Dumbbell-shaped dendrimers — Synthesis and self-assembly

2008 ◽  
Vol 86 (6) ◽  
pp. 540-547 ◽  
Author(s):  
Tatiana Vassilieff ◽  
Ashok Kakkar
Keyword(s):  
Self Assembly ◽  
The Self ◽  
Layer By Layer ◽  
Acid Base ◽  
Detailed Characterization ◽  
Generation Number ◽  
Backbone Structure

We report on the synthesis and detailed characterization of dendrimers that evolve symmetrically from a linear core of 2-butyne-1,4-diol with 3,5-dihydroxybenzyl alcohol based dendron arms. The divergent layer-by-layer build-up of the dumbbell-shaped dendrimers is based on simple acid–base hydrolytic chemistry of bis(dimethylamino)dimethylsilane with OH-terminated molecules. The self-assembly of these dendrimers in THF and water is significantly influenced by their generation number, the backbone structure, and the solvent.Key words: dendrimers, divergent synthesis, macromolecules, self-assembly

Characterization Of SnO2 Nanoparticles Deposited Via Layer-by-Layer Self Assembly And Investigation Of Their Sensing Properties

2002 ◽  
Vol 739 ◽  
Author(s):  
R. C. Ghan ◽  
Y. Lvov ◽  
R. S. Besser
Keyword(s):  
Self Assembly ◽  
High Selectivity ◽  
Sno2 Nanoparticles ◽  
Test Chamber ◽  
The Self ◽  
Layer By Layer ◽  
Product Analysis ◽  
Glass Substrates ◽  
Self Assembled

ABSTRACTA technique of Layer-by-Layer (LbL) self-assembly is used to deposit SnO2 nanoparticles on Quartz Crystal Microbalance (QCM) resonators, and on glass substrates which the authors believe has not been previously reported. Characterization of self-assembled SnO2 layers has been performed using QCM, Scanning Electron Microscopy (SEM), and Zeta Potential analysis.We have successfully deposited SnO2 nanoparticles on QCM resonator using self-assembly technique. LbL self-assembly is a method of organization of ultra-thin films by interlayer electrostatic attraction. The thickness and mass of the self-assembled layers can be characterized by the frequency shift obtained using the QCM and empirical equations relating change in frequency with mass and thickness of deposited layers. The deposition of SnO2 nanolayers exhibited a linear reproducibility and the process of self-assembly was independent of the residence time of QCM resonator in the SnO2 nanoparticle colloidal solution. High resolution SEM analysis reveals that the SnO2 nanoparticle layers are uniformly deposited across the entire substrate. Electrical characterization was performed on SnO2 nanoparticle layers self-assembled on glass substrates which were patterned for two point (current-voltage) IV characteristic measurements. Two classes of samples were used. One sample was self-assembled glass substrate patterned with electrical contacts and calcined (baked at 350°C for one hour) to eliminate interlayered polyions and the other sample was not calcined. Results revealed that the calcined samples demonstrated linear ohmic behavior but the uncalcined showed some spurious points which we believe are due to the polyion layers.Characterization of the self-assembled SnO2 nanoparticles is being carried out with the intention of fabricating a high-selectivity μ-gas sensor. A test chamber has been fabricated and results of resistance behavior of the sensor with variation in temperature have been presented.The sensor can find applications in high selectivity sensing of chemical, industrial, domestic, and hazardous environments. After further research and development, this μ-gas sensors could be made generic to sense a variety of gases and employed for integrated on-chip product analysis in multiple chemical microsystem applications.

Fabrication and Characterization of the Multilayer Film Containing Polyoxometalate with Pendant Support-Ligand

2007 ◽  
Vol 336-338 ◽  
pp. 2235-2237
Author(s):  
Hui Yuan Ma ◽  
Jun Peng ◽  
Fu Ping Wang ◽  
Bao Xia Dong
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Property ◽  
Self Assembly ◽  
Multilayer Film ◽  
Interface Roughness ◽  
The Self ◽  
Layer By Layer ◽  
The Mean ◽  
Fabrication And Characterization

A novel nanosized multilayer film containing polyoxometalate anion with a pendant supportligand α-[SiW11O39Co(H3P2O7)]7- (abbr. SiW11Co-P2O7) and poly(diallyldimethyl ammonium chloride (PDDA) was fabricated by layer-by-layer self-assembly. The multilayer film was characterized by XPS, UV-vis, AFM and ESR. The mean interface roughness was about 2.0 nm, calculated from an area of 0.5 × 0.5 μm2. The electrochemical property was studied by the cyclic voltammetry, the results indicating that the self-assembly film exhibited favorable electrochemical behavior of polyoxometalate.

Estimating the shape and size of supramolecular assemblies by variable temperature diffusion ordered spectroscopy

2014 ◽  
Vol 12 (40) ◽  
pp. 7932-7936 ◽  
Author(s):  
Benjamin M. Schulze ◽  
Davita L. Watkins ◽  
Jing Zhang ◽  
Ion Ghiviriga ◽  
Ronald K. Castellano
Keyword(s):  
Self Assembly ◽  
Variable Temperature ◽  
Supramolecular Assemblies ◽  
The Self ◽  
Conjugated Oligomers ◽  
Photovoltaic Devices ◽  
Temperature Diffusion ◽  
Shape And Size

Reported is characterization of the self-assembly of π-conjugated oligomers, molecules studied recently in photovoltaic devices, using variable temperature diffusion ordered spectroscopy; the approach has allowed estimation of assembly size, shape, and molecularity.

The Self-assembly, Characterization of Hepatocytes on Nano-sized Gold Colloid and Construction of Cellular Biosensor

2003 ◽  
Vol 32 (10) ◽  
pp. 934-935 ◽  
Author(s):  
Hai-Ying Gu ◽  
Rong-Xiao Sa ◽  
Su-Su Yuan ◽  
Hong-Yuan Chen ◽  
Ai-Min Yu
Keyword(s):  
Self Assembly ◽  
The Self ◽  
Gold Colloid

Size-tunable fluorescent dendrimersomes via aggregation-induced emission

2022 ◽  
Author(s):  
Marilyne Bélanger-Bouliga ◽  
Brandon Andrade-Gagnon ◽  
Diep Thi Hong Nguyen ◽  
Nazemi Ali
Keyword(s):  
Self Assembly ◽  
The Self ◽  
Third Generation ◽  
Thermodynamic Control ◽  
Aggregation Induced Emission ◽  
Generation Number ◽  
Dendrimer Generation

Tetraphenylethylene-functionalized amphiphilic Janus dendrimers of up to third generation are synthesized. Their self-assembly has been studied under kinetic and thermodynamic control. By varying the dendrimer generation number and the self-assembly...

The self-assembly and photophysical characterization of tri(cyclopenta[def]phenanthrene)-derived nanoparticles: a template free synthesis of hollow colloidosomes.

2010 ◽  
Vol 20 (43) ◽  
pp. 9684 ◽  
Author(s):  
Shanmugam Easwaramoorthi ◽  
Pyosang Kim ◽  
Jong Min Lim ◽  
Suhee Song ◽  
Honsuk Suh ◽  
...  
Keyword(s):  
Self Assembly ◽  
The Self ◽  
Template Free

Self-Assembly of Alkali Lignin in Tetrahydrofuran

2012 ◽  
Vol 550-553 ◽  
pp. 57-61
Author(s):  
Hao Li ◽  
Yong Hong Deng ◽  
Kai Huang
Keyword(s):  
Charge Transfer ◽  
Electrostatic Interaction ◽  
Self Assembly ◽  
The Self ◽  
Charge Transfer Complexes ◽  
Layer By Layer ◽  
Alkali Lignin ◽  
Higher Temperature ◽  
Effects Of Temperature

Alkali lignin (AL) was used as a polyanion to form layer-by-layer self-assembled film with PDAC as a polycation. The effects of temperature and concentration on the adsorption characteristics of AL were investigated. Iodine was added into AL solutions to study the role of π-π interaction in self-assembly of AL and PDAC. Results show that the self-assembly of AL/PDAC is mainly driven by π-π interaction and electrostatic interaction. A higher temperature or a larger concentration can enhance the aggregation of lignin. I2 can form lignin–iodine charge–transfer complexes with AL to reduce the degree of aggregation of AL, so the adsorbed amount of AL decreases significantly with increasing iodine contents.

scholarly journals Self-assembly of nucleopeptides to interact with DNAs

2017 ◽  
Vol 7 (6) ◽  
pp. 20160116 ◽  
Author(s):  
Xuewen Du ◽  
Jie Zhou ◽  
Xinming Li ◽  
Bing Xu
Keyword(s):  
Hydrogen Bonds ◽  
Plasmid Dna ◽  
Self Assembly ◽  
Unique Property ◽  
The Self ◽  
Proteinase K ◽  
Rational Approach ◽  
Proteolytic Resistance ◽  
Soft Biomaterials

As a novel class of biomaterials, nucleopeptides, via the conjugation of nucleobases and peptides, usually self-assemble to form nanofibres driven mainly by hydrogen bonds. Containing nucleobase(s), nucleopeptides have a unique property—interacting with nucleic acids. Here we report the design and characterization of nucleopeptides that self-assemble in water and are able to interact with single-stranded DNAs (ssDNAs). Containing nucleobases on their side chains, these nucleopeptides bind with the ssDNAs, and the ssDNAs reciprocally affect the self-assembly of nucleopeptides. In addition, the interactions between nucleopeptides and ssDNAs also decrease their proteolytic resistance against proteinase K, which further demonstrates the binding with ssDNAs. The nucleopeptides also interact with plasmid DNA and deliver hairpin DNA into cells. This work illustrates a new and rational approach to create soft biomaterials by the integration of nucleobases and peptides to bind with DNA, which may lead to the development of nucleopeptides for controlling DNA in cells.

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