Abstract
The vision of nanoscale self-assembly research is the programmable synthesis of macroscale structures with controlled long and short-range order that exhibit a desired set of properties and functionality. However, strategies to reliably isolate and manipulate the nanoscale building blocks based on their size, shape, or chemistry are still in their infancy. Among the promising candidates, DNA-mediated self-assembly has enabled the programmable assembly of nanoparticles into complex architectures. In particular, two-dimensional assembly on substrates has potential for the development of integrated functional devices and analytical systems. Here, we combine the high-resolution patterning capabilities afforded by electron-beam lithography with the DNA-mediated assembly process to enable direct-write grayscale DNA density patterning. This method allows modulation of the functionally active DNA surface density to control the thermodynamics of interactions between nanoparticles and the substrate. We demonstrate that size-selective directed assembly of nanoparticle films from solutions containing a bimodal distribution of particles can be realized by exploiting the cooperativity of DNA binding in this system. To support this result, we study the temperature-dependence of nanoparticle assembly, analyze the DNA damage by X-ray photoelectron spectroscopy and fluorescence microscopy, and employ molecular dynamics simulations to explore the size-selection behavior.
Original language | English (US) |
---|---|
Pages (from-to) | 5679-5686 |
Number of pages | 8 |
Journal | ACS nano |
Volume | 10 |
Issue number | 6 |
DOIs | |
State | Published - Jun 28 2016 |
Funding
The SEM, EBL, and XPS work made use of the EPIC and Keck-II facilities in the NUANCE Center at Northwestern University which has received support from the MRSEC program (NSF DMR- 1121262) at the Materials Research Center; the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF NNCI-1542205); and the International Institute for Nanotechnology (IIN); the Keck Foundation and the State of Illinois, through the IIN.
Keywords
- DNA nanotechnology
- directed assembly
- electron-beam lithography
- nanoparticle assembly
- nanopatterning
- self-assembly
ASJC Scopus subject areas
- General Engineering
- General Materials Science
- General Physics and Astronomy