The self-assembly of a low symmetric aromatic carboxylic acid with meta-carboxyl groups regulated by pyridine derivatives

The self-assembly structures of 2,2[Formula: see text]:6[Formula: see text],2[Formula: see text]-terpyridine-4[Formula: see text]-carboxylic acid (C[Formula: see text]H[Formula: see text]N3O2; [Formula: see text]) molecules and 3,5-diphenylbenzoic acid (C[Formula: see text]H[Formula: see text]O2; [Formula: see text]) molecules on Ag(110) surface have been investigated by scanning tunneling microscopy (STM) and Density Functional Theory (DFT) calculation. The [Formula: see text] molecules form two different well-organized structures due to the [Formula: see text]–[Formula: see text] stacking and dipole–dipole interactions. When three C atoms of [Formula: see text] molecules are replaced by three N atoms to form [Formula: see text] molecules, the main driving force to form ordered assembly structures of [Formula: see text] molecule is changed to metal–organic coordination bond and hydrogen bond. The dramatic changes of main driving force between [Formula: see text]/Ag(110) and [Formula: see text]/Ag(110) system demonstrate that the N atoms are apt to form metal–organic coordination bond and hydrogen bond but dipole–dipole interactions and [Formula: see text]–[Formula: see text] stacking are relative to C atoms. These findings further reveal that the optimization design of organic molecules could vary the main driving force and then lead to the change of the molecular self-assembly structures.

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Effect of solvent, pH and metal ions on the self-assembly process and optical properties of an A–π–D–π–A type triphenylamine carboxylic acid derivative

Journal of Materials Chemistry C ◽

10.1039/c5tc03351a ◽

2016 ◽

Vol 4 (14) ◽

pp. 2990-3001 ◽

Cited By ~ 4

Author(s):

Lin Kong ◽

Yun Liu ◽

Hui Wang ◽

Xiao-he Tian ◽

Qi-yu Chen ◽

...

Keyword(s):

Optical Properties ◽

Carboxylic Acid ◽

Metal Ions ◽

Acid Derivative ◽

Self Assembly ◽

Metal Ion ◽

The Self ◽

Assembly Process ◽

Effect Of Solvent ◽

Carboxylic Acid Derivative

The effect of solvent, pH and metal ion on the morphology and optical properties of a carboxylic-acid derivative was researched.

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The Nature of Rapidly Extracted Phycocyanin from the Blue-Green Alga Plectonema Boryanum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065870 ◽

1971 ◽

Vol 29 ◽

pp. 366-367

Author(s):

M. Kessel ◽

R. MacColl

Keyword(s):

Self Assembly ◽

Analytical Ultracentrifugation ◽

Uranyl Acetate ◽

The Self ◽

Major Protein ◽

Subunit Structure ◽

Blue Green Alga ◽

Thin Sections ◽

Blue Green Algae ◽

Cacodylate Buffer

The major protein of the blue-green algae is the biliprotein, C-phycocyanin (Amax = 620 nm), which is presumed to exist in the cell in the form of distinct aggregates called phycobilisomes. The self-assembly of C-phycocyanin from monomer to hexamer has been extensively studied, but the proposed next step in the assembly of a phycobilisome, the formation of 19s subunits, is completely unknown. We have used electron microscopy and analytical ultracentrifugation in combination with a method for rapid and gentle extraction of phycocyanin to study its subunit structure and assembly.To establish the existence of phycobilisomes, cells of P. boryanum in the log phase of growth, growing at a light intensity of 200 foot candles, were fixed in 2% glutaraldehyde in 0.1M cacodylate buffer, pH 7.0, for 3 hours at 4°C. The cells were post-fixed in 1% OsO4 in the same buffer overnight. Material was stained for 1 hour in uranyl acetate (1%), dehydrated and embedded in araldite and examined in thin sections.

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Interrelationship of the cellular distribution and secretion of regular structure (RS) protein in Bacillus licheniformis nm 105

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123969 ◽

1992 ◽

Vol 50 (1) ◽

pp. 712-713

Author(s):

Xiaorong Zhu ◽

Richard McVeigh ◽

Bijan K. Ghosh

Keyword(s):

Alkaline Phosphatase ◽

Bacillus Licheniformis ◽

Self Assembly ◽

Gel Electrophoresis ◽

Culture Supernatant ◽

Regular Structure ◽

The Self ◽

Cellular Distribution ◽

Structural Protein ◽

Laboratory Cultures

A mutant of Bacillus licheniformis 749/C, NM 105 exhibits some notable properties, e.g., arrest of alkaline phosphatase secretion and overexpression and hypersecretion of RS protein. Although RS is known to be widely distributed in many microbes, it is rarely found, with a few exceptions, in laboratory cultures of microorganisms. RS protein is a structural protein and has the unusual properties to form aggregate. This characteristic may have been responsible for the self assembly of RS into regular tetragonal structures. Another uncommon characteristic of RS is that enhanced synthesis and secretion which occurs when the cells cease to grow. Assembled RS protein with a tetragonal structure is not seen inside cells at any stage of cell growth including cells in the stationary phase of growth. Gel electrophoresis of the culture supernatant shows a very large amount of RS protein in the stationary culture of the B. licheniformis. It seems, Therefore, that the RS protein is cotranslationally secreted and self assembled on the envelope surface.

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Nanoscale Self-Assembly Using Ion and Electron Beam Techniques: A Rapid Review

MRS Advances ◽

10.1557/adv.2020.349 ◽

2020 ◽

Vol 5 (64) ◽

pp. 3507-3520

Author(s):

Chunhui Dai ◽

Kriti Agarwal ◽

Jeong-Hyun Cho

Keyword(s):

Electron Beam ◽

Self Assembly ◽

Ion Beam ◽

Three Dimensional ◽

The Self ◽

Stress Generation ◽

Rapid Review ◽

High Yield ◽

3D Nanostructures ◽

Self Assembled

AbstractNanoscale self-assembly, as a technique to transform two-dimensional (2D) planar patterns into three-dimensional (3D) nanoscale architectures, has achieved tremendous success in the past decade. However, an assembly process at nanoscale is easily affected by small unavoidable variations in sample conditions and reaction environment, resulting in a low yield. Recently, in-situ monitored self-assembly based on ion and electron irradiation has stood out as a promising candidate to overcome this limitation. The usage of ion and electron beam allows stress generation and real-time observation simultaneously, which significantly enhances the controllability of self-assembly. This enables the realization of various complex 3D nanostructures with a high yield. The additional dimension of the self-assembled 3D nanostructures opens the possibility to explore novel properties that cannot be demonstrated in 2D planar patterns. Here, we present a rapid review on the recent achievements and challenges in nanoscale self-assembly using electron and ion beam techniques, followed by a discussion of the novel optical properties achieved in the self-assembled 3D nanostructures.

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Bottom-up Evolution from Disks to High-Genus Polymersomes

10.26434/chemrxiv.6108467.v1 ◽

2018 ◽

Author(s):

Claudia Contini ◽

Russell Pearson ◽

Linge Wang ◽

Lea Messager ◽

Jens Gaitzsch ◽

...

Keyword(s):

Self Assembly ◽

The Self ◽

Amphiphilic Copolymers ◽

Chain Entanglement ◽

Bottom Up ◽

New Approach ◽

High Genus ◽

Transmission Electron ◽

Minimal Radius ◽

Stop Flow

<div><div><div><p>We report the design of polymersomes using a bottom-up approach where the self-assembly of amphiphilic copolymers poly(2-(methacryloyloxy) ethyl phosphorylcholine)–poly(2-(diisopropylamino) ethyl methacrylate) (PMPC-PDPA) into membranes is tuned using pH and temperature. We study this process in detail using transmission electron microscopy (TEM), nuclear magnetic resonance (NMR) spectroscopy, dynamic light scattering (DLS), and stop-flow ab- sorbance disclosing the molecular and supramolecular anatomy of each structure observed. We report a clear evolution from disk micelles to vesicle to high-genus vesicles where each passage is controlled by pH switch or temperature. We show that the process can be rationalised adapting membrane physics theories disclosing important scaling principles that allow the estimation of the vesiculation minimal radius as well as chain entanglement and coupling. This allows us to propose a new approach to generate nanoscale vesicles with genus from 0 to 70 which have been very elusive and difficult to control so far.</p></div></div></div>

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Bottom-up Evolution from Disks to High-Genus Polymersomes

10.26434/chemrxiv.6108467 ◽

2018 ◽

Author(s):

Claudia Contini ◽

Russell Pearson ◽

Linge Wang ◽

Lea Messager ◽

Jens Gaitzsch ◽

...

Keyword(s):

Self Assembly ◽

The Self ◽

Amphiphilic Copolymers ◽

Chain Entanglement ◽

Bottom Up ◽

New Approach ◽

High Genus ◽

Transmission Electron ◽

Minimal Radius ◽

Stop Flow

<div><div><div><p>We report the design of polymersomes using a bottom-up approach where the self-assembly of amphiphilic copolymers poly(2-(methacryloyloxy) ethyl phosphorylcholine)–poly(2-(diisopropylamino) ethyl methacrylate) (PMPC-PDPA) into membranes is tuned using pH and temperature. We study this process in detail using transmission electron microscopy (TEM), nuclear magnetic resonance (NMR) spectroscopy, dynamic light scattering (DLS), and stop-flow ab- sorbance disclosing the molecular and supramolecular anatomy of each structure observed. We report a clear evolution from disk micelles to vesicle to high-genus vesicles where each passage is controlled by pH switch or temperature. We show that the process can be rationalised adapting membrane physics theories disclosing important scaling principles that allow the estimation of the vesiculation minimal radius as well as chain entanglement and coupling. This allows us to propose a new approach to generate nanoscale vesicles with genus from 0 to 70 which have been very elusive and difficult to control so far.</p></div></div></div>

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