Characterization of fibronectin properties by integrated micro-fluidic experiments and fluid-structure interaction...

Area of Science:

• Biophysics
• Cellular Mechanics
• Biomaterials Science

Background:

• Fibronectin (Fn) fibers assemble in the extracellular matrix (ECM) and exhibit force-dependent stretching, altering molecular domain functions.
• Previous research focused on Fn's molecular architecture, neglecting its bulk material behavior at the cellular scale and under physiological conditions.
• Microfluidic techniques offer a platform for studying cell rheology in physiological environments, but quantifying properties remains challenging.

Purpose of the Study:

• To assess the material properties of red blood cells (RBCs) and fibronectin (Fn) fibers.
• To develop and validate a computational framework for analyzing fluid-structure interactions (FSI) involving cells and biomaterials.
• To propose a physical-based constitutive model for Fn fiber behavior and analyze its rate-dependent deformation and separation.

Main Methods:

• A monolithic Lagrangian fluid-structure interaction (FSI) approach was developed within the Optimal Transportation Meshfree (OTM) framework.
• The OTM-FSI method was employed to investigate adherent RBCs interacting with fluid, overcoming limitations of traditional computational tools.
• Numerical predictions were calibrated against experimental measurements to assess material properties.

Main Results:

• The study successfully calibrated numerical predictions to experimental measurements, enabling the assessment of RBC and Fn fiber material properties.
• A novel physical-based constitutive model was proposed to describe the bulk behavior of Fn fibers.
• The rate-dependent deformation and separation of Fn fibers were analyzed.

Conclusions:

• The developed OTM-FSI approach provides a robust and reliable numerical framework for studying cellular mechanics and biomaterial behavior.
• This study enhances the understanding of fibronectin's bulk material properties and its role in the extracellular matrix.
• The findings contribute to the accurate quantification of cellular and material properties in microfluidic experiments under physiological conditions.