Multiscale modeling of hemolysis during microfiltration.

Area of Science:

• Biophysics
• Computational Biology
• Biomaterials

Background:

• Microfiltration of red blood cells (RBCs) can cause mechanical hemolysis, releasing hemoglobin (Hb).
• Existing computational models often rely on empirical parameters, limiting their predictive power under diverse conditions.
• Understanding RBC sensitivity to mechanical stress is crucial for applications like blood processing and disease diagnostics.

Purpose of the Study:

• To develop and validate a multiscale numerical algorithm for simulating Hb release from RBCs during microfiltration.
• To provide a predictive model for hemolysis that is independent of empirical parameters and operating conditions.
• To link RBC membrane deformation to pore formation and subsequent Hb release.

Main Methods:

• Coupled lattice Boltzmann method, spring-connected network, and immersed boundary method for RBC simulation.
• Incorporation of a sub-cellular damage model derived from molecular dynamics simulations.
• Calculation of the index of hemolysis (IH) based on predicted pore radius and a diffusion equation.

Main Results:

• The algorithm accurately predicts RBC damage and Hb release without empirical parameters.
• Numerical results align well with experimental data for hemolysis under varying filtration pressures and pore sizes.
• The model quantifies RBC pore size at rupture, a parameter not measurable in experiments.

Conclusions:

• The proposed algorithm offers a robust, predictive tool for hemolysis simulation in microfiltration.
• This physics-based approach overcomes limitations of empirical models, enabling accurate predictions across different conditions.
• The study validates the link between RBC mechanical stress, membrane permeabilization, and Hb release.