Measurement of viscosity of unadulterated human whole blood using a capillary pressure-driven viscometer

Abstract

This paper presents the experimental work on the measurement of unadulterated human whole blood viscosity using a capillary-based microfluidic viscometer. The viscosity was measured by monitoring the time-varying length and mean advancing velocity of the blood column inside the viscometer. A high-aspect-ratio microfluidic channel is preferred for the device geometrical configuration. Theoretical modeling and numerical algorithms were applied to obtain the blood viscosity over a wide range of shear rates. Power law and Carreau-Yasuda models were used to model the non-Newtonian behavior of the human whole blood. The proposed approach is uniquely applicable for small sample volume (<2µL), and short measurement time (<2 min). A wide range of shear rates (varying from of 71.4s^(−1) to 5492.1s^(−1)) is produced in a single test.