Micro-PIV measurements of the flow field around cells in flow chamber

The velocity profile around cells in a flow chamber coated with the immobilized protein and the endothelial cells is studied using the micro particle image velocimetry（PIV）. The main purpose is to study the effect of the endothelial cells on the local hydrodynamic environment and the local shear rates above a single polymorphonuclear neutrophil（PMN） and a melanoma cell when they adhere to different immobilized protein substrates. Micro-PIV images are taken in the top-view and the side-view under 10 X and 40 X objective lens and the ensemble correlation method is used to analyze the data. The results show that the endothelial monolayer has changed the patterns of the flow velocity profile of the side-view flow on the chamber bottom, and also increased the wall shear rates. The melanoma cells adhered on the immobilized fibrin disturb the local flow more than those adhered on the immobilized fibrinogen, but one sees no significant difference between the local shear rates above the PMNs adhered on the immobilized fibrinogen and those above the PMNs adhered on the immobilized fibrin.