Naturally Self-Assembled Nanosystems and Their Templated Structures for Photonic Applications

Self-assembly has the advantage of fabricating structures of complex functionalities, from molecular levels to as big as macroscopic levels. Natural self-assembly involves self-aggregation of one or more materials (organic and/or inorganic) into desired structures while templated self-assembly involves interstitial space filling of diverse nature entities into self-assembled ordered/disordered templates (both from molecular to macro levels). These artificial and engineered new-generation materials offer many advantages over their individual counterparts. This paper reviews and explores the advantages of such naturally self-assembled hybrid molecular level systems and template-assisted macro-/microstructures targeting simple and low-cost device-oriented fabrication techniques, structural flexibility, and a wide range of photonic applications.

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Self-assembly of a nano hydrogel colloidal array for the sensing of humidity

RSC Advances ◽

10.1039/c7ra12661a ◽

2018 ◽

Vol 8 (18) ◽

pp. 9963-9969 ◽

Cited By ~ 6

Author(s):

Zhe Wang ◽

Min Xue ◽

Herong Zhang ◽

Zihui Meng ◽

Kenneth J. Shea ◽

...

Keyword(s):

Self Assembly ◽

Humidity Sensor ◽

Low Cost ◽

Three Dimensional ◽

Humidity Sensing ◽

Self Assembled

A simple and low-cost humidity sensor based on self-assembled three dimensional nanohydrogel colloidal array was prepared for humidity sensing.

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Co-assembly of helical β3-peptides: a self-assembled analogue of a statistical copolymer

Pure and Applied Chemistry ◽

10.1515/pac-2017-0709 ◽

2017 ◽

Vol 89 (12) ◽

pp. 1809-1816 ◽

Cited By ~ 2

Author(s):

Claire Buchanan ◽

Christopher J. Garvey ◽

Patrick Perlmutter ◽

Adam Mechler

Keyword(s):

Amino Acids ◽

Physical Properties ◽

Self Assembly ◽

Unnatural Amino Acids ◽

The Self ◽

Microscopy Imaging ◽

Wide Range ◽

Self Assembled ◽

Unnatural Peptides ◽

Natural Amino Acids

AbstractUnnatural peptide self-assembly offers the means to design hierarchical nanostructures of controlled geometries, chemical function and physical properties. N-acyl β3 peptides, where all residues are unnatural amino acids, are able to form helical fibrous structures by a head-to-tail assembly of helical monomers, extending the helix via a three point supramolecular hydrogen bonding motif. These helical nanorods were shown to be stable under a wide range of physical conditions, offering a self-assembled analogue of polymeric fibres. Hitherto the self-assembly has only been demonstrated between identical monomers; however the self-assembly motif is sequence-independent, offering the possibility of hetero-assembly of different peptide monomers. Here we present a proof of principle study of head-to-tail co-assembly of two different helical unnatural peptides Ac-β3[WELWEL] and Ac-β3[LIA], where the letters denote the β3 analogues of natural amino acids. By atomic force microscopy imaging it was demonstrated that the homo-assembly and co-assembly of these peptides yield characteristically different structures. Synchrotron small angle X-ray scattering experiments have confirmed the presence of the fibres in the solution and the averaged diameters from modelled data correlate well to the results of AFM imaging. Hence, there is evidence of co-assembly of the fibrous superstructures; given that different monomers may be used to introduce variations into chemical and physical properties, the results demonstrate a self-assembled analogue of a statistical co-polymer that can be used in designing complex functional nanomaterials.

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Molecular engineering of Surfaces Using Self-Assembled Monolayers

Science Progress ◽

10.3184/003685005783238462 ◽

2005 ◽

Vol 88 (1) ◽

pp. 17-48 ◽

Cited By ~ 71

Author(s):

George M. Whitesides ◽

Jennah K. Kriebel ◽

J. Christopher Love

Keyword(s):

Surface Science ◽

Self Assembly ◽

Mammalian Cells ◽

Molecular Level ◽

Level Structure ◽

Molecular Engineering ◽

Gold Silver ◽

Wide Range ◽

Macroscopic Properties ◽

High Level

The self-assembly of molecules into structurally organized monolayers (SAMs) uses the flexibility of organic chemistry and coordination chemistry to generate well-defined, synthetic surfaces with known molecular and macroscopic properties. The process of designing monolayers with a specified structure gives a high level of control over the molecular-level composition in the direction perpendicular to a surface; soft lithographic technique gives useful (if lower) resolution in the plane of the surface. Alkanethiolates adsorbed on gold, silver, mercury, palladium and platinum are currently the best-defined systems of SAMs. They provide substrates for a number of applications-from studies of wetting and electron transport to patterns for growing mammalian cells. SAMs have made organic surfaces a central part of surface science. Understanding the principles by which they form, and connecting molecular-level structure with macroscopic properties, opens a wide range of areas to study and exploitation.

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Hybrid Inorganic/Organic Self-Assembled Clays Nanocomposites for Roll to Roll Fabrication in Photovoltaics

MRS Proceedings ◽

10.1557/proc-1196-c06-22 ◽

2009 ◽

Vol 1196 ◽

Author(s):

Peter Njagwa Kariuki ◽

Jessica Gendron ◽

Christopher Matthew Madl ◽

Jasper Chiguma ◽

Michael E Hagerman ◽

...

Keyword(s):

Titanium Dioxide ◽

Indium Tin Oxide ◽

Self Assembly ◽

Titanium Dioxide Nanoparticles ◽

Low Cost ◽

Flexible Substrate ◽

Roll To Roll ◽

Organic Photovoltaic Materials ◽

Self Assembled ◽

Electrically Conducting Polymers

AbstractWe have been developing a new approach to layered hybrid (inorganic/organic) photovoltaic materials for fabrication by Roll-to-Roll (R2R) manufacturing. In this report, we combine the low cost and processability of organic electrically conducting polymers with the efficiency of dye sensitized titanium dioxide, semi-conductor quantum dots (CdSe) self-assembled on layered clay materials (Laponite) onto indium tin oxide coated flexible substrate polyethylene terephthalate (PET) substrates. We have shown electron transfer, guest-guest and host-guest interactions, charge separation, spectral line broadening, and quenching of fluorescence signals which indicate electronic coupling of the dye [Ru(bpy)3]2+ on a CdSe nanocrystal and titanium dioxide nanoparticles. Scanning electron microscopy and atomic force microscopy demonstrate successful nanoparticle formation and thin film self-assembly, as well as surface morphology and polymer thickness.

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Design of functionalised circular tandem repeat proteins with longer repeat topologies and enhanced subunit contact surfaces

Communications Biology ◽

10.1038/s42003-021-02766-y ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Jazmine P. Hallinan ◽

Lindsey A. Doyle ◽

Betty W. Shen ◽

Mesfin M. Gewe ◽

Brittany Takushi ◽

...

Keyword(s):

Tandem Repeat ◽

Self Assembly ◽

De Novo ◽

Viral Receptor ◽

Viral Neutralization ◽

Sh2 Domains ◽

Repeat Proteins ◽

Wide Range ◽

Tandem Repeat Proteins ◽

New Generation

AbstractCircular tandem repeat proteins (‘cTRPs’) are de novo designed protein scaffolds (in this and prior studies, based on antiparallel two-helix bundles) that contain repeated protein sequences and structural motifs and form closed circular structures. They can display significant stability and solubility, a wide range of sizes, and are useful as protein display particles for biotechnology applications. However, cTRPs also demonstrate inefficient self-assembly from smaller subunits. In this study, we describe a new generation of cTRPs, with longer repeats and increased interaction surfaces, which enhanced the self-assembly of two significantly different sizes of homotrimeric constructs. Finally, we demonstrated functionalization of these constructs with (1) a hexameric array of peptide-binding SH2 domains, and (2) a trimeric array of anti-SARS CoV-2 VHH domains. The latter proved capable of sub-nanomolar binding affinities towards the viral receptor binding domain and potent viral neutralization function.

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Peptide Nanomaterials for Drug Delivery Applications

Current Protein and Peptide Science ◽

10.2174/1389203721666200101091834 ◽

2020 ◽

Vol 21 (4) ◽

pp. 401-412 ◽

Cited By ~ 1

Author(s):

Sreekanth Pentlavalli ◽

Sophie Coulter ◽

Garry Laverty

Keyword(s):

Drug Delivery ◽

Self Assembly ◽

Diverse Range ◽

Drug Molecules ◽

Sustained Drug Delivery ◽

Self Assembling ◽

Wide Range ◽

Methods Of Synthesis ◽

Self Assembled

Self-assembled peptides have been shown to form well-defined nanostructures which display outstanding characteristics for many biomedical applications and especially in controlled drug delivery. Such biomaterials are becoming increasingly popular due to routine, standardized methods of synthesis, high biocompatibility, biodegradability and ease of upscale. Moreover, one can modify the structure at the molecular level to form various nanostructures with a wide range of applications in the field of medicine. Through environmental modifications such as changes in pH and ionic strength and the introduction of enzymes or light, it is possible to trigger self-assembly and design a host of different self-assembled nanostructures. The resulting nanostructures include nanotubes, nanofibers, hydrogels and nanovesicles which all display a diverse range of physico-chemical and mechanical properties. Depending on their design, peptide self-assembling nanostructures can be manufactured with improved biocompatibility and in vivo stability and the ability to encapsulate drugs with the capacity for sustained drug delivery. These molecules can act as carriers for drug molecules to ferry cargo intracellularly and respond to stimuli changes for both hydrophilic and hydrophobic drugs. This review explores the types of self-assembling nanostructures, the effects of external stimuli on and the mechanisms behind the assembly process, and applications for such technology in drug delivery.

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Formation of Ordered Silica–Organic Hybrids by Self-Assembly of Hydrolyzed Organoalkoxysilanes with Long Organic Chains

MRS Proceedings ◽

10.1557/proc-707-v2.8.1 ◽

2001 ◽

Vol 707 ◽

Author(s):

Kazuyuki Kuroda ◽

Atsushi Shimojima

Keyword(s):

Self Assembly ◽

Spin Coating ◽

Molecular Level ◽

Precursor Solution ◽

Materials Chemistry ◽

Hybrid Films ◽

Structural Units ◽

New Class ◽

Wide Range ◽

Oriented Films

ABSTRACTVarious layered hybrid films prepared from organoalkoxysilanes with long organic chains, based on the self-assembly of the hydrolyzed species, are reviewed. Morphological control of transparent and oriented films was achieved by cohydrolysis and polycondensation with tetraalkoxysilanes, followed by dip- or spin-coating. In addition to alkyltrialkoxysilanes, alkyldimethylmonoalkoxy- and alkylmethyldialkoxy-silanes were also used as the structural units, implying that the inorganic–organic interface can be designed at a molecular level. In these cases, co-condensation in the precursor solution plays an essential role in the formation of homogeneous and ordered films. Alkenyltriethoxysilanes with terminal C=C bonds were also employed to prepare layered hybrid films. Interlayer chains were polymerized upon UV irradiation, and the resulting films exhibited a significant increase in the hardness if compared with the films before polymerization. Hybrid films thus obtained are a new class of materials and of great interest for a wide range of materials chemistry.

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Self-assembly of Functional Nanostructures by Short Helical Peptide Building Blocks

Protein and Peptide Letters ◽

10.2174/0929866525666180917163142 ◽

2019 ◽

Vol 26 (2) ◽

pp. 88-97 ◽

Cited By ~ 8

Author(s):

Santu Bera ◽

Ehud Gazit

Keyword(s):

Self Assembly ◽

Amyloid Fibrils ◽

Building Blocks ◽

Smart Devices ◽

Helical Peptides ◽

Functional Roles ◽

Mesoscale Structures ◽

Self Assembling ◽

Wide Range ◽

Self Assembled

The self-assembly of short peptide building blocks into well-ordered nanostructures is a key direction in bionanotechnology. The formation of β -sheet organizations by short peptides is well explored, leading to the development of a wide range of functional assemblies. Likewise, many natural proteinaceous materials, such as silk and amyloid fibrils, are based on β-sheet structures. In contrast, collagen, the most abundant protein in mammals, is based on helical arrangement. Similar to β-sheet structures, short helical peptides have been recently discovered to possess a diverse set of functionalities with the potential to fabricate artificial self-assembling materials. Here, we outline the functional roles of self-assembled nanostructures formed by short helical peptides and their potential as artificial materials. We focus on the association between self-assembled mesoscale structures and their material function and demonstrate the way by which this class of building blocks bears the potential for diverse applications, such as the future fabrication of smart devices.

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Towards Safer Primers: A Review

Technologies ◽

10.3390/technologies7040075 ◽

2019 ◽

Vol 7 (4) ◽

pp. 75

Author(s):

Stefan Lundgaard ◽

Soon Ng ◽

Damien Cahill ◽

Johan Dahlberg ◽

Dong Ruan ◽

...

Keyword(s):

Heavy Metal ◽

Metal Oxide ◽

Low Cost ◽

Health And Safety ◽

Control Mechanisms ◽

Wide Range ◽

New Generation ◽

Secondary Explosive

Primers are used to reliably initiate a secondary explosive in a wide range of industrial and defence applications. However, established primer technologies pose both direct and indirect risks to health and safety. This review analyses a new generation of primer materials and ignition control mechanisms that have been developed to address these risks in firearms. Electrically or optically initiated metal, oxide and semiconductor-based devices show promise as alternatives for heavy metal percussive primers. The prospects for wider use of low-cost, safe, reliable and non-toxic primers are discussed in view of these developments.

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Stretchable and Hydrophobic Electrochromic Devices Using Wrinkled Graphene and PEDOT:PSS

Journal of Nanomaterials ◽

10.1155/2018/3230293 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Srinivasa Kartik Nemani ◽

Dayong Chen ◽

Marwan H. Mohamed ◽

Hossein Sojoudi

Keyword(s):

Self Assembly ◽

Graphene Film ◽

Electrochromic Device ◽

Color Contrast ◽

Water Contact ◽

Smart Windows ◽

Wide Range ◽

Average Water ◽

Materials Used ◽

New Generation

We present an electrochromic device (ECD) fabricated using PEDOT:PSS and graphene as active conductive electrode films and a flexible compliant polyurethane substrate with 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TSFI) additive, as ionic medium. This device with a docile, elastic intermediate substrate along with a transparency controlled PEDOT:PSS film provides a wide color contrast and fast switching rate. We harness wrinkling instability of graphene to achieve a hydrophobic nature without compromising transparency of the ECD. This mechanical self-assembly approach helps in controlling the wavelength of wrinkles generated by inducing measured prestrain conditions and regulating the modulus contrast by selection of underlying materials used, hereby controlling the extent of transparency. The reduction and oxidation switching times for the device were analyzed to be 5.76 s and 5.34 s for a 90% transmittance change at an operating DC voltage of 15 ± 0.1 V. Strain dependent studies show that the performance was robust with the device retaining switching contrasts even at 15% uniaxial strain conditions. Our device also exhibits superior antiwetting properties with an average water contact angle of 110° ± 2° at an induced radial prestrain of 30% in the graphene film. A wide range color contrast, flexibility, and antiwetting nature of the device envision its uses in smart windows, visors, and other wearable equipment where these functionalities are of outmost importance for developing new generation of smart interactive devices.

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