Artificial spider silk from ion-doped and twisted core-sheath hydrogel fibres

AbstractSpider silks show unique combinations of strength, toughness, extensibility, and energy absorption. To date, it has been difficult to obtain spider silk-like mechanical properties using non-protein approaches. Here, we report on an artificial spider silk produced by the water-evaporation-induced self-assembly of hydrogel fibre made from polyacrylic acid and silica nanoparticles. The artificial spider silk consists of hierarchical core-sheath structured hydrogel fibres, which are reinforced by ion doping and twist insertion. The fibre exhibits a tensile strength of 895 MPa and a stretchability of 44.3%, achieving mechanical properties comparable to spider silk. The material also presents a high toughness of 370 MJ m−3 and a damping capacity of 95%. The hydrogel fibre shows only ~1/9 of the impact force of cotton yarn with negligible rebound when used for impact reduction applications. This work opens an avenue towards the fabrication of artificial spider silk with applications in kinetic energy buffering and shock-absorbing.

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Effect of boron incorporation on the bioactivity, structure, and mechanical properties of ordered mesoporous bioactive glasses

Journal of Materials Chemistry B ◽

10.1039/c9tb01805k ◽

2020 ◽

Vol 8 (7) ◽

pp. 1456-1465 ◽

Cited By ~ 8

Author(s):

Leonie Deilmann ◽

Oliver Winter ◽

Bianca Cerrutti ◽

Henrik Bradtmüller ◽

Christopher Herzig ◽

...

Keyword(s):

Mechanical Properties ◽

Self Assembly ◽

Sol Gel ◽

Bioactive Glasses ◽

Structure Directing Agent ◽

Structural Investigations ◽

Ordered Mesoporous ◽

Evaporation Induced Self Assembly

B2O3 doped (0.5–15 mol%) ordered mesoporous bioactive glasses were synthesized via sol–gel based evaporation-induced self-assembly using P123 as a structure directing agent and characterized by biokinetic, mechanical and structural investigations.

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Post-secretion processing influences spider silk performance

Journal of The Royal Society Interface ◽

10.1098/rsif.2012.0277 ◽

2012 ◽

Vol 9 (75) ◽

pp. 2479-2487 ◽

Cited By ~ 23

Author(s):

Sean J. Blamires ◽

Chung-Lin Wu ◽

Todd A. Blackledge ◽

I-Min Tso

Keyword(s):

Mechanical Properties ◽

Amino Acid ◽

Ground State ◽

Spider Silk ◽

Mechanical Performance ◽

Protein Composition ◽

Compositional Changes ◽

Spinning Speed ◽

Spider Silks ◽

Β Sheet

Phenotypic variation facilitates adaptations to novel environments. Silk is an example of a highly variable biomaterial. The two-spidroin (MaSp) model suggests that spider major ampullate (MA) silk is composed of two proteins—MaSp1 predominately contains alanine and glycine and forms strength enhancing β-sheet crystals, while MaSp2 contains proline and forms elastic spirals. Nonetheless, mechanical properties can vary in spider silks without congruent amino acid compositional changes. We predicted that post-secretion processing causes variation in the mechanical performance of wild MA silk independent of protein composition or spinning speed across 10 species of spider. We used supercontraction to remove post-secretion effects and compared the mechanics of silk in this ‘ground state’ with wild native silks. Native silk mechanics varied less among species compared with ‘ground state’ silks. Variability in the mechanics of ‘ground state’ silks was associated with proline composition. However, variability in native silks did not. We attribute interspecific similarities in the mechanical properties of native silks, regardless of amino acid compositions, to glandular processes altering molecular alignment of the proteins prior to extrusion. Such post-secretion processing may enable MA silk to maintain functionality across environments, facilitating its function as a component of an insect-catching web.

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Synergistically enhanced thermoelectric performance by optimizing the composite ratio between hydrothermal Sb2Se3 and self-assembled β-Cu2Se nanowires

CrystEngComm ◽

10.1039/d1ce00149c ◽

2021 ◽

Author(s):

Minsu Kim ◽

Dabin Park ◽

Jooheon Kim

Keyword(s):

Self Assembly ◽

Hydrothermal Reaction ◽

Thermoelectric Performance ◽

Water Evaporation ◽

Assembly Method ◽

Evaporation Induced Self Assembly ◽

Self Assembled

Sb2Se3 and β-Cu2Se nanowires were synthesized via hydrothermal reaction and a water-evaporation induced self-assembly method, respectively, and a 70%-Sb2Se3 and 30%-β-Cu2Se disk pellet shows enhanced thermoelectric performance.

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Effect of material flexibility on the thermodynamics and kinetics of hydrophobically induced evaporation of water

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1620335114 ◽

2017 ◽

Vol 114 (13) ◽

pp. E2548-E2555 ◽

Cited By ~ 29

Author(s):

Y. Elia Altabet ◽

Amir Haji-Akbari ◽

Pablo G. Debenedetti

Keyword(s):

Mechanical Properties ◽

Free Energy ◽

Self Assembly ◽

Substrate Material ◽

Free Energy Calculations ◽

General Mechanism ◽

Water Evaporation ◽

Theoretical Predictions ◽

Basic Physics ◽

Order Of Magnitude

The evaporation of water induced by confinement between hydrophobic surfaces has received much attention due to its suggested functional role in numerous biophysical phenomena and its importance as a general mechanism of hydrophobic self-assembly. Although much progress has been made in understanding the basic physics of hydrophobically induced evaporation, a comprehensive understanding of the substrate material features (e.g., geometry, chemistry, and mechanical properties) that promote or inhibit such transitions remains lacking. In particular, comparatively little research has explored the relationship between water’s phase behavior in hydrophobic confinement and the mechanical properties of the confining material. Here, we report the results of extensive molecular simulations characterizing the rates, free energy barriers, and mechanism of water evaporation when confined between model hydrophobic materials with tunable flexibility. A single-order-of-magnitude reduction in the material’s modulus results in up to a nine-orders-of-magnitude increase in the evaporation rate, with the corresponding characteristic time decreasing from tens of seconds to tens of nanoseconds. Such a modulus reduction results in a 24-orders-of-magnitude decrease in the reverse rate of condensation, with time scales increasing from nanoseconds to tens of millions of years. Free energy calculations provide the barriers to evaporation and confirm our previous theoretical predictions that making the material more flexible stabilizes the confined vapor with respect to liquid. The mechanism of evaporation involves surface bubbles growing/coalescing to form a subcritical gap-spanning tube, which then must grow to cross the barrier.

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Transparent Montmorillonite/cellulose Nanofibril Nanocomposite Films: the Influence of Exfoliation Degree and Interfacial Interaction

10.21203/rs.3.rs-1210316/v1 ◽

2022 ◽

Author(s):

Chuan Sun ◽

Guanhui Li ◽

Jingyu Wang ◽

Zhiqiang Fang ◽

Famei Qin ◽

...

Keyword(s):

Self Assembly ◽

Nanocomposite Film ◽

High Performance ◽

Transmission Rate ◽

Cellulose Nanofibrils ◽

Nanocomposite Films ◽

Light Transmittance ◽

Water Evaporation ◽

Interfacial Interactions ◽

Evaporation Induced Self Assembly

Abstract To obtain high performance of nanocomposite films made of cellulose nanofibrils (CNFs) and montmorillonites (MMTs), highly ordered nanostructures and abundant interfacial interactions are of extreme importance, especially for CNF film with high MMT content. Here, we tend to unveil the influence of exfoliation degree of MMTs and their interfacial interactions with CNFs on the properties of ensuing nanocomposite films. Monolayer MMTs prefer to form highly ordered nanostructure during water evaporation induced self-assembly. The obtained nanocomposite film with 30 wt% monolayer MMTs exhibits a tensile strength of 132 MPa, a total light transmittance of 90.2% (550nm), and water vapor transmission rate (WVTR) of 41.5 g•mm/m2•day, better than the film made of original bulk MMTs and CNFs (30 MPa strength, 60% transparency, and 78.7 g•mm/m2•day WVTR). Moreover, the physical properties (153 MPa strength and 20.9 g•mm/m2•day WVTR) of nanocomposite film can be further enhanced by constructing ionic interactions between the monolayer MMT and CNF using 0.5 wt% cationic polyethylenimine (PEI). However, as the amount of PEI continues to increase, its performance will be deteriorated dramatically because of the disordered orientation of monolayer MMTs. This work could provide an insight into the fabrication of high performance MMT/CNF nanocomposite film for advanced applications.

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Critical role of minor eggcase silk component in promoting spidroin chain alignment and strong fiber formation

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2100496118 ◽

2021 ◽

Vol 118 (38) ◽

pp. e2100496118

Author(s):

Tiantian Fan ◽

Ruiqi Qin ◽

Yan Zhang ◽

Jingxia Wang ◽

Jing-Song Fan ◽

...

Keyword(s):

Self Assembly ◽

Spider Silk ◽

Critical Role ◽

Minor Component ◽

Fiber Formation ◽

Repetitive Domain ◽

Chain Alignment ◽

Main Components ◽

Spider Silks

Natural spider silk with extraordinary mechanical properties is typically spun from more than one type of spidroin. Although the main components of various spider silks have been widely studied, little is known about the molecular role of the minor silk components in spidroin self-assembly and fiber formation. Here, we show that the minor component of spider eggcase silk, TuSp2, not only accelerates self-assembly but remarkably promotes molecular chain alignment of spidroins upon physical shearing. NMR structure of the repetitive domain of TuSp2 reveals that its dimeric structure with unique charged surface serves as a platform to recruit different domains of the main eggcase component TuSp1. Artificial fiber spun from the complex between TuSp1 and TuSp2 minispidroins exhibits considerably higher strength and Young’s modulus than its native counterpart. These results create a framework for rationally designing silk biomaterials based on distinct roles of silk components.

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