Rheological analysis of non-Newtonian blood flow using a microfluidic device

Blood is a non-Newtonian fluid carrying various cellular components. Rheological behavior of blood is closely correlated with the concentration and the flow condition of cellular components, primarily red blood cells (RBCs). Blood rheology is an important hematological parameter widely used for diagnosis of atherosclerosis, thrombosis and stroke. Nonetheless, there is a lack of appropriate tools dedicated to measurement of rheological behavior of blood flow under physiological flow conditions. In this work, rheological behavior of blood flow under various flow conditions is examined using a microfluidic device. Electrical behavior of blood is examined using electrical impedance spectroscopy. The results show that the flow condition of blood flowing in vessel-like microfluidic channels can be indicated by electrical impedance measurement, where the blood viscosity can be derived. This work provides a promising method for on-chip hematological assay of blood rheological behavior. The simple configuration and electrical readout of the microfluidic device also hold promise for point-of-care diagnosis and intra-operative monitoring. (C) 2010 Elsevier B.V. All rights reserved.