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arXiv · 1902.08883

Linker-mediated phase behavior of DNA-coated colloids

Janna Lowensohn·Bernardo Oyarzún·Guillermo Narvaez Paliza·Bortolo M. Mognetti·W. Benjamin Rogers
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Abstract

The possibility of prescribing local interactions between nano- and microscopic components that direct them to assemble in a predictable fashion is a central goal of nanotechnology research. In this article we advance a new paradigm in which self-assembly of DNA-functionalized colloidal particles is programmed using linker oligonucleotides dispersed in solution. We find a phase diagram that is surprisingly rich compared to phase diagrams typical of other DNA-functionalized colloidal particles that interact by direct hybridization, including a re-entrant melting transition upon increasing linker concentration, and show that multiple linker species can be combined together to prescribe many interactions simultaneously. A new theory predicts the observed phase behavior quantitatively without any fitting parameters. Taken together, these experiments and model lay the groundwork for future research in programmable self-assembly, enabling the possibility of programming the hundreds of specific interactions needed to assemble fully-addressable, mesoscopic structures, while also expanding our fundamental understanding of the unique phase behavior possible in colloidal suspensions.

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Janna Lowensohn, Bernardo Oyarzún, Guillermo Narvaez Paliza, Bortolo M. Mognetti, W. Benjamin Rogers. 2019-02-24. Linker-mediated phase behavior of DNA-coated colloids. https://doi.org/10.1103/physrevx.9.041054

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