AVS 52nd International Symposium
    Biomaterial Interfaces Monday Sessions
       Session BI-MoP

Paper BI-MoP36
Formation of Carbohydrate Microarrays with the MAPL Technique for the Detection of Specific Interactions

Monday, October 31, 2005, 5:00 pm, Room Exhibit Hall C&D

Session: Biomaterial Interfaces Poster Session
Presenter: K. Barth, ETH Zurich, Switzerland
Authors: K. Barth, ETH Zurich, Switzerland
G. Coullerez, ETH Zurich, Switzerland
M. Textor, ETH Zurich, Switzerland
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Carbohydrates play an important role in many biological processes, like cell-cell and cell-pathogen recognition.@footnote 1@ Because of missing analytic tools there is until now little known about the role of carbohydrates in these processes. Therefore it exists a need for methods that allow high throughput screening of these specific interactions.@footnote 2@ We have newly developed a method to covalently graft mono-, di- and trimannosides to the polycationic copolymer poly(L-lysine)-graft-poly(ethylene glycol) (PLL-[g]-PEG). With this system it is possible to tailor the density and distribution of the immobilized mannosides on the polymer backbone. While spontaneously adsorbed on negatively charged oxides surfaces (Nb @sub 2@O@sub 5@, TiO@sub 2@) the copolymers show specific lectin and bacteria recognition. Furthermore we could demonstrate the dependence of the carbohydrate surface density for the interactions between the mannoside and the multivalent model systems Concanavalin A (Con A) or Escherichia coli (E. coli). This was done with methods like Optical Waveguide Lightmode Spectroscopy where no additional labeling is required. In order to develop arrays, we propose herein to combine this chemical approach with the patterning method MAPL (Molecular assembly pattering by lift-off) developed by Falconnet et al.@footnote 3@ This technique combines photolithography and the attribute of functionalized PLL-[g]-PEG to form uniform layers on many metal oxide surfaces. We are able to control the pattern geometry and size as well as the surface density of the mannosides in the adhesive patterns. Fluorescent labeled Con A and E. coli can be easily detected and is proofing the high specificity of the developed system with a non fouling background. @FootnoteText@ @footnote 1@ Sharon et al., Sci. Am. 1993, 268, 82.@footnote 2@ Seeberger et al., ChemBioChem 2004, 5, 1375.@footnote 3@ Falconnet et al., Nano Letters, 2004, 4, 1909.