AVS 50th International Symposium
    Biomaterial Interfaces Tuesday Sessions
       Session BI-TuM

Paper BI-TuM10
Preparation and Characterization of Chemically Patterned Surfaces for Cell-Surface Interaction Studies

Tuesday, November 4, 2003, 11:20 am, Room 307

Session: Cell/Surface Interactions
Presenter: D. Marton, The University of Texas Health Science Center at San Antonio
Authors: D. Marton, The University of Texas Health Science Center at San Antonio
E.A. Sprague, The University of Texas Health Science Center at San Antonio
K. Cho, University of Michigan Medical Center
J.C. Palmaz, The University of Texas Health Science Center at San Antonio
Correspondent: Click to Email
There is significant evidence that surface chemistry plays a major role in the way proteins and living cells interact with biomaterial surfaces. These phenomena could be best studied on surfaces with designed and identifiable chemically different areas. For this purpose we developed surface patterning techniques that combine vacuum deposition (dc sputtering or evaporation) and sputter removal of material. Four types of patterned surfaces were developed. Substrates were made of either pre-treated hydrophilic silicon or hydrophobic Teflon. Two types of specimens were created using each substrate type. The first set of patterned surfaces, called "dot pattern" comprised of carbon, stainless steel and gold dots of nominal 25 micron diameter directly deposited on the clean substrates through a stainless steel mask with a polka-dot type hole arrangement. The second set of patterned surfaces, called "hole pattern" were produced by first depositing a continuous layer of carbon, stainless steel or gold. The specimens were then sputtered through the holes of the mask using 1-2 keV Ar ions until the underlying Teflon or silicon became exposed. Typical film thicknesses were 5-10 nm. All specimens were analyzed to verify the patterning on five areas using ToF-SIMS imaging and some using XPS imaging. Pattern definition depends on mask apposition, and, in the case of insulating specimens, on charging effects. In general, the hole patterns have sharper boundaries than the dots. Using an in vitro cell migration model, human aortic endothelial cells were observed to respond to the different patterns with respect to cell shape and cell migration rate. Pattern dependent protein adherence was also observed.