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Self-assembly of amphiphilic small molecules in water leads to nanostructures with customizable structure–property relationships arising from their tunable chemistries. Characterization of these assemblies is generally limited to their static structures – e.g. their geometries and dimensions – but the implementation of tools that provide a deeper understanding of molecular motions has recently emerged. Here, we summarize recent reports showcasing dynamics characterization tools and their application to small molecule assemblies, and we go on to highlight supramolecular systems whose properties are substantially affected by their conformational, exchange, and water dynamics. This review illustrates the importance of considering dynamics in rational amphiphile design.
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Two‐Dimensional Supramolecular Polymerization of DNA Amphiphiles is Driven by Sequence‐Dependent DNA‐Chromophore Interactions
Abstract Two‐dimensional (2D) assemblies of water‐soluble block copolymers have been limited by a dearth of systematic studies that relate polymer structure to pathway mechanism and supramolecular morphology. Here, we employ sequence‐defined triblock DNA amphiphiles for the supramolecular polymerization of free‐standing DNA nanosheets in water. Our systematic modulation of amphiphile sequence shows the alkyl chain core forming a cell membrane‐like structure and the distal π‐stacking chromophore block folding back to interact with the hydrophilic DNA block on the nanosheet surface. This interaction is crucial to sheet formation, marked by a chiral “signature”, and sensitive to DNA sequence, where nanosheets form with a mixed sequence, but not with a homogeneous poly(thymine) sequence. This work opens the possibility of forming well‐ordered, bilayer‐like assemblies using a single DNA amphiphile for applications in cell sensing, nucleic acid therapeutic delivery and enzyme arrays.
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- Award ID(s):
- 1945394
- PAR ID:
- 10418463
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 135
- Issue:
- 24
- ISSN:
- 0044-8249
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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