A Microfluidic Method for Simultaneous Assessment of Blood Viscosity and Red Blood Cell Aggregation During Continuous...

Area of Science:

• Biomedical Engineering
• Hemodynamics
• Microfluidics

Background:

• Accurate hemorheological analysis requires simultaneous measurement of blood viscosity and red blood cell (RBC) aggregation.
• Simultaneous measurement is challenging due to flow conditions and RBC sedimentation.
• Existing methods struggle to capture dynamic changes during continuous flow.

Purpose of the Study:

• To develop a microfluidic method for simultaneous measurement of blood viscosity and RBC aggregation index (AI) under continuous flow.
• To investigate the influence of flow rate, hematocrit, and syringe operation on these hemorheological properties.
• To evaluate the method's utility in assessing thermally altered RBCs.

Main Methods:

• A microfluidic device with separate viscosity-sensing and aggregation-sensing channels was designed.
• Continuous blood flow was driven by a syringe pump.
• Systematic investigation of flow rate, hematocrit, suspension medium, and syringe on-off operations.
• Evaluation of thermally exposed RBCs to assess functional alterations.

Main Results:

• Blood viscosity and AI are significantly affected by flow rate, hematocrit, and syringe operation.
• Transient flow interruption increases RBC sedimentation, altering hemorheological properties.
• Thermally exposed RBCs showed reduced aggregation and sedimentation.
• Damaged RBCs had minimal impact on sedimentation at higher temperatures and longer exposure times.

Conclusions:

• The developed microfluidic method enables reliable simultaneous evaluation of blood viscosity and RBC aggregation.
• The method is effective in detecting functional alterations in RBCs under continuous flow conditions.
• This approach offers a valuable tool for hemorheological analysis and RBC research.