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

• the hierarchically structured surface of a lotus leaf. The first level of the surface structure consists of papillae formed by epidermal cells with a height and diameter of several microns. c) This structure is covered by wax crystals, leading to the extreme superhydrophobicity of the surface

Ultraviolet patterns of flowers revealed in polymer replica – caused by surface architecture

• Anna J. Schulte,
• Matthias Mail,
• Lisa A. Hahn and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2019, 10, 459–466, doi:10.3762/bjnano.10.45

• have been found in leaves, petals or seeds [17][18][19]. Whitney et al. [20] reported, for example, that this iridescence acts as a cue for pollinators and has also assumed such an effect in the UV-range. However, the influence of the plant surface structure – especially papillae – on UV-reflection up

• to now has not been studied in detail. Barthlott and Ehler [21] state that convex-shaped cells like papillae are the most common architecture in the surface structure of flowers. The parameters of these cells, such as height, diameter and tip radius, are as diverse as the arrangements of the

• cuticular foldings on top [21]. Barthlott et al. provided definitions and examples of such surface structures [1][21]. The surfaces of the three species investigated in this work possess papillae with heights between 20 µm and 80 µm and consist of convex-shaped cells. Different studies have found that

Biological and biomimetic materials and surfaces

• Stanislav Gorb and
• Thomas Speck

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

• study of tongue surfaces in nine frog species [17]. All examined species bear microscopical papillae, but different species have microstructure of different shape. The specific microstructure might presumably contribute to the particular adhesive performance of different frog species and may correlate

Frog tongue surface microstructures: functional and evolutionary patterns

• Thomas Kleinteich and
• Stanislav N. Gorb

Beilstein J. Nanotechnol. 2016, 7, 893–903, doi:10.3762/bjnano.7.81

• surface in nine different frog species, comprising eight different taxa, i.e., the Alytidae, Bombinatoridae, Megophryidae, Hylidae, Ceratophryidae, Ranidae, Bufonidae, and Dendrobatidae. In all species examined herein, we found fungiform and filiform papillae on the tongue surface. Further, we observed a

• high degree of variation among tongues in different frogs. These differences can be seen in the size and shape of the papillae, in the fine-structures on the papillae, as well as in the three-dimensional organization of subsurface tissues. Notably, the fine-structures on the filiform papillae in frogs

• , other mechanisms at the interface between a frog tongue and a target will have an important impact on tongue adhesiveness [7]. Frog tongues are known to have two types of papillae on their surface. So-called fungiform papillae (type 1) are surrounded by numerous, smaller filiform papillae (type 2) [8

The surface microstructure of cusps and leaflets in rabbit and mouse heart valves

• Xia Ye,
• Bharat Bhushan,
• Ming Zhou and
• Weining Lei

Beilstein J. Nanotechnol. 2014, 5, 622–629, doi:10.3762/bjnano.5.73

• structure is also present on the surface of the mitral valve leaflets. Namely the distribution of the nano-scale cilia structure on the micron papillae is similar to the distribution of the microstructure on the surface of the aortic valve cusps. Without treatment by heparin there is a lot of mucus attached

Impact of cell shape in hierarchically structured plant surfaces on the attachment of male Colorado potato beetles (Leptinotarsa decemlineata)

• Bettina Prüm,
• Robin Seidel,
• Holger Florian Bohn and
• Thomas Speck

Beilstein J. Nanotechnol. 2012, 3, 57–64, doi:10.3762/bjnano.3.7

• interaction; papillae; structure–function relationship; Introduction In plants the cuticle constitutes the outermost layer of the plant body and provides the direct interface to the environment. The cuticle is known to show multifaceted surface structuring and to serve different functions. Besides

• height, of the cell curvature (aspect ratio β = width/height. convex: 10 > β > 3; papillae: 1.5 > β > 0.5; the height of cell curvature in tabular cells is close to zero and therefore this description cannot be applied) modified after Barthlott [4] and reviewed by Ehler [1]. On the level of superimposed

Hierarchically structured superhydrophobic flowers with low hysteresis of the wild pansy (Viola tricolor) – new design principles for biomimetic materials

• Anna J. Schulte,
• Damian M. Droste,
• Kerstin Koch and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2011, 2, 228–236, doi:10.3762/bjnano.2.27

• characterized by micro papillae with cuticular folds on top. In contrast to the lotus surface with air pocket formation between cell papilla, wax crystals and salient water droplets [18], the petal surface seems to prevent air pocket formation and droplets penetrate into the cuticular folds by capillary forces

• folds on the papillae top, can be precisely reproduced and are suitable for the industrial production in large area foil imprinting processes. In contrast, the hierarchically organized structures of the lotus leaf are composed of micropapillae with randomly distributed tubules on top. The development of

• an extremely high aspect ratio (ar) can be replicated [29]. In this study, we present the superhydrophobic surface of the wild pansy Viola tricolor (Figure 1), with a low TA and discuss the influence of papillae morphology and the dimensions of cuticular folding on the petal wetting state. To this

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

• density of the papillae are the basis for the extremely reduced contact area between surface and water drops. The exceptional dense layer of very small epicuticular wax tubules is a result of their unique chemical composition. The mechanical robustness of the papillae and the wax tubules reduce damage and

• lower epidermis. The lotus plant has successfully developed an excellent protection for this delicate epistomatic surface of its leaves. Keywords: epicuticular wax; leaf surface; Lotus effect; papillae; water repellency; Introduction Since the introduction of the ‘Lotus concept’ in 1992 [1][2], the

• structure consisting of papillae with a dense coating of agglomerated wax tubules, which is the basis for the famous superhydrophobicity (Figure 1). However, a hierarchical surface structure which induces strong water repellency and contact angles above 150° is not a special feature of lotus leaves. It has

Biomimetics inspired surfaces for drag reduction and oleophobicity/philicity

• Bharat Bhushan

Beilstein J. Nanotechnol. 2011, 2, 66–84, doi:10.3762/bjnano.2.9

• rough due to so-called papillose epidermal cells, which form papillae or microasperities. In addition to the microscale roughness, the surface of the papillae is also rough, with nanoscale asperities composed of three-dimensional epicuticular waxes which are long chain hydrocarbons and hydrophobic. The

• sector-like scales with diameters of 4–5 mm covered by papillae 100–300 μm in length and 30–40 µm in width [18]. Shark skin, which is a model from nature for a low drag surface, is covered by very small individual tooth-like scales called dermal denticles (little skin teeth), ribbed with longitudinal