Protein patterning on self-assembled polyelectrolyte thin films

This study demonstrated a simple micropatterning method using engineered surface and microcontact printing (mu CP). For the selection of appropriate surface, several representative surfaces modified with various functional materials including aldehyde, epoxide, poly-L-lysine, amine, and self-assembled polyelectrolyte multilayers (PEL) were investigated. The PEL coated surface endowing electrostatic interaction force showed most high functionality in point of homogeneous patterning of proteins with high density and preservation of inherent three-dimensional structure of proteins. The printed sizes of protein micropatterns were almost identical to the used microstamp, which proves the mu CP method is independent of diffusion of the transferring proteins. At last, the immunoassay as a model system of protein-protein interaction showed good linearity over a range from 100 to 25 mu g/ml, indicating the feasibility of a quantitative measurement of the concentration of target proteins in sample. Our proposed approach will be useful for the development of biomedical microdevices because of green chemistry, simple process, and high potential of various applications. (c) 2007 Elsevier Ltd. All rights reserved.