Self-Assembly of Temperature Sensitive Unilamellar Vesicles by a Blend of Block Copolymers in Aqueous Solution

A self-assembled unilamellar vesicle, which can be used as a drug delivery system, was easily and simply fabricated using a blended system of Pluronic block copolymers. Controlling the hydrophilic mass fraction of block copolymers (by blending the block copolymer with a different hydrophilic mass fraction) and temperature (i.e., the hydrophobic interaction is controlled), a vesicular structure was formed. Small angle neutron scattering measurements showed that the vesicular structure had diameters of empty cores from 13.6 nm to 79.6 nm, and thicknesses of the bilayers from 2.2 nm to 8.7 nm when the hydrophobic interaction was changed. Therefore, considering that the temperature of the vesicle formation is controllable by the concentration of the blended block copolymers, it is possible for them to be applied in a wide range of potential applications, for example, as nanoreactors and nanovehicles.

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A Structurally Variable Hinged Tetrahedron Framework from DNA Origami

Journal of Nucleic Acids ◽

10.4061/2011/360954 ◽

2011 ◽

Vol 2011 ◽

pp. 1-9 ◽

Cited By ~ 18

Author(s):

David M. Smith ◽

Verena Schüller ◽

Carsten Forthmann ◽

Robert Schreiber ◽

Philip Tinnefeld ◽

...

Keyword(s):

Self Assembly ◽

Gel Electrophoresis ◽

Imaging Techniques ◽

Building Blocks ◽

Dna Origami ◽

Microscopy Technique ◽

Wire Frame ◽

Wide Range ◽

Potential Applications ◽

Linker Molecules

Nanometer-sized polyhedral wire-frame objects hold a wide range of potential applications both as structural scaffolds as well as a basis for synthetic nanocontainers. The utilization of DNA as basic building blocks for such structures allows the exploitation of bottom-up self-assembly in order to achieve molecular programmability through the pairing of complementary bases. In this work, we report on a hollow but rigid tetrahedron framework of 75 nm strut length constructed with the DNA origami method. Flexible hinges at each of their four joints provide a means for structural variability of the object. Through the opening of gaps along the struts, four variants can be created as confirmed by both gel electrophoresis and direct imaging techniques. The intrinsic site addressability provided by this technique allows the unique targeted attachment of dye and/or linker molecules at any point on the structure's surface, which we prove through the superresolution fluorescence microscopy technique DNA PAINT.

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Solvent Effects on the Synthesis of Polymeric Nanoparticles via Block Copolymer Self-Assembly Using Microporous Membranes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1000.324 ◽

2020 ◽

Vol 1000 ◽

pp. 324-330

Author(s):

Sri Agustina ◽

Masayoshi Tokuda ◽

Hideto Minami ◽

Cyrille Boyer ◽

Per B. Zetterlund

Keyword(s):

Block Copolymer ◽

Block Copolymers ◽

Self Assembly ◽

Polymeric Nanoparticles ◽

Raft Polymerization ◽

Membrane Emulsification ◽

Membrane Pore ◽

Novel Technique ◽

Wide Range ◽

Membrane Pore Size

The self-assembly of block copolymers has attracted attention for many decades because it can yield polymeric nanoobjects with a wide range of morphologies. Membrane emulsification is a fairly novel technique for preparation of various types of emulsions, which relies on the dispersed phase passing through a membrane in order to effect droplet formation. In this study, we have prepared polymeric nanoparticles of different morphologies using self-assembly of asymmetric block copolymers in connection with membrane emulsification. Shirasu Porous Glass (SPG) membranes has been employed as the membrane emulsification equipment, and poly (oligoethylene glycol acrylate)-block-poly (styrene) (POEGA-b-PSt) copolymers prepared via RAFT polymerization. It has been found that a number of different morphologies can be achieved using this novel technique, including spheres, rods, and vesicles. Interestingly, the results have shown that the morphology can be controlled not only by adjusting experimental parameters specific to the membrane emulsification step such as membrane pore size and pressure, but also by changing the nature of organic solvent. As such, this method provides a novel route to these interesting nanoobjects, with interesting prospects in terms of exercising morphology control without altering the nature of the block copolymer itself.

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In situ and real-time small-angle neutron scattering studies of living anionic polymerization process and polymerization-induced self-assembly of block copolymers

Physica B Condensed Matter ◽

10.1016/j.physb.2006.06.049 ◽

2006 ◽

Vol 385-386 ◽

pp. 742-744 ◽

Cited By ~ 9

Author(s):

H. Tanaka ◽

K. Yamauchi ◽

H. Hasegawa ◽

N. Miyamoto ◽

S. Koizumi ◽

...

Keyword(s):

Block Copolymers ◽

Neutron Scattering ◽

Real Time ◽

Small Angle ◽

Anionic Polymerization ◽

Self Assembly ◽

Small Angle Neutron Scattering ◽

Polymerization Process ◽

Living Anionic Polymerization

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HYBRID SEMICONDUCTING QUANTUM DOTS–METALLIC NANOPARTICLES ARRAYS FOR POSSIBLE NANOPHOTONIC DEVICES

International Journal of Nanoscience ◽

10.1142/s0219581x11009519 ◽

2011 ◽

Vol 10 (04n05) ◽

pp. 1113-1118

Author(s):

M. HARIDAS ◽

J. K. BASU

Keyword(s):

Quantum Dots ◽

Self Assembly ◽

Metallic Nanoparticles ◽

Quantum Information Processing ◽

Imaging Techniques ◽

Large Area ◽

Nanophotonic Devices ◽

Wide Range ◽

Potential Applications ◽

Assembly Technique

Arrays of quantum dots and hybrid arrays of semiconducting quantum dots and metallic nanoparticles have wide range of potential applications from nanophotonics to quantum information processing. Creating such arrays with well-defined morphology and order over a large area is a challenge. We present a reliable method for constructing such arrays using simple self assembly technique. The reliability of the method is verified using AFM. The emission properties of such system are studied using high resolution imaging techniques and we have given the possible explanation for the observed phenomena.

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Morphology of crystalline–amorphous olefin block copolymers in solution characterized by small-angle neutron scattering and microscopy

Journal of Applied Crystallography ◽

10.1107/s1600576715019226 ◽

2015 ◽

Vol 48 (6) ◽

pp. 1860-1869 ◽

Cited By ~ 6

Author(s):

Aurel Radulescu ◽

Günter Goerigk ◽

Lewis Fetters ◽

Dieter Richter

Keyword(s):

Block Copolymers ◽

Neutron Scattering ◽

Small Angle ◽

Self Assembly ◽

Small Angle Neutron Scattering ◽

Chain Structure ◽

Hierarchical Organization ◽

Single Chain ◽

Scanning Calorimetry ◽

Assembly Behavior

The single-chain properties and self-assembly behavior in dilute solution of olefin block copolymers obtained by chain-shuttling technology and consisting of alternating crystallizable and amorphous ethylene/1-octene blocks were investigated by pinhole and focusing small-angle neutron scattering techniques, optical microscopy in bright-field and crossed-polarizer modes, and differential scanning calorimetry. The complex hydrocarbon soluble (precipitant free) macro-aggregates formed with decreasing temperature are characterized by spherulitic textures. The spherulites yield, on one hand, a morphology that depends on the chain structure properties and, on the other hand, multiple structural levels with a hierarchical organization that ranges from 10 Å up to tens of micrometres. This morphology displays peculiarities dictated by the polydisperse character of these materials.

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α-Cyclodextrin-Based Polypseudorotaxane Hydrogels

Materials ◽

10.3390/ma13010133 ◽

2019 ◽

Vol 13 (1) ◽

pp. 133 ◽

Cited By ~ 2

Author(s):

Adrian Domiński ◽

Tomasz Konieczny ◽

Piotr Kurcok

Keyword(s):

Self Assembly ◽

Polymeric Nanoparticles ◽

Functional Materials ◽

Building Blocks ◽

Polymer Chains ◽

Physical Interaction ◽

Wide Range ◽

Potential Applications ◽

Noncovalent Bonds ◽

Significant Attention

Supramolecular hydrogels that are based on inclusion complexes between α-cyclodextrin and (co)polymers have gained significant attention over the last decade. They are formed via dynamic noncovalent bonds, such as host–guest interactions and hydrogen bonds, between various building blocks. In contrast to typical chemical crosslinking (covalent linkages), supramolecular crosslinking is a type of physical interaction that is characterized by great flexibility and it can be used with ease to create a variety of “smart” hydrogels. Supramolecular hydrogels based on the self-assembly of polypseudorotaxanes formed by a polymer chain “guest” and α-cyclodextrin “host” are promising materials for a wide range of applications. α-cyclodextrin-based polypseudorotaxane hydrogels are an attractive platform for engineering novel functional materials due to their excellent biocompatibility, thixotropic nature, and reversible and stimuli-responsiveness properties. The aim of this review is to provide an overview of the current progress in the chemistry and methods of designing and creating α-cyclodextrin-based supramolecular polypseudorotaxane hydrogels. In the described systems, the guests are (co)polymer chains with various architectures or polymeric nanoparticles. The potential applications of such supramolecular hydrogels are also described.

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