Rheology

Thanks to an NSF-MRI grant we have a DHR-3 rheometer which we use to study the rheology (ie, how materials flow or deform when a force is applied) of colloidal fluids, suspensions of DNA, and other materials.

Team members:

Ryan McGorty

Associate Professor of Physics and Biophysics at USD

Karthik Reddy Peddireddy

Post-doc

Juexin Marfai

Undergraduate Student

Laura Morocho

Undergraduate Student

Makayla Baker

Undergraduate Student

Jack Brady

Undergraduate Student
Alumni

Dennis Terwilliger

Undergraduate Student
Alumni

Ryle Rel

Undergraduate Student
Alumni

Demili Pichay

Undergraduate Student
Alumni

Jack Schwarz

Undergraduate Student
Alumni

Philip Neill

Undergraduate Student
Alumni

Nikhil Sonthalia

Undergraduate Student
Alumni

Anna Krolik

High School Intern
Alumni

Max Liu

High School Intern
Alumni

Publications on topic:

Cooperative Rheological State-Switching of Enzymatically-Driven Composites of Circular Dna And Dextran *Juexin Marfai*, *Ryan McGorty*, Rae M. Robertson-Anderson Published in Advanced Materials, July 2023 (see publication) Research themes: Rheology

Shear-induced vorticity aligned flocs in a temperature responsive colloid-polymer mixture *Ryle Rel*, *Dennis Terwilliger*, *Ryan McGorty* Published in Frontiers in Physics, August 2022 (see publication) Research themes: Colloidal Fluids, Rheology

DNA topology dictates emergent bulk elasticity and hindered macromolecular diffusion in DNA-dextran composites Pawan Khanal, *Karthik R. Peddireddy*, *Juexin Marfai*, *Ryan McGorty*, Rae M. Robertson-Anderson Published in Journal of Rheology, June 2022 (see publication) Research themes: Rheology

Presentations:

Dynamics and rheology of colloidal rod suspensions measured with differential dynamic microscopy *Laura G Morocho*, *Nikhil Sonthalia*, *Ryle R. Rel*, Esther Yang, *Ryan McGorty* Presented at APS March Meeting, March 2024 (see published abstract) Research themes: Differential Dynamic Microscopy, Rheology

The rheology of colloidal suspensions measured as rod-shaped particles emerge and grow *Ryle Rel*, *Ryan McGorty* Presented at APS March Meeting, March 2023 (see published abstract) Research themes: Colloidal Fluids, Rheology

Non-equilibrium viscoelasticity driven by dynamic concatenation of ring DNA *Philip Neill*, *Juexin Marfai*, Cindy Sumair, *Ryan McGorty*, Rae Robertson-Anderson Presented at APS March Meeting, March 2023 (see published abstract) Research themes: Rheology

Dynamic concatenation leads to anomalous transport of ring DNA in concentrated solutions *Juexin Marfai*, *Philip Neill*, *Ryan McGorty*, Rae M. Robertson-Anderson Presented at APS March Meeting, March 2023 (see published abstract) Research themes: Rheology

Time-dependent rheology of enzymatically-active composites of DNA and dextran *Juexin Marfai*, Pawan Khanal, *Philip Neill*, Davide Michieletto, *Ryan McGorty*, Rae M. Robertson-Anderson Presented at ACS Spring Meeting, March 2022 (see published abstract) Research themes: Rheology

Shear-induced anisotropy at the meso- and macro-scales in colloidal gels *Ryan McGorty*, *Ryle R. Rel*, *Dennis Terwilliger* Presented at ACS Spring Meeting, March 2022 (see published abstract) Research themes: Colloidal Fluids, Rheology

Time-dependent rheology of enzymatically-active composites of DNA and dextran *Juexin Marfai*, Pawan Khanal, *Philip Neill*, Davide Michieletto, *Ryan McGorty*, Rae M. Robertson-Anderson Presented at APS March Meeting, March 2022 (see published abstract) Research themes: Rheology

Sheared gels form vorticity-aligned flocs depending on the shape of connected colloidal clusters *Ryle R. Rel*, *Dennis Terwilliger*, *Ryan McGorty* Presented at APS March Meeting, March 2022 (see published abstract) Research themes: Colloidal Fluids, Rheology

Colloidal gels displaying both flow-aligned and vorticity-aligned flocs under shear *Dennis Terwilliger*, *John C. Brady*, *Ryan McGorty* Presented at APS March Meeting, March 2021 (see published abstract) Research themes: Colloidal Fluids, Rheology

Cycling between flow-aligned and vorticity-aligned flocs using temperature-sensitive colloid-polymer mixtures *Dennis Terwilliger*, *Ryan McGorty* Presented at International Congress on Rheology, December 2020 Research themes: Colloidal Fluids, Rheology

Observing phase separation of temperature-responsive colloids under shear *John Brady*, *Ryan McGorty* Presented at APS March Meeting, March 2020 (see published abstract) Research themes: Colloidal Fluids, Rheology