Multiplexed lipid dip-pen nanolithography on subcellular scales for the templating of functional proteins and cell culture.

Molecular patterning processes taking place in biological systems are challenging to study in vivo because of their dynamic behavior, subcellular size, and high degree of complexity. In vitro patterning of biomolecules using nanolithography allows simplification of the processes and detailed study of the dynamic interactions. Parallel dip-pen nanolithography (DPN) is uniquely capable of integrating functional biomolecules on subcellular length scales due to its constructive nature, high resolution, and high throughput. Phospholipids are particularly well suited as inks for DPN since a variety of different functional lipids can be readily patterned in parallel. Here DPN is used to spatially pattern multicomponent micro- and nanostructured supported lipid membranes and multilayers that are fluid and contain various amounts of biotin and/or nitrilotriacetic acid functional groups. The patterns are characterized by fluorescence microscopy and photoemission electron microscopy. Selective adsorption of functionalized or recombinant proteins based on streptavidin or histidine-tag coupling enables the semisynthetic fabrication of model peripheral membrane bound proteins. The biomimetic membrane patterns formed in this way are then used as substrates for cell culture, as demonstrated by the selective adhesion and activation of T-cells.