Blockage effects in the chemotaxis of diffusiophoretic particles

Area of Science:

• Microscale and nanoscale transport phenomena
• Biophysics and intracellular organization

Background:

• Directed motion of colloidal particles within cells is driven by chemical gradients via diffusiophoretic transport.
• Understanding how cellular components influence these gradients is key to intracellular organization.

Purpose of the Study:

• To investigate the impact of blockers (passive or consuming) on chemical gradients and diffusiophoretic particle motion.
• To analyze how blocker size and position affect particle transport dynamics.

Main Methods:

• Analytical solutions and finite element simulations were employed.
• The study modeled the influence of single and multiple blockers on chemical gradients.
• Diffusiophoretic velocity fields were analyzed in relation to blocker geometry.

Main Results:

• A single blocker can create or eliminate stagnation points, significantly altering particle transport.
• The finite radius of a second blocker demonstrably shifts substrate distribution and velocity fields.
• Explicit particle radii are critical for accurate modeling under crowded or consumption-driven conditions.

Conclusions:

• Subtle geometric variations in blockers profoundly affect diffusiophoretic motion.
• Blocking and crowding phenomena are critical determinants of intracellular transport.
• This work provides a more complete picture of transport regulation in complex cellular environments.