Nanostructured submicron block copolymer dots by sacrificial stamping: a potential preconcentration platform for locally resolved sensing, chemistry and cellular interactions

Classical contact lithography involves patterning of surfaces by embossing or by transfer of ink. We report direct lithographic transfer of parts of sacrificial stamps onto counterpart surfaces. Using sacrificial stamps consisting of the block copolymer polystyrene-block-poly(2-pyridine) (PS-b-P2VP), we deposited arrays of nanostructured submicron PS-b-P2VP dots with heights of about 100 nm onto silicon wafers and glass slides. The sacrificial PS-b-P2VP stamps were topographically patterned with truncated-pyramidal contact elements and penetrated by spongy-continuous nanopore systems. The spongy nature of the sacrificial PS-b-P2VP stamps supported formation of adhesive contact to the counterpart surfaces and the rupture of the contact elements during stamp retraction. The submicron PS-b-P2VP dots generated by sacrificial stamping can be further functionalized, examples include loading submicron PS-b-P2VP dots with dyes and attachment of gold nanoparticles to their outer surfaces. The arrays of submicron PS-b-P2VP dots can be integrated into setups for advanced optical microscopy, total internal reflection fluorescence microscopy or Raman microscopy. Arrays of nanostructured submicron block copolymer dots may represent a preconcentration platform for locally resolved sensing and locally resolved monitoring of cellular interactions or might be used as microreactor arrays in lab-on-chip configurations.