Topographically flat, chemically patterned PDMS stamps made by dip-pen nanolithography.
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ABSTRACT:
SUBMITTER: Zheng Z
PROVIDER: S-EPMC3065202 | biostudies-literature | 2008
REPOSITORIES: biostudies-literature
Publications
Topographically flat, chemically patterned PDMS stamps made by dip-pen nanolithography.
Zheng Zijian Z Jang Jae-Won JW Zheng Gengfeng G Mirkin Chad A CA
Angewandte Chemie (International ed. in English) 20080101 51
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Project description:The application of graphene in sensor devices depends on the ability to appropriately functionalize the pristine graphene. Here we show the direct writing of tailored phospholipid membranes on graphene using dip-pen nanolithography. Phospholipids exhibit higher mobility on graphene compared with the commonly used silicon dioxide substrate, leading to well-spread uniform membranes. Dip-pen nanolithography allows for multiplexed assembly of phospholipid membranes of different functionalities in close proximity to each other. The membranes are stable in aqueous environments and we observe electronic doping of graphene by charged phospholipids. On the basis of these results, we propose phospholipid membranes as a route for non-covalent immobilization of various functional groups on graphene for applications in biosensing and biocatalysis. As a proof of principle, we demonstrate the specific binding of streptavidin to biotin-functionalized membranes. The combination of atomic force microscopy and binding experiments yields a consistent model for the layer organization within phospholipid stacks on graphene.
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