AVS 52nd International Symposium
    Biomaterial Interfaces Wednesday Sessions
       Session BI1-WeM

Paper BI1-WeM9
Immobilization of Protein Nano-Clusters on Polymeric Nano-Craters

Wednesday, November 2, 2005, 11:00 am, Room 311

Session: Protein-Surface Interactions
Presenter: P. Colpo, EC-JRC-IHCP Italy
Authors: A. Valsesia, EC-JRC-IHCP Italy
P. Colpo, EC-JRC-IHCP Italy
M. Lejeune, EC-JRC-IHCP Italy
F. Bretagnol, EC-JRC-IHCP Italy
T. Meziani, EC-JRC-IHCP Italy
F. Rossi, EC-JRC-IHCP Italy
Correspondent: Click to Email
The reduction of the typical length scale in the creation of patterned surfaces is of high interest in the field of bio-interacting materials and more particularly for biosensors design. For instance, the creation of sub-micrometric or nano-metric patterns is important for the miniaturization of the actual protein and DNA micro-spotting technology, or for the minimization of the non-specific absorption in biosensors, or to increase the orientation capability of immunosensors. To generate these patterned surfaces at the submicron level, the use of classical optical lithography methods becomes complex, since they are reaching the diffraction limits when the feature sizes are lower than 200 nm. Among the alternative techniques of lithography such as E-beam, nano-sphere lithography is a reliable method to produce nano-topography over large area surfaces. In this work we developed a reliable technique to produce polymeric nano-craters with bio-specific carboxylic functionalities and with controlled surface density and distribution, surrounded by an homogeneous matrix of anti fouling polymer. The process has been carried out combining plasma deposition and etching techniques with colloidal masking. The plasma etching process parameters have to be accurately studied in order to create the nano-structures without affecting their chemical properties. The micro-structural characterization of the nano-structured films was carried out by the combination of Ellipsometry, FT-IR spectroscopy and Atomic Force Microscopy (AFM). The surface chemical contrast at the nano-scale was characterized by using Chemical Force Microscopy. The creation of nano-patterned surfaces with controlled topography and chemistry at the sub-micron scale was demonstrated. In particular a contrast in the wettability between the two nano-regions was observed. The preferential absorption of the biomolecules inside the fouling nano-craters was demonstrated by Confocal Fluorescence Microscopy measurements.