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Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
Self-assembly of an optically active conjugated oligoelectrolyte
Julia H Ortony1, Tirtha Chatterjee, Logan E Garner
1Department of Chemistry and Biochemistry, Center for Polymers and Organic Solids, University of California, Santa Barbara, California 93106, USA.
Journal of the American Chemical Society
|May 10, 2011
Summary
Conjugated oligoelectrolytes like DSBNI form nanocylinders in water, enhancing optical properties such as two-photon absorption. This self-assembly is crucial for optoelectronic device applications.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Optoelectronics
Background:
- Conjugated oligoelectrolytes are vital for optoelectronics, biosensors, and transmembrane charge transport.
- Aqueous solubility is key for these applications, yet self-assembly effects on optical properties are understudied.
Purpose of the Study:
- Investigate how the self-assembly of DSBNI (1,4-bis(4'-(N,N-bis(6''-(N,N,N-trimethylammonium)hexyl)amino)-styryl)benzene tetraiodide) in water affects its optical properties.
- Determine the structural characteristics of DSBNI aggregates.
Main Methods:
- Liquid atomic force microscopy (AFM) and cryogenic transmission electron microscopy (cryo-TEM) for imaging.
- Small-angle neutron scattering (SANS) for in situ aggregate dimension quantification.
Main Results:
- DSBNI aggregation increases fluorescence lifetimes and two-photon absorption cross sections, with hypsochromic shifts.
- Planar DSBNI molecules stack into nanocylinders above a critical concentration.
- AFM and cryo-TEM suggest surface interactions can promote fiber formation, while SANS indicates consistent packing with lower aspect ratios.
Conclusions:
- DSBNI self-assembly into nanocylinders significantly alters optical properties.
- Understanding aggregate structure and optical evolution is key for designing new optoelectronic materials.
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