The novel aciniform silk protein (AcSp2-v2) reveals the unique repetitive domain with high acid and thermal stability and self-assembly capability

AbstractIn the study reported herein, silver-coated copper (Ag/Cu) powder was modified with alkanethiols featuring alkyl chains of different lengths, namely butyl, octyl, and dodecyl, to improve its thermal stability. The modification of the Ag/Cu powders with adsorbed alkanethiols was confirmed by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. Each powder was combined with an epoxy resin to prepare an electrically conductive film. The results confirmed that the thermal stability of the films containing alkanethiol-modified Ag/Cu powders is superior to that of the film containing untreated Ag/Cu powder. The longer the alkyl group in the alkanethiol-modified Ag/Cu powder, the higher the initial resistance of the corresponding electrically conductive film and the lower the increase in resistance induced by heat treatment.

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Taming nitroformate through encapsulation with nitrogen-rich hydrogen-bonded organic frameworks

Nature Communications ◽

10.1038/s41467-021-22475-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Jichuan Zhang ◽

Yongan Feng ◽

Richard J. Staples ◽

Jiaheng Zhang ◽

Jean’ne M. Shreeve

Keyword(s):

Thermal Stability ◽

Hydrogen Bonds ◽

Self Assembly ◽

Energetic Materials ◽

Decomposition Temperature ◽

High Oxygen Content ◽

The Poor ◽

Simple Preparation ◽

First Time ◽

Hydrogen Bonded

AbstractOwing to its simple preparation and high oxygen content, nitroformate [−C(NO2)3, NF] is an extremely attractive oxidant component for propellants and explosives. However, the poor thermostability of NF-based derivatives has been an unconquerable barrier for more than 150 years, thus hindering its application. In this study, the first example of a nitrogen-rich hydrogen-bonded organic framework (HOF-NF) is designed and constructed through self-assembly in energetic materials, in which NF anions are trapped in pores of the resulting framework via the dual force of ionic and hydrogen bonds from the strengthened framework. These factors lead to the decomposition temperature of the resulting HOF-NF moiety being 200 °C, which exceeds the challenge of thermal stability over 180 °C for the first time among NF-based compounds. A large number of NF-based compounds with high stabilities and excellent properties can be designed and synthesized on the basis of this work.

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Hierarchical self-assembly of an azobenzene dyad with inverted amide connection into toroidal and tubular nanostructures

Organic & Biomolecular Chemistry ◽

10.1039/d0ob00833h ◽

2020 ◽

Vol 18 (21) ◽

pp. 3996-3999

Author(s):

Takuho Saito ◽

Shiki Yagai

Keyword(s):

Thermal Stability ◽

Self Assembly ◽

Supramolecular Chirality ◽

Thermal Stability Of

Inversion of the amide connectivity of an azobenzene dyad, which self-assembles into chiral toroids and nanotubes, improves the thermal stability of the assemblies, however it negatively affects supramolecular chirality.

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Cylindrical Micelles by the Self-Assembly of Crystalline-b-Coil Polyphosphazene-b-P2VP Block Copolymers. Stabilization of Gold Nanoparticles

Molecules ◽

10.3390/molecules24091772 ◽

2019 ◽

Vol 24 (9) ◽

pp. 1772 ◽

Cited By ~ 1

Author(s):

Maria de los Angeles Cortes ◽

Raquel de la Campa ◽

Maria Luisa Valenzuela ◽

Carlos Díaz ◽

Gabino A. Carriedo ◽

...

Keyword(s):

Gold Nanoparticles ◽

Block Copolymers ◽

Self Assembly ◽

Cationic Polymerization ◽

The Self ◽

The Novel ◽

Selective Solvent ◽

The Core ◽

Cylindrical Micelles ◽

Main Factor

During the last number of years a variety of crystallization-driven self-assembly (CDSA) processes based on semicrystalline block copolymers have been developed to prepare a number of different nanomorphologies in solution (micelles). We herein present a convenient synthetic methodology combining: (i) The anionic polymerization of 2-vinylpyridine initiated by organolithium functionalized phosphane initiators; (ii) the cationic polymerization of iminophosphoranes initiated by –PR2Cl2; and (iii) a macromolecular nucleophilic substitution step, to prepare the novel block copolymers poly(bistrifluoroethoxy phosphazene)-b-poly(2-vinylpyridine) (PTFEP-b-P2VP), having semicrystalline PTFEP core forming blocks. The self-assembly of these materials in mixtures of THF (tetrahydrofuran) and 2-propanol (selective solvent to P2VP), lead to a variety of cylindrical micelles of different lengths depending on the amount of 2-propanol added. We demonstrated that the crystallization of the PTFEP at the core of the micelles is the main factor controlling the self-assembly processes. The presence of pyridinyl moieties at the corona of the micelles was exploited to stabilize gold nanoparticles (AuNPs).

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Thermodynamically stable [4 + 2] cycloadducts of lanthanum-encapsulated endohedral metallofullerenes

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.10.65 ◽

2014 ◽

Vol 10 ◽

pp. 714-721 ◽

Cited By ~ 2

Author(s):

Yuta Takano ◽

Yuki Nagashima ◽

M Ángeles Herranz ◽

Nazario Martín ◽

Takeshi Akasaka

Keyword(s):

Thermal Stability ◽

Material Science ◽

Molecular Structures ◽

Spectroscopic Methods ◽

Dynamic Nmr ◽

The Novel ◽

Endohedral Metallofullerenes ◽

Derivatives Of ◽

Paramagnetic Properties

The [4 + 2] cycloaddition of o-quinodimethanes, generated in situ from the sultine 4,5-benzo-3,6-dihydro-1,2-oxathiin 2-oxide and its derivative, to La metal-encapsulated fullerenes, La2@C80 or La@C82, afforded the novel derivatives of endohedral metallofullerenes (3a,b, 4a,b and 5b). Molecular structures of the resulting compounds were elucidated using spectroscopic methods such as MALDI–TOF mass, optical absorption, and NMR spectroscopy. The [4 + 2] adducts of La2@C80 (3a,b, and 4a,b) and La@C82 (5b), respectively, retain diamagnetic and paramagnetic properties, as confirmed by EPR spectroscopy. Dynamic NMR measurements of 4a at various temperatures demonstrated the boat-to-boat inversions of the addend. In addition, 5b revealed remarkable thermal stability in comparison with the reported [4 + 2] cycloadduct of pentamethylcyclopentadiene and La@C82 (6). These findings demonstrate the utility of sultines to afford thermodynamically stable endohedral metallofullerene derivatives for the use in material science.

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The fractal self-assembly of the silk protein sericin

Soft Matter ◽

10.1039/b924530h ◽

2010 ◽

Vol 6 (9) ◽

pp. 2066 ◽

Cited By ~ 49

Author(s):

Tejas S. Khire ◽

Joydip Kundu ◽

Subhas C. Kundu ◽

Vamsi K. Yadavalli

Keyword(s):

Self Assembly ◽

Silk Protein

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Fabrication of montmorillonite and titanate nanotube based coatings via layer-by-layer self-assembly method to enhance the thermal stability, flame retardancy and ultraviolet protection of polyethylene terephthalate (PET) fabric

RSC Advances ◽

10.1039/c6ra05213d ◽

2016 ◽

Vol 6 (59) ◽

pp. 53625-53634 ◽

Cited By ~ 15

Author(s):

Ying Pan ◽

Wei Wang ◽

Haifeng Pan ◽

Jing Zhan ◽

Yuan Hu

Keyword(s):

Thermal Stability ◽

Polyethylene Terephthalate ◽

Flame Retardancy ◽

Self Assembly ◽

Layer By Layer ◽

Pet Fabric ◽

Thermal Oxidative Stability ◽

Titanate Nanotube ◽

Assembly Method ◽

Ultraviolet Protection

Montmorillonite and titanate nanotube based coatings have been prepared through LbL self-assembly method, in order to enhance the thermal and thermal-oxidative stability, flame retardancy and UV protection of polyethylene terephthalate fabric.

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Low-temperature hydrothermal synthesis of hierarchical flower-like CuB2O4 superstructures

Processing and Application of Ceramics ◽

10.2298/pac2002113u ◽

2020 ◽

Vol 14 (2) ◽

pp. 113-118

Author(s):

Daniel Ursu ◽

Anamaria Dabici ◽

Marinela Miclau ◽

Nicolae Miclau

Keyword(s):

Thermal Stability ◽

Low Temperature ◽

Self Assembly ◽

Hydrothermal Solution ◽

Optical Measurements ◽

Oriented Attachment ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

One Step

We report for the first time the fabrication of hierarchical ordered superstructure CuB2O4 with flower-like morphology via a one-step, low temperature hydrothermal method. The tetragonal structure of CuB2O4 was determined by X-ray diffraction and high-resolution transmission electron microscopy. Optical measurements attested of the quality of the fabricated CuB2O4 and high temperature X-ray diffraction confirmed its thermal stability up to 600 ?C. The oriented attachment growth and the hierarchical self-assembly of micrometer-sized platelets producing hierarchical superstructures with flower-like morphology are designed by pH of the hydrothermal solution. The excellent band gap, high thermal stability and hierarchical structure of the CuB2O4 are promising for the photovoltaic and photocatalytic applications.

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Self-Assembled Metal–Organic Biohybrids (MOBs) Using Copper and Silver for Cell Studies

Nanomaterials ◽

10.3390/nano9091282 ◽

2019 ◽

Vol 9 (9) ◽

pp. 1282 ◽

Cited By ~ 3

Author(s):

Neha Karekar ◽

Anik Karan ◽

Elnaz Khezerlou ◽

Neela Prajapati ◽

Chelsea D. Pernici ◽

...

Keyword(s):

Self Assembly ◽

Neuroblastoma Cells ◽

The Novel ◽

Culture Methods ◽

Synthesis Conditions ◽

Tissue Constructs ◽

Silver Sulfate ◽

Significant Toxicity ◽

Metal Organic

The novel synthesis of metal-containing biohybrids using self-assembly methods at physiological temperatures (37 °C) was compared for copper and silver using the amino acid dimer cystine. Once assembled, the copper containing biohybrid is a stable, high-aspect ratio structure, which we call CuHARS. Using the same synthesis conditions, but replacing copper with silver, we have synthesized cystine-capped silver nanoparticles (AgCysNPs), which are shown here to form stable colloid solutions in contrast to the CuHARS, which settle out from a 1 mg/mL solution in 90 min. Both the copper and silver biohybrids, as synthesized, demonstrate very low agglomeration which we have applied for the purpose of applications with cell culture methods, namely, for testing as anti-cancer compounds. AgCysNPs (1000 ng/mL) demonstrated significant toxicity (only 6.8% viability) to glioma and neuroblastoma cells in vitro, with concentrations as low as 20 ng/mL causing some toxicity. In contrast, CuHARS required at least 5 μg/mL. For comparative purposes, silver sulfate at 100 ng/mL decreased viability by 52% and copper sulfate at 100 ng/mL only by 19.5% on glioma cells. Using these methods, the novel materials were tested here as metal–organic biohybrids (MOBs), and it is anticipated that the functionalization and dynamics of MOBs may result in building a foundation of new materials for cellular applications, including cell engineering of both normal and diseased cells and tissue constructs.

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