Viscoelastic particle focusing in human biofluids

Area of Science:

• Biophysics
• Fluid Dynamics
• Biomaterials Science

Background:

• Saliva and blood plasma are critical non-Newtonian viscoelastic biofluids.
• These fluids are essential for transporting particulate matter like food and blood cells.
• The influence of biofluid viscoelasticity on suspended particle dynamics remains largely unexplored.

Purpose of the Study:

• To investigate the effect of biofluid viscoelasticity on particle dynamics in microflows.
• To determine if viscoelastic properties of saliva and blood plasma alter particle behavior.
• To explore the relationship between biofluid composition and particle focusing.

Main Methods:

• Utilized pressure-driven microflows of human saliva and blood plasma.
• Observed the lateral migration and focusing of spherical particles within these biofluids.
• Analyzed particle focusing in varying concentrations of bovine submaxillary mucin solutions.

Main Results:

• Spherical particles laterally migrated and focused along the channel centerline in saliva and plasma microflows.
• Particle focusing patterns differed based on sampling times and donors, indicating composition-dependent viscoelasticity.
• Increased mucin concentration in model solutions led to intensified particle focusing.

Conclusions:

• The viscoelastic properties of human saliva and blood plasma significantly influence particle dynamics in microfluidic systems.
• Biofluid composition directly impacts viscoelasticity, affecting particle focusing.
• Findings enhance understanding of the physiological roles of biofluid viscoelasticity in biological transport.