Single step neutravidin patterning: a lithographic approach for patterning proteins

Protein patterning on surfaces is studied extensively for its potential use in proteomic, nanostructures, drug delivery and sensing. Patterning of proteins at micro and nano scales is especially important not only to understand the function of patterned protein but also to study its interaction with subsequent layers of bio-molecules/cells. Micro scale protein patterning is especially difficult due to the fragile nature of proteins. The already available methods either involve complex chemistries or are specific to a few proteins. Thus, in this regard, a versatile approach to pattern proteins using neutravidin is developed. With this approach of lithography and subsequent lift-off of the photoresist, any biotinylated moiety can be patterned at micron scale resolution. Functionality of patterned neutravidin is confirmed by showing binding of biotinylated polystyrene beads and biotinylated antibodies. In addition, stronger physisorption of neutravidin on bare glass surface, as a result of acetone lift-off, helps sustain the protein layers onto the glass surface without the need of chemical immobilization.