Microfluidic platforms for hemorheology and coagulation time analysis
Hemorheology investigates blood flow characteristics determined by aggregation, sedimentation, and deformation of erythrocytes as well as blood/plasma viscoelasticity. These hemorheological properties are intricately interdependent. Hence, acquired or hereditary disorders affecting one property (malaria, diabetes, anemia) lead to alterations in other properties. Available techniques lack the ability to measure these properties all-at-once and in physiologically relevant conditions.
Blood coagulation is as essential as a healthy blood flow. This is a body defense mechanism involving the interplay of blood components to stop bleeding. Measurement of coagulation time is critical for individuals who are under the risk of excessive bleeding or thrombus-originated vessel obstruction. Today, these conditions are responsible for around 25 percent of all deaths. Unfortunately, the conventional practice for coagulation monitoring is fixed-interval hospital visits.
In this thesis, I will present novel microfluidic platforms and measurement methods for the analysis of hemorheological properties and coagulation time parameters. The assays are based on optical transmission quantification of erythrocyte aggregation and deformation dynamics inside miniaturized channels under in vivo flow and hematocrit conditions. The measurements require only 50 μl undiluted blood and are completed in less than 5 min. Clinical tests were performed using patient samples in local hospitals. Promising results demonstrate that the presented methods have a potential to initiate routine hemorheology and coagulation time analysis even in resource-poor setting.