scholarly journals Reversible end-to-end assembly of selectively functionalized gold nanorods by light-responsive arylazopyrazole–cyclodextrin interaction

2019 ◽  
Vol 15 ◽  
pp. 1407-1415 ◽  
Author(s):  
Maximilian Niehues ◽  
Patricia Tegeder ◽  
Bart Jan Ravoo
Keyword(s):  
Gold Nanorods ◽  
Self Assembly ◽  
Ligand Exchange ◽  
Cetyltrimethylammonium Bromide ◽  
Complete Removal ◽  
Tetraethylene Glycol ◽  
Functionalized Nanoparticles ◽  
Organic Hybrid ◽  
Cross Linker ◽  
End To End

We propose a two-step ligand exchange for the selective end-functionalization of gold nanorods (AuNR) by thiolated cyclodextrin (CD) host molecules. As a result of the complete removal of the precursor capping agent cetyltrimethylammonium bromide (CTAB) by a tetraethylene glycol derivative, competitive binding to the host cavity was prevented, and reversible, light-responsive assembly and disassembly of the AuNR could be induced by host–guest interaction of CD on the nanorods and a photoswitchable arylazopyrazole cross-linker in aqueous solution. The end-to-end assembly of AuNR could be effectively controlled by irradiation with UV and visible light, respectively, over four cycles. By the introduction of AAP, previous disassembly limitations based on the photostationary states of azobenzenes could be solved. The combination photoresponsive interaction and selectively end-functionalized nanoparticles shows significant potential in the reversible self-assembly of inorganic–organic hybrid nanomaterials.

scholarly journals Effective replacement of cetyltrimethylammonium bromide (CTAB) by mercaptoalkanoic acids on gold nanorod (AuNR) surfaces in aqueous solutions

Nanoscale ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 658-668 ◽  
Author(s):  
Rafael del Caño ◽  
Jose M. Gisbert-González ◽  
Jose González-Rodríguez ◽  
Guadalupe Sánchez-Obrero ◽  
Rafael Madueño ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Gold Nanorods ◽  
Ligand Exchange ◽  
Cetyltrimethylammonium Bromide ◽  
Gold Nanorod ◽  
Experimental Conditions ◽  
Seed Mediated ◽  
The Stability

The highly packed cetyltrimethylammonium bromide bilayer on the surface of gold nanorods synthesized by the seed-mediated procedure hampers the complete ligand exchange under experimental conditions that preserves the stability of the dispersions.

Chiral Plasmonic Nanochains via the Self-Assembly of Gold Nanorods and Helical Glutathione Oligomers Facilitated by Cetyltrimethylammonium Bromide Micelles

ACS Nano ◽  
2017 ◽  
Vol 11 (4) ◽  
pp. 3463-3475 ◽  
Author(s):  
Jun Lu ◽  
Yi-Xin Chang ◽  
Ning-Ning Zhang ◽  
Ying Wei ◽  
Ai-Ju Li ◽  
...  
Keyword(s):  
Gold Nanorods ◽  
Self Assembly ◽  
Cetyltrimethylammonium Bromide ◽  
The Self

End-to-end self-assembly and colorimetric characterization of gold nanorods and nanospheres via oligonucleotide hybridization

2005 ◽  
Vol 16 (9) ◽  
pp. 1776-1780 ◽  
Author(s):  
Bifeng Pan ◽  
Limei Ao ◽  
Feng Gao ◽  
Hongye Tian ◽  
Rong He ◽  
...  
Keyword(s):  
Gold Nanorods ◽  
Self Assembly ◽  
Oligonucleotide Hybridization ◽  
Colorimetric Characterization ◽  
End To End

Removal of Cetyltrimethylammonium Bromide to Enhance the Biocompatibility of Au Nanorods Synthesized by a Modified Seed Mediated Growth Process

2008 ◽  
Vol 8 (9) ◽  
pp. 4670-4674 ◽  
Author(s):  
Byung-Sang Choi ◽  
Muhammad Iqbal ◽  
Takhee Lee ◽  
Young Ha Kim ◽  
Giyoong Tae
Keyword(s):  
Gold Nanorods ◽  
Cetyltrimethylammonium Bromide ◽  
Growth Process ◽  
Complete Removal ◽  
Au Nanorods ◽  
Nir Absorption ◽  
Seed Mediated ◽  
The Stability ◽  
Growth Approach

Previously, we reported the synthesis of stable gold nanorods with higher aspect ratio (∼15–20) and more enhanced uniformity by a modified seed mediated growth approach using a binary surfactant system consisting of CTAB and Pluronic F-127. For the in vivo application of gold nanorods, the removal of CTABs that are strongly bound on prepared Au nanorods is necessary due to their cytotoxicity. Use of heat or acid at various conditions was performed to achieve the complete removal of CTAB from the synthesized Au nanorods while maintaining their stability. Here, we report the appropriate conditions for both treatments that can remove CTAB efficiently without hampering the stability of Au nanorods. After the removal of CTAB, Pluronic F-127 was added additionally for the stabilization and further potential functionalization of Au nanorods to make useful for various applications. VIS-NIR absorption spectroscopy, SEM, TEM, and FTIR were used for characterization.

Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

2018 ◽  
Author(s):  
Elaine A. Kelly ◽  
Judith E. Houston ◽  
Rachel Evans
Keyword(s):  
Real Time ◽  
Absorption Spectroscopy ◽  
Self Assembly ◽  
Uv Light ◽  
Wormlike Micelles ◽  
Tetraethylene Glycol ◽  
Light Illumination ◽  
First Time ◽  
Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such as<i></i>drug delivery and micellar catalysis. Currently, their behaviour in the equilibrium <i>cis-</i>and <i>trans</i>-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>) using small-angle neutron scattering (SANS). We show that the incorporation of <i>in-situ</i>UV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>could switch between wormlike micelles (<i>trans</i>native state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked <i>in</i><i>-situ</i>through combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

Plasmon-Enhanced Chemical Reaction at the Hot Spots of End-to-End Assembled Gold Nanorods

2020 ◽  
Vol 124 (5) ◽  
Author(s):  
Srimanta Pal ◽  
Anushree Dutta ◽  
Manideepa Paul ◽  
Arun Chattopadhyay
Keyword(s):  
Chemical Reaction ◽  
Gold Nanorods ◽  
Hot Spots ◽  
End To End

Plasmonics tunable Ag-coated gold nanorods arrays as reusable SERS substrates for multiplexed antibiotics detection

2021 ◽  
Author(s):  
Xiaoya Peng ◽  
Dan Li ◽  
Yuanting Li ◽  
Haibo Xing ◽  
Wei Deng
Keyword(s):  
Gold Nanorods ◽  
Self Assembly ◽  
Aqueous Media ◽  
Antibiotic Residues ◽  
Sers Substrates ◽  
Antibiotics Detection ◽  
Robust Strategies

Antibiotic contaminants in aqueous media pose serious threat to human and ecological environments. Therefore, it is necessary to develop robust strategies to detect antibiotic residues. For this purpose, a self-assembly...

Sign in / Sign up

Export Citation Format

Share Document