scholarly journals In Situ Self-Assembly of Ultrastable Gold Nanoparticles on Polyvinyl Alcohol Nanofibrous Mats for Use as Highly Reusable Catalysts

ACS Omega ◽  
2019 ◽  
Vol 4 (22) ◽  
pp. 20094-20100
Author(s):  
Lin Xu ◽  
Hongping Xiang ◽  
Zhengjian Chen ◽  
Xu Zhang
Keyword(s):  
Gold Nanoparticles ◽  
Polyvinyl Alcohol ◽  
Self Assembly

Monitoring pattern formation in drying and wetting dispersions of gold nanoparticles by ESEM

2015 ◽  
Vol 181 ◽  
pp. 281-298 ◽  
Author(s):  
Casper Kunstmann-Olsen ◽  
Domagoj Belić ◽  
Mathias Brust
Keyword(s):  
Gold Nanoparticles ◽  
Self Assembly ◽  
Early Stage ◽  
Environmental Scanning Electron Microscopy ◽  
Water Soluble ◽  
Environmental Scanning ◽  
Evaporation And Condensation ◽  
Lift Off ◽  
Poly Ethylene

We report an investigation of the self-assembly of patterns from functionalized gold nanoparticles (GNPs) by monitoring the process in situ by environmental scanning electron microscopy (ESEM) during both evaporation and condensation of the dispersant. As this method limits the choice of dispersants to water, GNPs functionalized with hydrophilic thiol ligands, containing poly(ethylene)glycol (PEG) groups, were used on a variety of substrates including pre-patterned ones. Particular emphasis was given to early stage deposition of GNPs, as well as redispersion and lift-off upon condensation of water droplets. ESEM presents a unique opportunity of directly imaging such events in situ. It was found that attractive interactions between the substrate and the GNPs are often stronger than expected once the particles have been deposited. The role of nickel perchlorate as a highly water-soluble additive was studied. It was found that entropically driven deposition of particles and decoration of surface features was enhanced in its presence, as expected.

scholarly journals In situ self-assembly of gold nanoparticles on hydrophilic and hydrophobic substrates for influenza virus-sensing platform

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Syed Rahin Ahmed ◽  
Jeonghyo Kim ◽  
Van Tan Tran ◽  
Tetsuro Suzuki ◽  
Suresh Neethirajan ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Influenza Virus ◽  
Self Assembly ◽  
Sensing Platform

In Situ Visualization of Self-Assembly of Charged Gold Nanoparticles

2013 ◽  
Vol 135 (10) ◽  
pp. 3764-3767 ◽  
Author(s):  
Yuzi Liu ◽  
Xiao-Min Lin ◽  
Yugang Sun ◽  
Tijana Rajh
Keyword(s):  
Gold Nanoparticles ◽  
Self Assembly ◽  
In Situ Visualization

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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.

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