AVS 46th International Symposium
    Biomaterial Interfaces Group Tuesday Sessions
       Session BI-TuP

Paper BI-TuP13
Adhesion of Endothelial Cells to Patterned OTS Surfaces

Tuesday, October 26, 1999, 5:30 pm, Room 4C

Session: Poster Session
Presenter: S.R. Webb, Clemson University
Authors: S.R. Webb, Clemson University
T.B. Boland, Clemson University
D.R. Weinbrenner, Clemson University
Correspondent: Click to Email
Thromboresistance is necessary for a biomaterial in vascular applications to maintain proper function. One approach to thromboresistance is to line the interior wall of artificial vascular grafts with endothelial cells.This study examines the effects of surface chemistry and adhesion of endothelial cell membranes to proteins. Hence, understanding these two factors will facilitate applications to reduce thrombogenesis. Cell response to patterned materials was examined by employing highly organized monolayers of self-assembled octadecyltrichlorosilane (OTS) on a silicon wafers. Pure OTS monolayers are poor substrates for cell growth, most likely because of the denaturing of serum proteins near the surfaces. The OTS surfaces were exposed to an electron beam, which selectively oxidized the organic film, creating a variety of oxygenated species at the surface. The monolayers and the patterned surfaces were analyzed by ellipsometry, water contact angle, electron spectroscopy for chemical analysis (ESCA) and AFM. Bovine heart endothelial cells were cultured. Cells were inoculated at 1 x 106 cfu/mL and cultured in twelve well plates in the presence of pure and patterned OTS surfaces. To insure the cells were not toxic to the OTS surfaces three cytotoxicity test were performed. The first was a live dead assay in which calcein green was used to determine if the cells were viable. The second test was MTS to determine if the cells were proliferating. The last test to determine how cytotoxic the surfaces were to the cell was BCA or total protein test. All three tests proved that the patterned surface was not toxic to the cells. The attachment, spreading and growth of the cells on the surfaces will also be presented. The cell spreading on the etched surfaces suggests that the cells may be able to attach more firmly to the extracellular proteins on the etched pattern. The results from this cell growth study will aid in designing micro-patterned surfaces for cell-based biosensors.