Biomimetics on the micro- and nanoscale – The 25th anniversary of the lotus effect

• Matthias Mail,
• Kerstin Koch,
• Thomas Speck,
• William M. Megill and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2023, 14, 850–856, doi:10.3762/bjnano.14.69

• and insect attachment on leaf surfaces of Schismatoglottis calyptrata (Araceae)” a study of the development of cuticular ridges on the adaxial leaf surfaces during leaf ontogeny of the tropical Araceae S. calyptrata. The structure of these microscopic ridges helps plants to defend themselves against

• pest insects by reducing the frictional forces experienced when they walk on the leaves. This structure might also provide mechanical stability to the growing plant organs and has an impact on the wettability of the leaves. Using polymer replicas of adaxial leaf surfaces at various scales, the surface

• densely covers both leaf surfaces, contributes to the plant's adaptation to severe environmental conditions in Antarctica by increasing its resistance to cold temperatures, icing, harmful UV radiation, and dehydration. In the paper “Micro-structures, nanomechanical properties and flight performance of

Straight roads into nowhere – obvious and not-so-obvious biological models for ferrophobic surfaces

• Wilfried Konrad,
• Christoph Neinhuis and
• Anita Roth-Nebelsick

Beilstein J. Nanotechnol. 2022, 13, 1345–1360, doi:10.3762/bjnano.13.111

• “staying dry under water” for a much longer time [4][5]. Such surfaces usually feature functional structures that are larger than the wax crystals on the Lotus leaf (or other superhydrophobic leaf surfaces showing specially structured wax covers). Many of these surfaces possess hairs, such as those of the

Design of a biomimetic, small-scale artificial leaf surface for the study of environmental interactions

• Miriam Anna Huth,
• Axel Huth,
• Lukas Schreiber and
• Kerstin Koch

Beilstein J. Nanotechnol. 2022, 13, 944–957, doi:10.3762/bjnano.13.83

• (e.g., applied surfactants) interactions on natural leaf surfaces, the chemical composition and the wetting behavior should be the same in both. Therefore, the morphology, chemistry, and wetting properties of natural and artificial surfaces with recrystallized wax structures were analyzed by scanning

• the biological model. The artificial surfaces imitating the leaves should have the same chemical and wetting properties as leaf surfaces. To prove these criteria, the chemical composition of the native and transferred wax extracts, the morphology of native and recrystallized wax crystals and the

• according to their positions on the plant. Development of artificial leaf surfaces Wax for recrystallization was extracted from wheat leaves of outdoor plants by immersing the leaves in chloroform (99.9% HPLC grade, Carl Roth GmbH und Co. KG, Karlsruhe, Germany) for 20 s. The extracts were then filtered

Hierachical epicuticular wax coverage on leaves of Deschampsia antarctica as a possible adaptation to severe environmental conditions

• Elena V. Gorb,
• Iryna A. Kozeretska and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2022, 13, 807–816, doi:10.3762/bjnano.13.71

• surfaces showed a similar microstructure of the wax coverage, they differed in the thickness ratio between lower and upper wax layer. The ligule bore a very loose wax coverage composed of separate scale-like projections or clusters of them. We suppose that the two-layered wax densely covering both leaf

• hierarchical structure of the wax coverage on both leaf surfaces is described in D. antarctica for the first time. Keywords: cryo-SEM; microstructure; plant; surface; wax projection; Introduction The Antarctic hair grass Deschampsia antarctica É. Desv. (Poaceae) is one of the only two flowering plants native

• epicuticular wax coverage on the leaf surfaces in the adaptation of D. antarctica to the severe Antarctic environment. Additionally, the results obtained from this highly specialized plant species might be potentially interesting for biomimetics of technical surfaces or surface coatings exposed to similar

Polarity in cuticular ridge development and insect attachment on leaf surfaces of Schismatoglottis calyptrata (Araceae)

• Venkata A. Surapaneni,
• Tobias Aust,
• Thomas Speck and
• Marc Thielen

Beilstein J. Nanotechnol. 2021, 12, 1326–1338, doi:10.3762/bjnano.12.98

• .12.98 Abstract The plant cuticle is a multifunctional barrier that separates the organs of the plant from the surrounding environment. Cuticular ridges are microscale wrinkle-like cuticular protrusions that occur on many flower and leaf surfaces. These microscopic ridges can help against pest insects by

• reducing the frictional forces experienced when they walk on the leaves and might also provide mechanical stability to the growing plant organs. Here, we have studied the development of cuticular ridges on adaxial leaf surfaces of the tropical Araceae Schismatoglottis calyptrata. We used polymer replicas

• of adaxial leaf surfaces at various ontogenetic stages to study the morphological changes occurring on the leaf surfaces. We characterized the replica surfaces by using confocal laser scanning microscopy and commercial surface analysis software. The development of cuticular ridges is polar and the

Surfactant-induced enhancement of droplet adhesion in superhydrophobic soybean (Glycine max L.) leaves

• Oliver Hagedorn,
• Ingo Fleute-Schlachter,
• Hans Georg Mainx,
• Viktoria Zeisler-Diehl and
• Kerstin Koch

Beilstein J. Nanotechnol. 2017, 8, 2345–2356, doi:10.3762/bjnano.8.234

• applied droplets, even on superhydrophobic leaves, to reduce undesirable soil contamination by roll-off of agrochemical formulations from the plant surfaces. The wettability and morphology of soybean (Glycine max L.) leaf surfaces before and after treatment with six different surfactants (Agnique® SBO10

• epicuticular wax showed that 1-triacontanol (C30H61OH) is the main wax component of the soybean leaf surfaces. A water contact angle (CA) of 162.4° (σ = 3.6°) and tilting angle (TA) of 20.9° (σ = 10.0°) were found. Adherence of pure water droplets on the superhydrophobic leaves is supported by the hydrophilic

• mechanical stability [5]. Furthermore, the cuticle interacts with its biotic environment and plays a crucial role for insect signaling [6] and insect attachment [7][8][9]. The leaf surfaces are composed of epidermis cells covered by a cuticle, which is a continuous extracellular membrane on primary plant

Biological and biomimetic materials and surfaces

• Stanislav Gorb and
• Thomas Speck

Beilstein J. Nanotechnol. 2017, 8, 403–407, doi:10.3762/bjnano.8.42

• (Nelumbo nucifera) and Tropaeolum (Tropaeolum majus). Interestingly, with the rolling off of water droplets, dirt particles as well as fungus spores and bacteria are also very efficiently removed from the leaf surfaces as they are more tightly attached to the water droplet than to the leaf surface. The

• plant species were always clean whereas the surfaces of other species were always dirty. Surprisingly the smooth, wettable leaf surfaces were markedly dirty, whereas the water-repellent, hydrophobic leaf surfaces with microscale roughness were always clean. More than 40 years ago he verified this

Innovations from the “ivory tower”: Wilhelm Barthlott and the paradigm shift in surface science

• Christoph Neinhuis

Beilstein J. Nanotechnol. 2017, 8, 394–402, doi:10.3762/bjnano.8.41

• leaf surfaces [12] (Figure 7). This was elaborated in more detail later and the possibility of a technical application was already indicated [14]. Some years later, now appointed as professor for botany at the University of Bonn, Wilhelm Barthlott resumed this research. This was the time when I entered

When the going gets rough – studying the effect of surface roughness on the adhesive abilities of tree frogs

• Niall Crawford,
• Thomas Endlein,
• Jonathan T. Pham,
• Mathis Riehle and
• W. Jon P. Barnes

Beilstein J. Nanotechnol. 2016, 7, 2116–2131, doi:10.3762/bjnano.7.201

• will have a roughness that reflects the size of the component particles (e.g., sand grains in sandstone) [7]. They may also contain cracks, lumps and ridges which increase their roughness still further. Leaf surfaces may be relatively smooth, but their veins give high amplitude ridges that are

Surface roughness rather than surface chemistry essentially affects insect adhesion

• Matt W. England,
• Tomoya Sato,
• Makoto Yagihashi,
• Atsushi Hozumi,
• Stanislav N. Gorb and
• Elena V. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1471–1479, doi:10.3762/bjnano.7.139

• and experimental designs were used. In some of these studies, insect species that are strongly specialized to host plants whose leaf surfaces have very specific surface energies (water CA about 80°), such as the beetle Galerucella nympheae which lives on the leaf surface of the water lily, the maximum

Influence of ambient humidity on the attachment ability of ladybird beetles (Coccinella septempunctata)

• Lars Heepe,
• Jonas O. Wolff and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 1322–1329, doi:10.3762/bjnano.7.123

• humidity close to leaf surfaces ranges between 30% and 75% [57]. It is probable that the insects’ adhesive pad is adapted to work most efficient under these conditions. Finally, comparing absolute values in the attachment forces of C. septempunctata beetles, we found evidence for a sexual dimorphism. Male

Measuring air layer volumes retained by submerged floating-ferns Salvinia and biomimetic superhydrophobic surfaces

• Matthias J. Mayser,
• Holger F. Bohn,
• Meike Reker and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2014, 5, 812–821, doi:10.3762/bjnano.5.93

• biomimetic applications like drag reduction in ship coatings of up to 30%. Here we present a novel method for measuring air volumes and air loss under water. We recorded the buoyancy force of the air layer on leaf surfaces of four different Salvinia species and on one biomimetic surface using a highly

• and 700 mg. Schematic drawing showing the structural parameters acquired from microscopic images of Salvinia leaf surfaces: trichome height H, trichome length L, emergence length lE, egg beater shape length lC, hair length lH, emergence base diameter dEb, emergence tip diameter dEt, egg beater shape

Recrystallization of tubules from natural lotus (Nelumbo nucifera) wax on a Au(111) surface

• Sujit Kumar Dora and
• Klaus Wandelt

Beilstein J. Nanotechnol. 2011, 2, 261–267, doi:10.3762/bjnano.2.30

• also the question whether HOPG is in fact a useful substrate in order to mimic natural leaf surfaces, which is actually often done, because on natural leaves no such preferentially vertical orientation is found [7]. Conclusion We have performed the first study of the growth of nonacosan-10-ol tubules

• leaf surfaces. Experimental The nonacosan-10-ol wax materials, which were extracted with chloroform from lotus (Nelumbo nucifera) leaves, were obtained from the Nees Institute for Biodiversity of Plants at Bonn University. These wax materials, which were used in all our experiments, are actually a

Superhydrophobicity in perfection: the outstanding properties of the lotus leaf

• Hans J. Ensikat,
• Petra Ditsche-Kuru,
• Christoph Neinhuis and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2011, 2, 152–161, doi:10.3762/bjnano.2.19

• measurements are the standard tool for the determination of hydrophobicity. But the measurement of very high contact angles is often inaccurate due to difficulties in the determination of the exact drop shape [16], particularly on uneven leaf surfaces. For many superhydrophobic plant surfaces, the contact

• material, which is too fragile for most technical applications. A different architecture is found on some species with hairy leaf surfaces. The water fern (some species of the genus Salvinia) and Pistia stratioides leaves retain a relatively thick air layer between hydrophobic hairs when submersed in water

• embedded sample. Assuming a contact angle of >140°, for example, the area of heterogeneous contact between single papillae and water (marks) is small in comparison to the epidermis cell area. SEM images of the papillose leaf surfaces of Nelumbo nucifera (Lotus) (a), Euphorbia myrsinites (b), Colocasia