| Abstract
| - This paper investigates three different approaches to patterning proteins within ultrathin resist layersformed from self-assembled monolayers using scanning probe lithography (SPL) at the submicrometerlength scale. The first approach uses a “nanografting” method to pattern a reactive carboxylic acid terminatedthiol into a resist composed of a methyl-terminated monolayer. Rabbit IgG antigen is bound to the patternedregion, and an immunoassay utilizing direct readout of the topographic change resulting from specificbinding of anti-rabbit IgG antibody is performed using scanning force microscopy. To address issues relatedto nonspecific protein adsorption, the other two approaches investigated the patterned removal of glycol-terminated monolayers by mechanically “scraping” patterns at high tip−sample forces by SPL. Proteinattachment to the scraped regions was achieved either through the chemisorption of a disulfide couplingagent or by the direct adsorption of Fab‘-SH antibody fragments. Results obtained from all approachesare presented and compared, and the strengths and weaknesses of each toward fabricating high-density,multiple protein arrays are discussed.
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