la0534773_si_001.pdf (370.73 kB)
Deposition of DNA-Functionalized Gold Nanospheres into Nanoporous Surfaces
journal contribution
posted on 2006-05-23, 00:00 authored by Krisanu Bandyopadhyay, Eric Tan, Lin Ho, Sarah Bundick, Shenda M. Baker, Angelika NiemzWe report the deposition of DNA-conjugated gold nanospheres into arrays of surface nanopores obtained from
hexagonally ordered thin polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA) diblock copolymer films on silicon.
The deposition occurs spontaneously from aqueous solution and is driven by either electrostatic interactions or specific
DNA hybridization events between the DNA nanospheres and the surface nanopores. To mitigate this spontaneous
deposition, we have chemically modified the nanopores with either positively charged aminosilanes or oligonucleotide
probe sequences. The deposition of DNA nanospheres into the surface nanopores was characterized by atomic force
microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). We have observed preferential immobilization of
individual DNA nanospheres within the nanopores, based on the size matching between the two entities. The inclusion
density and selectivity of DNA nanosphere deposition into the surface nanopores was found to depend predominantly
on the methods through which the nanoporous surfaces were prepared and chemically functionalized.