AVS 47th International Symposium
    Biomaterial Interfaces Wednesday Sessions
       Session BI-WeA

Paper BI-WeA7
Design and Characterization of Specific Biorecognition Interfaces using Derivatized Poly(L-lysine)-grafted-poly(ethylene glycol) Monolayers

Wednesday, October 4, 2000, 4:00 pm, Room 202

Session: Non-fouling Surfaces
Presenter: L.A. Ruiz-Taylor, Zyomyx, Inc.
Authors: L.A. Ruiz-Taylor, Zyomyx, Inc.
T.L. Martin, Zyomyx, Inc.
M. Heidecker, Zyomyx, Inc.
P. Indermuhle, Zyomyx, Inc.
P. Wagner, Zyomyx, Inc.
Correspondent: Click to Email
Control of interfacial events such as specific recognition versus non-specific protein adsorption is a major issue in biotechnological applications. In diagnostic assays or biomaterial devices, non-specific binding events can often be the limiting factor towards higher detection sensitivity or implant integration, respectively. In this study, we report the design of interfacial polymers that have the ability to spontaneously adsorb to negatively charged surfaces under physiological pH and efficiently repel non-specific protein adsorption while providing PEG tethered functional/active sites for specific biomolecule recognition. As a model system, we synthesized biotin-derivatized poly(L-lysine)-grafted-poly(ethylene glycol) copolymers, PLL-g-(PEG)(1-x)(PEG-biotin)x, where x varies from 0.1 to 1. XPS was used to characterize the properties and the organization of the monolayers formed on titanium dioxide. Molecular recognition properties were investigated using radiolabelled streptavidin alone and within complex protein mixtures. We showed that the system allows the specific recognition of streptavidin, that the extent of the recognition is not influenced by the presence of other proteins and that streptavidin-horseradish peroxidase displays enzymatic activity on the modified surfaces. Finally, we used the PLLPEG-biotin copolymer system in conjunction with microfluidic patterning techniques to provide micron-size features with specific protein recognition separated by areas preventing non-specific binding, as shown by AFM and fluorescence microscopy.