Transport, Mixing and Rheology of Blood Suspensions in the Microcirculation
Event details
| Date | 27.05.2025 |
| Hour | 11:00 › 12:00 |
| Speaker | Prof. Manouk Abkarian, Centre de Biologie Structurale, CNRS, Montpellier (F) |
| Location | Online |
| Category | Conferences - Seminars |
| Event Language | English |
BIOENGINEERING SEMINAR
Abstract:
This presentation explores the impact of blood being a dense suspension of deformable red blood cells (RBCs) in three problems associated to the microcirculation.
Abstract:
This presentation explores the impact of blood being a dense suspension of deformable red blood cells (RBCs) in three problems associated to the microcirculation.
Firstly, at the capillary scale, RBCs navigate tiny vessel networks, deforming into various shapes to deliver respiratory gases effectively. The interaction of RBCs with network nodes influences overall blood perfusion. Our experiments reveal that RBC flow through uniform networks shows non-linear transport characteristics with pressure, influenced by RBC volume fraction and network topology. This behavior is linked to the local membrane dynamics of RBCs.
Secondly, the importance of blood mixing at the arterio-venule scale is discussed. Effective mixing in microcirculation is crucial for nutrient and waste transport. In vivo, RBC mixing is limited to their own effective diffusion. However, we realise experiments with fluorescent macromolecules in RBC suspensions and we show that mixing improves with higher flow rates and specific volume fractions, suggesting RBCs aid in maintaining a well-mixed blood state.
Lastly, the shear-thinning property of blood, essential for vascular perfusion, is examined. RBC dynamics under physiological conditions reveal complex morphological transitions under increasing shear stress, challenging the current understanding of shear thinning that RBCs align and elongate in flow. These transitions affect blood rheology and are influenced by pathological changes in plasma composition or RBC properties, impacting blood flow behavior.
Bio:
I am a CNRS Senior Scientist working at the Centre de Biologie Structurale in Montpellier, in the Biophysics and Bioengineering department. I co-lead the "Physics and Mechanics of Biological Systems" team. I am a soft matter physicist with an expertise in colloidal systems and microfluidics. Beyond soft matter, I developed an activity at the physics-biology interface within the Charles Coulomb Laboratory in 2005. Over the next 10 years, my work on blood microcirculation motivated me in 2015 to immerse myself in an environment of biologists at CBS and create my own team working on the physics of blood microcirculation, what I called "HemoPhysics". This theme of research and my geographic mobility has been fruitful and with my colleagues Francesco Pedaci and Ashley Nord, we founded a new team in 2020 dedicated to the study of the link between structure, mechanics and dynamics in different classes of biological systems.
Zoom link for attending remotely: https://epfl.zoom.us/j/68671040989
Instructions for 1st-year Ph.D. students planning to attend this talk, who are under EDBB’s mandatory seminar attendance rule:
IN CASE you cannot attend in-person in the room, please make sure to
- send D. Reinhard a note well ahead of time (ideally before seminar day), informing that you plan to attend the talk online, and, during seminar:
- be signed in on Zoom with a recognizable user name (not any alias making it difficult or impossible to identify you).
Practical information
- Informed public
- Free