Bottom-up Evolution from Disks to High-Genus Polymersomes

<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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Amphiphilic Nucleobase-Containing Polypeptide Copolymers—Synthesis and Self-Assembly

Polymers ◽

10.3390/polym12061357 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1357

Author(s):

Michel Nguyen ◽

Khalid Ferji ◽

Sébastien Lecommandoux ◽

Colin Bonduelle

Keyword(s):

Self Assembly ◽

Ring Opening ◽

Building Blocks ◽

Ring Opening Polymerization ◽

The Self ◽

Amphiphilic Copolymers ◽

Transmission Electron ◽

Scattering Measurements ◽

Thymidine Monophosphate ◽

The Impact

Nucleobase-containing polymers are an emerging class of building blocks for the self-assembly of nanoobjects with promising applications in nanomedicine and biology. Here we present a macromolecular engineering approach to design nucleobase-containing polypeptide polymers incorporating thymine that further self-assemble in nanomaterials. Diblock and triblock copolypeptide polymers were prepared using sequential ring-opening polymerization of γ-Benzyl-l-glutamate N-carboxyanhydride (BLG-NCA) and γ-Propargyl-l-glutamate N-carboxyanhydride (PLG-NCA), followed by an efficient copper(I)-catalyzed azide alkyne cycloaddition (CuAAc) functionalization with thymidine monophosphate. Resulting amphiphilic copolymers were able to spontaneously form nanoobjects in aqueous solutions avoiding a pre-solubilization step with an organic solvent. Upon self-assembly, light scattering measurements and transmission electron microscopy (TEM) revealed the impact of the architecture (diblock versus triblock) on the morphology of the resulted nanoassemblies. Interestingly, the nucleobase-containing nanoobjects displayed free thymine units in the shell that were found available for further DNA-binding.

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Azobenzene-functionalized graphene nanoribbons: bottom-up synthesis, photoisomerization behaviour and self-assembled structures

Journal of Materials Chemistry C ◽

10.1039/d0tc01609h ◽

2020 ◽

Vol 8 (31) ◽

pp. 10837-10843

Author(s):

Zhichun Shangguan ◽

Chunyang Yu ◽

Chen Li ◽

Xianhui Huang ◽

Yiyong Mai ◽

...

Keyword(s):

Self Assembly ◽

Graphene Nanoribbons ◽

The Self ◽

Functionalized Graphene ◽

Bottom Up ◽

Self Assembled ◽

Azobenzene Groups

We show the strategy of introducing azobenzene groups into graphene nanoribbons (GNRs), which not only endows GNRs with fast photo-responsiveness but also induces the self-assembly of the GNRs into ultra-long nanowires.

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Block Copolymer Films Hierarchical Assembly in Confinement

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.364-366.437 ◽

2007 ◽

Vol 364-366 ◽

pp. 437-441

Author(s):

Yong Zhi Cao ◽

Shen Dong ◽

Ying Chun Liang ◽

Tao Sun ◽

Yong Da Yan

Keyword(s):

Block Copolymer ◽

Self Assembly ◽

Structural Control ◽

Computer Control ◽

The Self ◽

Top Down ◽

Bottom Up ◽

Dimensional Precision ◽

Periodic Arrays ◽

Copolymer Films

Ultrathin block copolymer films are promising candidates for bottom-up nanotemplates in hybrid organic-inorganic electronic, optical, and magnetic devices. Key to many future applications is the long range ordering and precise placement of the phase-separated nanoscale domains. In this paper, a combined top-down/bottom-up hierarchical approach is presented on how to fabricate massive arrays of aligned nanoscale domains by means of the self-assembly of asymmetric poly (styrene-block-ethylene/butylenes-block-styrene) (SEBS) tirblock copolymers in confinement. The periodic arrays of the poly domains were orientated via the introduction of AFM micromachining technique as a tool for locally controlling the self-assembly process of triblock copolymers by the topography of the silicon nitride substrate. Using the controlled movement of 2- dimensional precision stage and the micro pressure force between the tip and the surface by computer control system, an artificial topographic pattern on the substrate can be fabricated precisely. Coupled with solvent annealing technique to direct the assembly of block copolymer, this method provides new routes for fabricating ordered nanostructure. This graphoepitaxial methodology can be exploited in hybrid hard/soft condensed matter systems for a variety of applications. Moreover, Pairing top-down and bottom-up techniques is a promising, and perhaps necessary, bridge between the parallel self-assembly of molecules and the structural control of current technology.

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Towards supramolecular nanostructured materials: control of the self-assembly of ionic bent-core amphiphiles

Journal of Materials Chemistry C ◽

10.1039/c9tc06002b ◽

2020 ◽

Vol 8 (6) ◽

pp. 1998-2007 ◽

Cited By ~ 2

Author(s):

Martín Castillo-Vallés ◽

Miguel Cano ◽

Ana Bermejo-Sanz ◽

Nélida Gimeno ◽

M. Blanca Ros

Keyword(s):

Nanostructured Materials ◽

Self Assembly ◽

Molecular Design ◽

The Self ◽

Bottom Up

Bottom-up self-assembly: the formation of mesophases and nanostructures in solution from ionic bent-core dendrimers has been systematically studied by molecular design.

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Self-assembly of amphiphilic copolymers containing polysaccharide: PISA versus nanoprecipitation, and the temperature effect

Polymer Chemistry ◽

10.1039/d0py00407c ◽

2020 ◽

Vol 11 (29) ◽

pp. 4729-4740 ◽

Cited By ~ 1

Author(s):

Djallal Ikkene ◽

Ana Andreea Arteni ◽

Malika Ouldali ◽

Jean-Luc Six ◽

Khalid Ferji

Keyword(s):

Temperature Effect ◽

Self Assembly ◽

The Self ◽

Amphiphilic Copolymers ◽

Considerable Impact

The self-assembly methods and the temperature have a considerable impact on the morphology of the resulting nanoobjects in the case of amphiphilic glycopolymers.

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Fabrication and Properties of Self-Assembled Nanosized Magnetic Particles

MRS Proceedings ◽

10.1557/proc-707-w7.1.1 ◽

2001 ◽

Vol 707 ◽

Cited By ~ 3

Author(s):

G. Salazar-Alvarez ◽

M. Mikhailova ◽

M. Toprak ◽

Y. Zhang ◽

M. Muhammed

Keyword(s):

Self Assembly ◽

Magnetic Particles ◽

Average Particle Size ◽

The Self ◽

Average Particle ◽

Shell Nanoparticles ◽

Force Microscopy ◽

Transmission Electron ◽

Self Assembled ◽

Core Shell Nanoparticles

ABSTRACTThe synthesis and characterisation of gold-coated cobalt nanoparticles, as well as their chemically- and magnetically-induced self-organisation have been studied. Metallic core-shell nanoparticles were prepared using two different experimental techniques: bulk reductive precipitation, with average particles size ∼15 nm, and microemulsion confining method, with average particle size of ∼6 nm. The self-assembly of prepared nanoparticles on flat substrates was achieved by derivatising the substrate and particle surfaces with bifunctional organic molecules that attaches to both particles and substrates. Examination of the self-assembled systems was carried out by a number of characterisation techniques including transmission electron microscopy (TEM), UV-visible spectrophotometry (UV-VIS), and atomic force microscopy (AFM).

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Self-Organizing Tree Using Artificial Ants

Interdisciplinary Advances in Information Technology Research ◽

10.4018/978-1-4666-3625-5.ch005 ◽

2013 ◽

pp. 60-74

Author(s):

Hanene Azzag ◽

Mustapha Lebbah

Keyword(s):

Self Assembly ◽

The Self ◽

Hierarchical Partitioning ◽

Hierarchical Tree ◽

New Approach ◽

Hierarchical Relations ◽

Artificial Ants ◽

Inherent Structure ◽

Assembly Behavior ◽

Self Organizing

In this paper, the authors propose a new approach for topological hierarchical tree clustering inspired from the self-assembly behavior of artificial ants. The method, called SoTree (Self-organizing Tree), builds, autonomously and simultaneously, a topological and hierarchical partitioning of data. Each ’’cluster’’ associated to one cell of a 2D grid is modeled by a tree. The artificial ants similarly build a tree where each ant represents a node/data. The benefit of this approach is the intuitive representation of hierarchical relations in the data. This is especially appealing in explorative data mining applications, allowing the inherent structure of the data to unfold in a highly intuitive fashion.

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Hematite Nano Cubes and the Prototypes of Their Self Assembly Investigated Using Tem

MRS Proceedings ◽

10.1557/proc-432-183 ◽

1996 ◽

Vol 432 ◽

Cited By ~ 1

Author(s):

San Yu ◽

Shihai Kan ◽

Guangtian Zou ◽

Xiaogang Peng ◽

Dongmei Li ◽

...

Keyword(s):

Aqueous Solution ◽

Self Assembly ◽

Short Range ◽

The Self ◽

Magnetic Feature ◽

Preferential Growth ◽

Single Crystalline ◽

Transmission Electron ◽

Assembly Feature ◽

Equilibrium Shapes

AbstractMonodisperse hematite cubes about 30nm in size have been prepared by aging a refluxing acidified aqueous solution of FeCl3 in an open vessel. The as grown nano cubes were determined to be single crystalline hematite in perfect cubic shapes using transmission electron microscope and electron diffraction. The nano cube is one of the equilibrium shapes of hematite, which is resumed to be formed by preferential growth in certain crystallographic directions through the species diffusion in the aqueous solutions.Some self-assembly prototypes have been observed, such as the short range ordered buildup consisting of several brick-like hematite nano cubes and the nano box consisted of square plates of hematite nanocrystals. The drive force for the formation of the above assemblies is assumed to be the unique magnetic feature of the single crystalline hematite nano cubes.The perfect shape and the self-assembly feature give a possibility to fabricate bulk ceramics orderly assembled using hematite nano cubes.

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