AVS 53rd International Symposium
    Biomaterial Interfaces Friday Sessions
       Session BI-FrM

Paper BI-FrM8
Electrodeposition of Chitosan for BioMEMS: Real-Time, In-Vitro, and Post-Process Characterization

Friday, November 17, 2006, 10:20 am, Room 2014

Session: Biomolecular Surface Characterization II
Presenter: S.L. Beatty, University of Maryland
Authors: S.L. Beatty, University of Maryland
E.C. Dreyer, University of Maryland
X. Luo, University of Maryland
G. Rubloff, University of Maryland
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Chitosan has been shown to serve as a robust and reproducible scaffold for biological functionalization in microfluidic channels, using chitosan electrodeposition at specific bioMEMS sites. To better understand the materials and process science of chitosan electrodeposition onto metal electrodes, we have used both in vitro characterization techniques and post-deposition measurements of air-dried films. Real-time current, voltage, and optical reflectivity show film growth nonlinearities expected for electrical vs. optical property sensing. Raman spectroscopy of films air-dried after electrodeposition reveals the presence of primary amine groups active in biofunctionalization. AFM images of the air-dried films reveal variable and rough morphology not directly correlated to deposition conditions, while hydration increased surface homogeneity. Fluorescence microscopy using fluorescently decorated chitosan shows both film growth and its spatial distribution across the deposition electrode, enabling a comparison of in-vitro and dry morphology of the chitosan film. While the in-vitro images show fairly smooth distribution of chitosan, the air-dried films are much rougher, indicating nonuniform and unpredictable collapse of the film's structure during drying. Thus, in vitro measurements of the film deposition and structure are essential to exploit the potential of chitosan as a platform for biotechnology applications.