Experimental investigation of red blood cells via digital holographic microscopy

• Applicant: Dr.-Ing. Andrea Winzen
• Subject Area: Fluid Mechanics
• Term: from 2015 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 279132993

Microcirculation plays an important role in the delivery processes of oxygen to the cells and the transport of by-products from the cells. Red blood cells (RBCs) are of special interest in the investigation of blood flow in microcirculation due to the high percentage of these cells on the total blood volume and their relatively large size. RBCs, which are deformed depending on the acting shear rate show different dynamic states and thereby influence the rheological properties of blood including the oxygen transport affecting the regulation of the passing blood volume. To be able to treat pathological alterations in the microvascular system an accurate knowledge of the variation of viscosity and the resulting flow behavior in the microvessels is essential. At present, a target-orientated, low-risk therapy to efficiently regulate the flow in microvessels is impeded by the lack of information about the interaction of viscosity and the specific parameters of RBCs as geometrical shape and dynamic states. The research proposal aims at the measurement of the three-dimensional motion and shape of RBCs in microchannels with a high spatial and temporal resolution via digital holographic microscopy (DHM). To be able to analyze the interaction of the RBCs with the surrounding flow field, simultaneous measurements of the RBCs' motion and the flow field of the carrier fluid are planned. In addition to the axial and radial motion of the RBCs, the shape of the cells will be investigated under various geometric and fluid mechanical boundary conditions. Concerning the fluid mechanical specifications, the flow velocity will be varied in a physiological range, whereas for the geometric constrains, the ratio of the diameter of the RBCs to the diameter of the microchannel itself will be varied to produce a wide spectrum of shear rates that will considerably influence the motion and shape of the RBCs. With the gathered knowledge about the interaction between motion and geometry of erythrocytes, the results of the proposal will contribute to the future development of therapeutic treatment of pathological states in the microvascular system.

• DFG Programme: Research Fellowships
• International Connection: Japan
• Host: Professorin Marie Oshima, Ph.D.