Fingerprints of viscoelastic subdiffusion in random environments: Revisiting some experimental data and their...

Area of Science:

• Physics, Biophysics
• Materials Science

Background:

• Subdiffusion of nanoparticles is observed in complex biological environments like cytosol and plasma membranes.
• These environments exhibit viscoelasticity and inherent disorder, leading to complex diffusion patterns.
• Existing theories struggle to fully explain the observed subdiffusive behaviors.

Purpose of the Study:

• To propose and validate a theoretical framework for understanding nanoparticle subdiffusion in disordered, viscoelastic media.
• To demonstrate the efficacy of the viscoelastic subdiffusion approach in rationalizing experimental data.
• To compare the proposed model against previously established theories.

Main Methods:

• Utilizing generalized Langevin dynamics in random potentials to model particle movement.
• Incorporating viscoelastic properties and environmental disorder into the theoretical framework.
• Analyzing and comparing theoretical predictions with published experimental results.

Main Results:

• The viscoelastic subdiffusion approach provides a superior explanation for experimental findings compared to alternative theories.
• The model successfully integrates aspects of fractional Brownian motion and non-Markovian processes.
• Demonstrated that random potentials and viscoelasticity are key factors in subdiffusion.

Conclusions:

• The generalized Langevin dynamics model in random environments offers a robust explanation for nanoparticle subdiffusion.
• This approach reconciles ergodic and non-ergodic features observed in biological systems.
• Highlights the importance of considering both viscoelasticity and disorder for accurate diffusion modeling.