IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Biomaterials Wednesday Sessions
       Session BI+NS-WeA

Paper BI+NS-WeA4
Selective Molecular Assembly Patterning - A New Approach to Micro- and Nanochemical Patterning of Surfaces for Biological Applications

Wednesday, October 31, 2001, 3:00 pm, Room 103

Session: Nanobiology
Presenter: R. Michel, Laboratory for Surface Science and Technology, Switzerland
Authors: R. Michel, Laboratory for Surface Science and Technology, Switzerland
J.W. Lussi, Laboratory for Biomedical Engineering, Swiss Federal Institute of Technology, Zurich, Switzerland
I. Reviakine, Laboratory for Surface Science and Technology, Switzerland
M. Textor, Laboratory for Surface Science and Technology, Switzerland
N.D. Spencer, Laboratory for Surface Science and Technology, Switzerland
Correspondent: Click to Email
A novel method for producing chemically patterned surfaces based on selective self-assembly of alkane phosphates on metal oxide surfaces is presented. Standard photolithography is used to create patterns of titanium oxide within a matrix of silicon oxide by successively depositing 40 nm of TiO@sub 2@, 10 nm of SiO@sub 2@ onto a silicon wafer, followed by photoresist application and anisotropic etching. Ordered SAMs of alkane phosphates form on the TiO@sub 2@, but not on the SiO@sub 2@ surfaces by self-assembly. Poly-L-lysine-g-poly(ethylene glycol) (PLL-g-PEG) is used to render the exposed SiO@sub 2@ protein-resistant. X-ray photoelectron spectroscopy and imaging time-of-flight secondary ion mass spectrometry were used to characterize the surfaces. Protein adsorption studies conclusively established that the resulting surfaces presented protein adhesive (the TiO@sub 2@/alkane phosphate SAM region) and non-adhesive (the PLL-g-PEG-coated SiO@sub 2@) areas. This novel Selective Molecular Assembly Patterning (SMAP) technique was used to grow fibroblasts in the presence of serum on 5*5 µm TiO@sub 2@ spots. Cytoskeletal organization in the fibroblasts was induced above the 5*5 µm TiO@sub 2@ patches, while no interaction with the PLL-g-PEG background was evident. The SMAP technique is considered to be highly suitable for reproducible and cost-effective fabrication of biologically-relevant patterns over large areas, by combining state-of-the-art photolithography and simple self-assembly dip-and-wash processes. Its applicability to sub-micrometer patterns is currently being evaluated.