Cell-scale dynamic modeling of membrane interactions with arbitrarily shaped particles

Area of Science:

• Biophysics
• Computational Biology
• Materials Science

Background:

• Modeling cell-scale membrane interactions with complex particle geometries is computationally challenging.
• Existing methods struggle to capture coupled translational and rotational dynamics of arbitrarily shaped particles interacting with deformable membranes.

Purpose of the Study:

• To develop a versatile computational framework for simulating dynamic interactions between lipid vesicles and rigid, arbitrarily shaped particles.
• To investigate the influence of particle shape and mass ratio on membrane deformation and wrapping dynamics.

Main Methods:

• A force-based computational framework using triangulated meshes for vesicle and particle surfaces.
• Langevin dynamics to simulate membrane deformation and rigid-body particle motion.
• Two adhesive interaction models: vertex-to-vertex mapping and vertex-to-surface projection, with the latter showing improved accuracy.

Main Results:

• The framework successfully simulates interactions between various particle shapes (cubical, rod-like, bowl-shaped, tetrahedral) and vesicle shapes (spherical, cigar-shaped, biconcave).
• Lower particle-to-vesicle mass ratios enhance particle reorientation and complete membrane wrapping.
• Higher mass ratios restrict particle reorientation and favor stable partial membrane wrapping.

Conclusions:

• The developed framework provides a generalizable approach for predictive, cell-scale studies of membrane-particle interactions.
• This tool has potential applications in environmental biophysics (e.g., microplastics) and nanomedicine.