Variable Cross-Section Microfluidic Channel

Simultaneously replicates two WSS patterns

A single channel that generates low oscillatory shear stress at a step mimicking the carotid sinus and high pulsatile shear stress downstream, using a step-induced vortex to reproduce in vivo hemodynamics for endothelial studies.

Li, Yongjiang · Yuan, Jin · Xue, Chundong · Chen, Dong · Qin, Kairong

Biosensors 2025

Advantages

Simultaneously replicates two WSS patterns

Within a single channel, the step emulates the carotid sinus generating low oscillatory shear stress while the downstream uniform section produces high pulsatile shear stress, enabling study of endothelial responses to both patterns without connecting multiple devices.

CFD-optimized geometry

The influence of step height, width ratio, and input flow rate on vortex formation has been clarified through CFD simulations, providing optimal geometry parameters prior to fabrication and reducing trial-and-error.

Applications

• Endothelial mechanobiology studies：Reproduces the low oscillatory shear stress at the carotid sinus in vitro to study the mechanical causes of endothelial dysfunction.
• Atherosclerosis-on-a-chip：Provides physiologically relevant oscillatory shear stress for atherosclerosis-on-a-chip models, mimicking the hemodynamic conditions at plaque-prone sites.
• Vascular co-culture models：Applies both shear stress patterns to vascular co-culture models to observe interactions between endothelial and smooth muscle cells under complex flow.
• WSS sensing applications：The WSS waveforms generated by this chip can serve as calibration signals for shear stress sensors.