Self-assembly and properties of low-dimensional nanomaterials based on π-conjugated organic molecules

Building supramolecular architectures with well-defined shapes and functions is of great importance in materials science, nanochemistry, and biomimetic chemistry. In recent years, we have devoted much effort to the construction of well-defined supramolecular structures through noncovalent forces such as hydrogen bonding, π-stacking, metal-ligand bonds, and hydrophilic and hydrophobic interactions, with the aid of functional building blocks. The morphologies and their physical properties were studied, and new methods for the construction of one-dimensional nanoscale structures have been developed. In this review, we summarize our recent studies on the design and synthesis of the supramolecular systems, as well as the physical properties of nanoscale structures.

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Towards Building Blocks for Supramolecular Architectures Based on Azacryptates

Molecules ◽

10.3390/molecules25071733 ◽

2020 ◽

Vol 25 (7) ◽

pp. 1733 ◽

Cited By ~ 1

Author(s):

Ana Miljkovic ◽

Sonia La Cognata ◽

Greta Bergamaschi ◽

Mauro Freccero ◽

Antonio Poggi ◽

...

Keyword(s):

Conformational Changes ◽

Self Assembly ◽

Hydrophobic Interactions ◽

Building Blocks ◽

Water Mixture ◽

Molecular Systems ◽

Supramolecular Architectures ◽

Starting Point ◽

The Difference ◽

Supramolecular Devices

In this work, we report the synthesis of a new bis(tris(2-aminoethyl)amine) azacryptand L with triphenyl spacers. The binding properties of its dicopper complex for aromatic dicarboxylate anions (as TBA salts) were investigated, with the aim to obtain potential building blocks for supramolecular structures like rotaxanes and pseudo-rotaxanes. As expected, UV-Vis and emission studies of [Cu2L]4+ in water/acetonitrile mixture (pH = 7) showed a high affinity for biphenyl-4,4′-dicarboxylate (dfc2−), with a binding constant of 5.46 log units, due to the best match of the anion bite with the Cu(II)-Cu(II) distance in the cage’s cavity. Compared to other similar bistren cages, the difference of the affinity of [Cu2L]4+ for the tested anions was not so pronounced: conformational changes of L seem to promote a good interaction with both long (e.g., dfc2−) and short anions (e.g., terephthalate). The good affinity of [Cu2L]4+ for these dicarboxylates, together with hydrophobic interactions within the cage’s cavity, may promote the self-assembly of a stable 1:1 complex in water mixture. These results represent a good starting point for the application of these molecular systems as building units for the design of new supramolecular architectures based on non-covalent interactions, which could be of interest in all fields related to supramolecular devices.

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Assembling Photo- and Electroresponsive Molecules and Nano-Objects

MRS Bulletin ◽

10.1557/mrs2007.106 ◽

2007 ◽

Vol 32 (7) ◽

pp. 556-560 ◽

Cited By ~ 3

Author(s):

Michael Busby ◽

Luisa De Cola ◽

Gregg S. Kottas ◽

Zoran Popović

Keyword(s):

Self Assembly ◽

Building Blocks ◽

Supramolecular Systems ◽

Natural Systems ◽

Design And Synthesis ◽

Zeolite L ◽

Solid Substrates ◽

Potential Applications ◽

Collective Interactions ◽

Spectroscopic Behavior

The self-assembly of small molecules into large, functional nanostructures has led to the construction of supramolecular systems, both in solution and on solid substrates, with defined dimensions that display unique properties through collective interactions, much like natural systems. In this article, we show how one assembles photo- and electroluminescent molecules through coordination chemistry for the purpose of producing novel materials that can be used for displays and lighting applications. In a stepwise process, we discuss the design and synthesis of the components, their spectroscopic behavior, and finally the properties arising from the assembly. We then move from molecules to more complex systems such as zeolite L nano-objects that can be used as nanocontainers and functionalized in different ways. We show how it is possible to organize rods of micron length in a geometrically controlled manner in solution and on surfaces. The assemblies are built by coordinative bonds and are luminescent materials that can be constructed from fluorescent building blocks, with potential applications as optoelectronic materials, in analogy to their molecular counterparts.

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Nanoscale Crystalline Sheets and Vesicles Assembled from Nonplanar Cyclic π-Conjugated Molecules

Research ◽

10.34133/2019/1953926 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Huang Tang ◽

Zhewei Gu ◽

Haifeng Ding ◽

Zhibo Li ◽

Shiyan Xiao ◽

...

Keyword(s):

Self Assembly ◽

Carbon Nanomaterials ◽

Materials Science ◽

Functional Materials ◽

Building Blocks ◽

Molecular Scaffolds ◽

Conjugated Molecules ◽

New Class ◽

Supramolecular Architectures ◽

Cyclic Molecules

A fundamental challenge in chemistry and materials science is to create new carbon nanomaterials by assembling structurally unique carbon building blocks, such as nonplanar π-conjugated cyclic molecules. However, self-assembly of such cyclic π-molecules to form organized nanostructures has been rarely explored despite intensive studies on their chemical synthesis. Here we synthesized a family of new cycloparaphenylenes and found that these fully hydrophobic and nonplanar cyclic π-molecules could self-assemble into structurally distinct two-dimensional crystalline multilayer nanosheets. Moreover, these crystalline multilayer nanosheets could overcome inherent rigidity to curve into closed crystalline vesicles in solution. These supramolecular assemblies show that the cyclic molecular scaffolds are homogeneously arranged on the surface of nanosheets and vesicles with their molecular isotropic x-y plane standing obliquely on the surface. These supramolecular architectures that combined exact crystalline order, orientation-specific arrangement of π-conjugated cycles, controllable morphology, uniform molecular pore, superior florescence quench ability, and photoluminescence are expected to give rise to a new class of functional materials displaying unique photonic, electronic, and biological functions.

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DNA-based self-assembly of nanostructures

10.1093/oxfordhb/9780199533053.013.24 ◽

2017 ◽

Author(s):

Joshua D. Carter ◽

Chenxiang Lin ◽

Yan Liu ◽

Hao Yan ◽

Thomas H. LaBean

Keyword(s):

Self Assembly ◽

Materials Science ◽

Directed Assembly ◽

Building Blocks ◽

Hierarchical Assembly ◽

Synthetic Dna ◽

Nanoscale Manufacturing ◽

Covalently Linked ◽

Design Construction ◽

Proteins And Peptides

This article examines the DNA-based self-assembly of nanostructures. It first reviews the development of DNA self-assembly and DNA-directed assembly, focusing on the main strategies and building blocks available in the modern molecular construction toolbox, including the design, construction, and analysis of nanostructures composed entirely of synthetic DNA, as well as origami nanostructures formed from a mixture of synthetic and biological DNA. In particular, it considers the stepwise covalent synthesis of DNA nanomaterials, unmediated assembly of DNA nanomaterials, hierarchical assembly, nucleated assembly, and algorithmic assembly. It then discusses DNA-directed assembly of heteromaterials such as proteins and peptides, gold nanoparticles, and multicomponent nanostructures. It also describes the use of complementary DNA cohesion as 'smart glue' for bringing together covalently linked functional groups, biomolecules, and nanomaterials. Finally, it evaluates the potential future of DNA-based self-assembly for nanoscale manufacturing for applications in medicine, electronics, photonics, and materials science.

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Zeolates: A Coordination Chemistry View of Metal-Ligand Bonding in Intrazeolite MOCVD Type Precursors and Semiconductor Nanoclusters

MRS Proceedings ◽

10.1557/proc-277-105 ◽

1992 ◽

Vol 277 ◽

Cited By ~ 6

Author(s):

Geoffrey A. Ozin ◽

Carol L. Bowes ◽

Mark R. Steele

Keyword(s):

Self Assembly ◽

Materials Science ◽

Zeolite Y ◽

Chemical Vapour ◽

Internal Surface ◽

Building Blocks ◽

Structural Features ◽

Organic Chemical ◽

Wide Range ◽

Shape Selective

ABSTRACTVarious MOCVD (metal-organic chemical vapour deposition) type precursors and their self-assembled semiconductor nanocluster products [1] have been investigated in zeolite Y hosts. From analysis of in situ observations (FTIR, UV-vis reflectance, Mössbauer, MAS-NMR) of the reaction sequences and structural features of the precursors and products (EXAFS and Rietveld refinement of powder XRD data) the zeolite is viewed as providing a macrospheroidal, multidendate coordination environment towards encapsulated guests. By thinking about the α- and β-cages of the zeolite Y host effectively as a zeolate ligand composed of interconnected aluminosilicate “crown ether-like” building blocks, the materials chemist is able to better understand and exploit the reactivity and coordination properties of the zeolite internal surface for the anchoring and self-assembly of a wide range of encapsulated guests. This approach helps with the design of synthetic strategies for creating novel guest-host inclusion compounds having possible applications in areas of materials science such as nonlinear optics, quantum electronics, and size/shape selective catalysis.

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Self Assembling Nanostructured Delivery Vehicles for Biochemically Reactive Pairs

MRS Proceedings ◽

10.1557/proc-351-109 ◽

1994 ◽

Vol 351 ◽

Author(s):

Nir Kossovsky ◽

A. Gelman ◽

H.J. Hnatyszyn ◽

E. Sponsler ◽

G.-M. Chow

Keyword(s):

Physical Properties ◽

Self Assembly ◽

Materials Science ◽

Technology Development ◽

Biological Behavior ◽

X Ray Diffraction ◽

Self Assembling ◽

Transmission Electron ◽

Carbon Ceramic

ABSTRACTIntrigued by the deceptive simplicity and beauty of macromolecular self-assembly, our laboratory began studying models of self-assembly using solids, glasses, and colloidal substrates. These studies have defined a fundamental new colloidal material for supporting members of a biochemically reactive pair.The technology, a molecular transportation assembly, is based on preformed carbon ceramic nanoparticles and self assembled calcium-phosphate dihydrate particles to which glassy carbohydrates are then applied as a nanometer thick surface coating. This carbohydrate coated core functions as a dehydroprotectant and stabilizes surface immobilized members of a biochemically reactive pair. The final product, therefore, consists of three layers. The core is comprised of the ceramic, the second layer is the dehydroprotectant carbohydrate adhesive, and the surface layer is the biochemically reactive molecule for which delivery is desired.We have characterized many of the physical properties of this system and have evaluated the utility of this delivery technology in vitro and in animal models. Physical characterization has included standard and high resolution transmission electron microscopy, electron and x-ray diffraction and ζ potential analysis. Functional assays of the ability of the system to act as a nanoscale dehydroprotecting delivery vehicle have been performed on viral antigens, hemoglobin, and insulin. By all measures at present, the favorable physical properties and biological behavior of the molecular transportation assembly point to an exciting new interdisciplinary area of technology development in materials science, chemistry and biology.

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Modification of a Single Atom Affects the Physical Properties of Double Fluorinated Fmoc-Phe Derivatives

International Journal of Molecular Sciences ◽

10.3390/ijms22179634 ◽

2021 ◽

Vol 22 (17) ◽

pp. 9634

Author(s):

Moran Aviv ◽

Dana Cohen-Gerassi ◽

Asuka A. Orr ◽

Rajkumar Misra ◽

Zohar A. Arnon ◽

...

Keyword(s):

Amino Acid ◽

Physical Properties ◽

Self Assembly ◽

Deep Understanding ◽

Building Blocks ◽

The Self ◽

Single Atom ◽

Supramolecular Organization ◽

Assembly Process ◽

Wide Range

Supramolecular hydrogels formed by the self-assembly of amino-acid based gelators are receiving increasing attention from the fields of biomedicine and material science. Self-assembled systems exhibit well-ordered functional architectures and unique physicochemical properties. However, the control over the kinetics and mechanical properties of the end-products remains puzzling. A minimal alteration of the chemical environment could cause a significant impact. In this context, we report the effects of modifying the position of a single atom on the properties and kinetics of the self-assembly process. A combination of experimental and computational methods, used to investigate double-fluorinated Fmoc-Phe derivatives, Fmoc-3,4F-Phe and Fmoc-3,5F-Phe, reveals the unique effects of modifying the position of a single fluorine on the self-assembly process, and the physical properties of the product. The presence of significant physical and morphological differences between the two derivatives was verified by molecular-dynamics simulations. Analysis of the spontaneous phase-transition of both building blocks, as well as crystal X-ray diffraction to determine the molecular structure of Fmoc-3,4F-Phe, are in good agreement with known changes in the Phe fluorination pattern and highlight the effect of a single atom position on the self-assembly process. These findings prove that fluorination is an effective strategy to influence supramolecular organization on the nanoscale. Moreover, we believe that a deep understanding of the self-assembly process may provide fundamental insights that will facilitate the development of optimal amino-acid-based low-molecular-weight hydrogelators for a wide range of applications.

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ChemInform Abstract: Design and Synthesis of Porphyrins Bearing Rigid Hydrogen Bonding Motifs: Highly Versatile Building Blocks for Self-Assembly of Polymers and Discrete Arrays.

ChemInform ◽

10.1002/chin.200211099 ◽

2010 ◽

Vol 33 (11) ◽

pp. no-no

Author(s):

Xinxu Shi ◽

Kathleen M. Barkigia ◽

Jack Fajer ◽

Charles Michael Drain

Keyword(s):

Hydrogen Bonding ◽

Self Assembly ◽

Building Blocks ◽

Design And Synthesis

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Controlling the Self-Assembly of Biomolecules into Functional Nanomaterials through Internal Interactions and External Stimulations: A Review

Nanomaterials ◽

10.3390/nano9020285 ◽

2019 ◽

Vol 9 (2) ◽

pp. 285 ◽

Cited By ~ 30

Author(s):

Li Wang ◽

Coucong Gong ◽

Xinzhu Yuan ◽

Gang Wei

Keyword(s):

Self Assembly ◽

Electrostatic Interactions ◽

Materials Science ◽

Hydrophobic Interactions ◽

The Self ◽

Functional Nanomaterials ◽

Light Stimulation ◽

Dna Base ◽

Wide Range ◽

Structure And Functions

Biomolecular self-assembly provides a facile way to synthesize functional nanomaterials. Due to the unique structure and functions of biomolecules, the created biological nanomaterials via biomolecular self-assembly have a wide range of applications, from materials science to biomedical engineering, tissue engineering, nanotechnology, and analytical science. In this review, we present recent advances in the synthesis of biological nanomaterials by controlling the biomolecular self-assembly from adjusting internal interactions and external stimulations. The self-assembly mechanisms of biomolecules (DNA, protein, peptide, virus, enzyme, metabolites, lipid, cholesterol, and others) related to various internal interactions, including hydrogen bonds, electrostatic interactions, hydrophobic interactions, π–π stacking, DNA base pairing, and ligand–receptor binding, are discussed by analyzing some recent studies. In addition, some strategies for promoting biomolecular self-assembly via external stimulations, such as adjusting the solution conditions (pH, temperature, ionic strength), adding organics, nanoparticles, or enzymes, and applying external light stimulation to the self-assembly systems, are demonstrated. We hope that this overview will be helpful for readers to understand the self-assembly mechanisms and strategies of biomolecules and to design and develop new biological nanostructures or nanomaterials for desired applications.

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