Single-strand DNA-nanorod conjugates - tunable anisotropic colloids for on-demand self-assembly

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:586

Article

Sutter, Eli¹  Zhang, Bo¹  Sutter, Peter² 

[1] Univ Nebraska Lincoln, Dept Mech & Mat Engn, Lincoln, NE 68588 USA

[2] Univ Nebraska Lincoln, Dept Elect & Comp Engn, Nebraska Hall E421B, Lincoln, NE 68588 USA

关键词: Self-assembly;    Nanocolloids;    Nucleic acid;    DNA;    Protonation;    In-situ microscopy;    Gold nanorods;    Electrostatic repulsion;    Van der Waals attraction;   

DOI  :  10.1016/j.jcis.2020.11.009

来源: Elsevier

【 摘 要 】

Directed self-assembly uses different stimuli to initiate and control the interaction between nanocrystals. Protonation at reduced pH represents a convenient stimulus for initiating self-assembly. Prior work has focused on protonation-induced hydrogen bonding between peptide or amino acid functionalized nanocrystals for reversible cycling between dispersed and aggregated states. Here, we discuss a fundamentally different approach, in which changes in pH modify the nonspecific interparticle interaction between Au nanorods conjugated with single-stranded (ss) DNA. While electrostatic repulsion stabilizes dispersed suspensions at neutral pH, protonation in acidic solution modifies the DNA corona, turning the interaction between the rods attractive and triggering their self-assembly. Analysis of in-situ electron microscopy of ssDNA-Au nanorods in solution is consistent with a van der Waals attraction of charge-neutral monomers at acidic pH. The results demonstrate ssDNA-conjugated anisotropic nanostructures as versatile building blocks with stimuli-programmable interactions for on-demand self-assembly. (C) 2020 Elsevier Inc. All rights reserved.

【 授权许可】

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