Measurement of adhesion of bovine endothelial cells on different materials using dielectrophoresis

In this study, the design, fabrication, and characterization of dielectrophoresis based devices for the measurement of adhesion of bovine endothelial cells on different biomaterials are conducted. At the design stage, the finite element analysis software COMSOL is used to determine a better design of the dielectrophoretic electrode. Accordingly, a dielectrophoretic device that contains several micro electrodes for producing unbalanced electric field is fabricated using microelectromechanical fabrication technique. The proposed device is then used for the detection of cell adhesion on polydimethylsiloxane (PDMS) and poly lactide (PLA) substrates. The hydrophilicity measurement results reveal that PLA is more hydrophilic than PDMS. It is inferred that BEC should have better adhesion on PLA than on PDMA. However, the cell detachment results do not fully agree with this inference. It is further suggested that other features of the substrate are more crucial than the hydrophilicity on the adhesion of BEC. Cell detachment experiments demonstrate that the applied electrophoresis can not detach the adhered BECs from a PDMS substrate for a seeding time larger than 4 h. However, the dielectrophoretic force due to a 6 V applied potential is enough to lift those cells having cultured on the PLA for 4 and 6 hr. When the culture time is increased to 8 h, cells stretch out apparently and a higher voltage is required to lift and move the cells. The results of cell detachment experiments may suggest that BEC can adhere on PLA stably after 8 h of seeding.