AVS 53rd International Symposium
    Biomaterial Interfaces Tuesday Sessions
       Session BI-TuP

Paper BI-TuP3
QCM-D and AFM Characterization of the Adsorption and Functionality of Laminin in Large Area Nanopatterns for the Study of Neural Stem Cells

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Biomaterial Interfaces Poster Session
Presenter: J. Malmstrom, University of Aarhus, Denmark
Authors: J. Malmstrom, University of Aarhus, Denmark
H. Agheli, Chalmers University of Technology, Sweden
E.M. Larsson, Chalmers University of Technology, Sweden
M. Textor, ETH Zurich, Switzerland
D.S. Sutherland, University of Aarhus, Denmark
Correspondent: Click to Email
A number of reports have made use of chemical or topographic surface structures to pattern assemblies of neural cells in an effort to control their growth and development. Here a nanostructured surface is used to immobilize Laminin at discrete locations on a solid substrate in well-defined nanometer scale patterns in order to investigate the response of neural stem cells (AHP - adult hippocampal progenitor). Nanostructured quartz crystal oscillators and silicon wafer chips with ~120nm diameter regions of alkanethiol modified gold on a silicon oxide background are produced by colloidal lithography. Immobilization of protein resistant layers (PLL-g-PEG) specifically to the silicon oxide parts of the surface allows the generation of nanoscale patches of protein by the non-specific adsorption to the hydrophobically modified gold. The adsorption of Laminin onto homogenous and nanostructured surfaces is studied with parallel sets of samples using the Quartz Crystal Microbalance with dissipation (QCM-D) and Atomic Force Microscopy (AFM). Viscoelastic modeling of the QCM-D data, supported by surface plasmon resonance (SPR) data, on homogenous surfaces indicate a thick hydrated Laminin layer (71±2 nm, >95% water) with high antibody binding capacity (~3 polyclonal anti-Laminin IgG's binding per surface bound Laminin). QCM-D data indicates a higher surface density of Laminin binding for the structured surfaces than the homogeneous surfaces and a greater IgG binding capacity. A new approach to analyze AFM height histograms is used to quantify protein and monoclonal/polyclonal anti-Laminin antibody binding to the nanoscale patches showing <40 proteins per patch.