others at the University of San Diego and at neighboring institutions, will be advanced substantially by this state-of-the-art rheometer. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.