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

Paper BI-TuM4
Neurite Outgrowth on Well Characterized Surfaces: Chemically and Spatially Controlled Fibronectin and RGD Substrates

Tuesday, November 4, 2003, 9:20 am, Room 307

Session: Cell/Surface Interactions
Presenter: Z Zhang, University of Delaware
Authors: Z Zhang, University of Delaware
R. Yoo, University of Delaware
M. Wells, University of Delaware
T.P. Beebe, Jr., University of Delaware
R. Biran, University of Utah
P. Tresco, University of Utah
J. Hyun, Duke University
W. Jun, Duke University
A. Chilkoti, Duke University
Correspondent: Click to Email
Study of axonal growth and ligand-receptor interactions requires specificity and careful characterization of the biomaterial substrates to which the neurons bind. Without highly specific surface characterization, it would be impossible to predict the effects of ligand surface density, spatial distribution, and conformation on the outgrowth of a neuron. Here we report two different methods of surface modification (a heterobifunctional crosslinker and Pluronics @super TM@) for immobilization of fibronectin (FN) and fibronectin-derived RGD-containing peptides to the substrates. Proteins and peptides were immobilized to glass surfaces at different concentrations. Various surface analytical techniques, such as contact angle, x-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (TOF-SIMS) were used for analysis of the substrates at each step of the two different chemistries involved. After immobilization of fibronectin and RGD-containing oligopeptides, the modified surfaces were plated with dorsal root ganglia neurons of the rat. Neuron outgrowth rates on the various surfaces were measured and different bioactivity was observed on different modified surfaces. In order to spatially control neurite outgrowth on the substrates, patterned and gradiently FN-covered surfaces were synthesized and tested for bioactivity. An amphiphilic comb polymer presenting oligoethylene glycol side-chains was used to create microcontact-printed patterned surfaces because of its excellent protein repellant and cell resistance properties.