On-Chip Blood Viscometer Towards Point-of-Care Hematological Diagnosis

Blood viscosity is an important hematological parameter which is widely used for the diagnosis of atherosclerosis, thrombosis and stroke. Currently used Couette rheometer drives the blood flow at a certain shear rate and measures the viscosity from the resistance toque towards the rotational shaft. Although effective, conventional rheometer is limited due to the complex configuration and the relatively large sample volume. More important, the rotating components hinder the miniaturization for point-of-care and unattended diagnosis. To address this, a microchip is reported for measuring the blood viscosity from the electrical impedances of the blood flowing inside a microchannel. This microdevice is advantageous over rotational viscometers in less sample consumption, rapid response and simple configuration. Considering the vital role of blood viscosity in cardiovascular disorders, this microchip provides a promising start point for on-chip hematological diagnosis.