Viscoelastic solids explain spider web stickiness

Sahni, Vasav; Blackledge, Todd A.; Dhinojwala, Ali

doi:10.1038/ncomms1019

Cited by 155 publications

(214 citation statements)

References 7 publications

Supporting

Mentioning

205

Contrasting

Unclassified

Order By: Relevance

“…ivy nanoparticle | ivy adhesive | arabinogalactan protein | adhesion mechanism | reconstructed adhesive A lthough there is a growing interest in exploring mechanisms regulating a variety of adhesive behaviors in the animal kingdom (1)(2)(3)(4)(5)(6), the molecular basis allowing creeping plants, such as English ivy (Hedera helix), to generate sufficient adhesive force, aiding in clinging to vertical surfaces, is rarely discussed (Fig. 1A).…”

mentioning

confidence: 99%

Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

Huang

Wang

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Over 130 y have passed since Charles Darwin first discovered that the adventitious roots of English ivy (Hedera helix) exude a yellowish mucilage that promotes the capacity of this plant to climb vertical surfaces. Unfortunately, little progress has been made in elucidating the adhesion mechanisms underlying this high-strength adhesive. In the previous studies, spherical nanoparticles were observed in the viscous exudate. Here we show that these nanoparticles are predominantly composed of arabinogalactan proteins (AGPs), a superfamily of hydroxyproline-rich glycoproteins present in the extracellular spaces of plant cells. The spheroidal shape of the AGP-rich ivy nanoparticles results in a low viscosity of the ivy adhesive, and thus a favorable wetting behavior on the surface of substrates. Meanwhile, calciumdriven electrostatic interactions among carboxyl groups of the AGPs and the pectic acids give rise to the cross-linking of the exuded adhesive substances, favor subsequent curing (hardening) via formation of an adhesive film, and eventually promote the generation of mechanical interlocking between the adventitious roots of English ivy and the surface of substrates. Inspired by these molecular events, a reconstructed ivy-mimetic adhesive composite was developed by integrating purified AGP-rich ivy nanoparticles with pectic polysaccharides and calcium ions. Information gained from the subsequent tensile tests, in turn, substantiated the proposed adhesion mechanisms underlying the ivy-derived adhesive. Given that AGPs and pectic polysaccharides are also observed in bioadhesives exuded by other climbing plants, the adhesion mechanisms revealed by English ivy may forward the progress toward understanding the general principles underlying diverse botanic adhesives.ivy nanoparticle | ivy adhesive | arabinogalactan protein | adhesion mechanism | reconstructed adhesive A lthough there is a growing interest in exploring mechanisms regulating a variety of adhesive behaviors in the animal kingdom (1-6), the molecular basis allowing creeping plants, such as English ivy (Hedera helix), to generate sufficient adhesive force, aiding in clinging to vertical surfaces, is rarely discussed (Fig. 1A). Previous studies have emphasized mechanical strategies exploited by multiple climbing organs that evolve in plants (7-11). Nevertheless, the role of the glue-like viscous exudates that are observed on the majority of these organs and that cement the plants to the substrates has been less explored (10,12,13). Diverse polysaccharides and glycoproteins, comprising mucilaginous pectins, arabinogalactans, arabinogalactan proteins (AGPs), and many others, have been identified to be the predominant components in these adhesive substances (14-17); however, the molecular mechanisms underlying the high-strength adhesion remain elusive.By means of atomic force microscopy (AFM), bulk spherical organic nanoparticles have been observed in the exudates derived from the root hairs of English ivy (18-20). These proteinaceous nanoparticles are presum...

show abstract

mentioning

confidence: 99%

Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

Huang

Wang

et al. 2016

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…Natural spider silk has superior mechanical properties, particularly its high specific strength (approximately 5 times greater than steel) and excellent flexibility (approximately 10 times greater than aramid) and toughness (the highest of any material) [76][77][78]. …”

Section: Other Animalsmentioning

confidence: 99%

Recent biomedical applications of bio-sourced materials

Elbaz

Gao

et al. 2018

Bio-des. Manuf.

View full text Add to dashboard Cite

Natural anisotropic nanostructures occurring in several organisms have gained more and more attention because of their obvious advantages in sensitivity, stability, security, miniaturization, portability, online use, and remote monitoring. Due to the development of research on nature-inspired bionic structures and the demand for highly efficient, low-cost microfabrication techniques, an understanding of and the ability to replicate the mechanism of structural coloration have become increasingly significant. These sophisticated structures have many unique functions and are used in many applications. Many sensors have been proposed based on their novel structures and unique optical properties. Several of these bio-inspired sensors have been used for infrared radiation/thermal, pH, and vapor techniques, among others, and have been discussed in detail, with an intense focus on several biomedical applications. However, many applications have yet to be discovered. In this review, we will describe these nanostructured materials based on their sources in nature and various structures, such as layered, hierarchical, and helical structures. In addition, we discuss the functions endowed by these structures, such as superhydrophobicity, adhesion, and high strength, enabling them to be employed in a number of applications in biomedical fields, including cell cultivation, biosensors, and tissue engineering.

show abstract

“…Viscid capture threads overcome this constraint on adhesion through a highly effective suspension bridge mechanism that is enabled by the high elasticity of both the flagelliform axial fibers and the viscous glue droplets themselves (Opell & Hendricks 2007;Opell et al 2008;Sahni et al 2010). The viscid glue droplets have their own hierarchical structuring and consist of a core of cross-linked fibrous glycoproteins embedded in a liquid matrix (Opell & Hendricks 2010).…”

Section: Orb Websmentioning

confidence: 99%

“…Adhesion occurs mostly due to the interface of these glycoproteins with the surface (Vollrath & Tillinghast 1991). As a viscid thread begins to pull away from a surface, individual glue droplets extend greatly before they detach (Sahni et al 2010;Opell et al 2011). This allows multiple glue droplets to simultaneously resist pull-off, generating significantly more adhesion (Opell & Hendricks 2007).…”

Section: Orb Websmentioning

confidence: 99%

Parasitoid suppression and life-history modifications in a wolf spider following infection by larvae of an acrocerid fly

Toft¹,

Nielsen²,

Funch³

2012

Journal of Arachnology

View full text Add to dashboard Cite

Abstract. Spiders construct a wide variety of silk structures, ranging from draglines to prey capture webs. Spider silks rank among the toughest materials known to science, and these material properties are critical for understanding how silk structures, such as webs, function. However, the mechanics of spider silk are often ignored in the study of webs. This review aims to show how the material properties of silk proteins, the structural properties of silk threads, and the architectures of webs ultimately interact to determine the function of orb webs during prey capture. I first provide a brief introduction into spider silk and how to characterize its material and structural properties. I then examine the function of draglines as ''lifelines'' to provide a well-understood example of the interaction of material and structural properties in silk function. Next, I examine how orb webs function in prey capture by first intercepting insects, then stopping their kinetic energy of flight, and finally retaining the insects long enough to be subdued by spiders. I show how variation in the material and structural properties of silk acts synergistically to facilitate the stopping and retention potentials of orb webs, and why this can occur in opposition to how orb webs intercept prey. Finally, I summarize why information on the material properties and structures of silk threads needs to be better incorporated into future investigations of spider webs in general.

show abstract

Viscoelastic solids explain spider web stickiness

Cited by 155 publications

References 7 publications

Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

Nanospherical arabinogalactan proteins are a key component of the high-strength adhesive secreted by English ivy

Recent biomedical applications of bio-sourced materials

Parasitoid suppression and life-history modifications in a wolf spider following infection by larvae of an acrocerid fly

Contact Info

Product

Resources

About