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Chitin, the second most abundant biopolymer after cellulose, is an important resource for biosourced materials. The global demand for chitin is rapidly increasing, however, the majority of industrial chitin is sourced from crustacean shells, which may be less accessible in regions without seafood waste. Therefore, it is crucial to explore alternative chitin sources, such as those derived from beetles and other arthropods. This study investigated chitin extraction from nine species of Curculionidae (true weevils), which are recognized as crop pests. The extraction process and yields were described, and the isolated chitin was characterized by SEM, IR spectroscopy, elemental analysis, XRD, and ash and water content measurements. This work highlights the potential of Curculionidae as an alternative chitin source. [ABSTRACT FROM AUTHOR]

Insects, renowned for their abundant and renewable biomass, stand at the forefront of biomimicry-inspired research and offer promising alternatives for chitin and chitosan production considering mounting environmental concerns and the inherent limitations of conventional sources. This comprehensive review provides a meticulous exploration of the current state of insect-derived chitin and chitosan, focusing on their sources, production methods, characterization, physical and chemical properties, and emerging biomedical applications. Abundant insect sources of chitin and chitosan, from the Lepidoptera, Coleoptera, Orthoptera, Hymenoptera, Diptera, Hemiptera, Dictyoptera, Odonata, and Ephemeroptera orders, were comprehensively summarized. A variety of characterization techniques, including spectroscopy, chromatography, and microscopy, were used to reveal their physical and chemical properties like molecular weight, degree of deacetylation, and crystallinity, laying a solid foundation for their wide application, especially for the biomimetic design process. The examination of insect-derived chitin and chitosan extends into a wide realm of biomedical applications, highlighting their unique advantages in wound healing, tissue engineering, drug delivery, and antimicrobial therapies. Their intrinsic biocompatibility and antimicrobial properties position them as promising candidates for innovative solutions in diverse medical interventions. [ABSTRACT FROM AUTHOR]

The lack of drinkable water is one of the most significant risks for the future of the humanity. Estimates show that in the near future, this risk will become the origin of massive migrations leading to humanitarian disaster. As consequence, the development of solutions to provide water is becoming ever more critical, and a significant effort is devoted to identifying new sources of water. Among the developed strategies, fog harvesting, which takes advantage of atmospheric water to provide potable water, is a solution of interest due to its potential in sustainable development. Unfortunately, this approach suffers from low yield. In the present work, we take inspiration from living species to design and elaborate surfaces with high potential for water harvesting applications. This work takes advantage of 3D-printing and post-printing functionalization to elaborate a strategy that allows modelling, printing, and functionalization of surfaces to yield parahydrophobic behavior. The roughness and surface morphology of the prepared surfaces were investigated. These characteristics were then related to the observed wettability and potential of the functionalized interfaces for water harvesting applications. This work highlights significant variations in surface wettability via surface modification; strong hydrophobic behavior was observed via modification with linear carboxylic acids particularly for surfaces bearing vertical blades (plate with vertical blades and grid with vertical blades). [ABSTRACT FROM AUTHOR]

Copper based layers were fabricated on gold/silicon (100) substrates by using square pulse electrodeposition at different deposition temperatures. The predominant crystalline plane on Cu2O samples at temperatures higher than 30 °C is (111), which is the most hydrophobic facet of Cu2O cubic structure. Different crystallite structures such as semivertical leaves, fractal trees, and octahedral pyramids were formed on the surface. These water‐repellent samples have hierarchical structures, including octahedral pyramid microstructures with small spherical balls on them and well‐branched micrometric vertical leaves on the surface. They provide a suitable surface for trapping air pockets inside the structure and increasing the water contact angle up to 154°. This approach may be applicable to the large‐scale preparation of water‐repellent surfaces as superhydrophobicity can be achieved in a one‐step deposition process without any secondary modifications. [ABSTRACT FROM AUTHOR]

Abstract: Tuning macroscopic behavior between a synthetic surface and the surrounding environment requires precise engineering of micro‐ and nanoscale features at the interface. As one example, the geometry and spacing of topographical structures can be manipulated to modify interfacial interactions with water. If optimized correctly, topographical features can impart macroscopic wetting behavior that goes well beyond what is expected from the chemistry of the surface materials, such as strong hydrophobicity from intrinsically hydrophilic materials. However, developed techniques such as templating or nano‐lithography require significant processing times and are often ill‐suited for in situ applications. This work shows that polymeric interfaces with regular, ordered topographical features can be generated using a rapid in situ photopolymerization technique that requires no templating nor additional processing to generate or manipulate surface features. Maximizing the local differential in polymerization‐induced shrinkage between heterogeneous domains results in the formation of robust 3D surface features. Furthermore, the spacing and density of these features can be optimized through the phase separation process, yielding surfaces with variable wetting (θw ≈ 90–130°). These results demonstrate that template‐ and mask‐less surface patterning is possible with rapid polymerization techniques and that it can be easily manipulated to vary surface wetting behavior. [ABSTRACT FROM AUTHOR]

This work describes the synthesis and subsequent electrodeposition of 4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophene (cyclopentadithiophene) monomers di‐substituted with alkyl chains. Each monomer was electropolymerized in solution to observe their capacity at creating well‐structured, rough surfaces. The length of the alkyl chain substituent has a significant influence on the overall surface morphology and wetting behavior after electropolymerization. In the case of nonsubstituted cyclopentadithiophene monomers or those with short alkyl (methyl and ethyl) substituents, the polymerization proceeds readily, forming rough surfaces that follow the Wenzel regime of wetting. In these cases, the surfaces were decorated with globular agglomerates and woven mat features. The measured surface roughness decreases with alkyl chain length as steric hindrance caused by the alkyl substituents limits electropolymerization. As the alkyl chain substituent increases to propyl chain length and beyond, the increase in steric hindrance is so significant that the surface morphology formed during electrodeposition is primarily due to π‐stacking interactions between very short oligomers formed in solution. With propyl and butyl substituents, nanofold morphology is observed, leading to surfaces with much higher contact angles with water (~132°) that follow the Cassie‐Baxter regime of wetting. This type of surface morphology has only been demonstrated one other time and with the use of fluorinated constituents. This work exposes a mild, fluorine‐free synthetic route to creating nanofold‐decorated surfaces. [ABSTRACT FROM AUTHOR]

The formation of highly ordered surface structures is fundamental for various applications. Due to their rapidity of implementation and their cost, templateless processes are extremely interesting alternatives to the use of templates or lithographic processes. With the aim to prepare porous structures such as nanotubes, templateless electropolymerization was found to be a unique process. Based on previous works, we have synthesized 3,4-naphthalenedioxythiophene (NaPhDOT) monomers substituted with alkyl chains (n=2 to 10), phenyl and naphthalene substituents. In particular, NaphDOT substituted with naphthalene (NaphDOT−Na) leads for the first time to relatively densely packed nanorings while their internal diameter is controllable with the number of deposition scans. Compared to previous works, which lead to nanotubes from non-substituted NaphDOT and 3,4-phenylenedioxythiophene substituted with naphthalene (PheDOT−Na), with NaphDOT−Na we observe a very important decrease in the polymer growth. As a consequence, only the initial peripherical nucleation around the gas bubbles is possible, leading to nanorings, because their growth into nanotubes is impeded by their low conductivity. [ABSTRACT FROM AUTHOR]

Vegetal and animal reigns offer many examples of surfaces with surprising and interesting wetting properties. As example, springtails present superoleophobic properties allowing to live in soil and Lotus leaves show self-cleaning ability even under rainfalls. Indeed, it is known that self-cleaning properties can help to remove dust and particles during rainfalls and as a consequence to clean the surface. The bioinspiration of these surface properties is of a real interest for industrial applications in the nanotechnology field such as photovoltaic systems or anti corrosive material. Here, we use a strategy based on electropolymerization to obtain these properties. The Staudinger-Vilarrasa reaction is used to prepare innovative 3,4-ethylenedioxypyrrole (EDOP) monomers with fluorinated chains. Using C6F13 or C8F17 chains, the polymer surfaces formed after electrodeposition show superhydrophobic and superoleophobic features. Here we study the surface wettability depending on the surface energy (based on the perfluorinated chain length), the surface roughness and morphology. [ABSTRACT FROM AUTHOR]

Graffiti can sometimes be a problem when put in an inappropriate place. We looked at a means to prevent such inconvenience. In this work, we explore the possibility of developing surfaces with controlled wettability. If the paint does not spread, the graffiti does not stay. Here, the synthesis and electrodeposition of original 3,4-ethylenedioxythiophene (EDOT) with perfluorinated nucleolipids (ante approach) is reported. The elaboration of similar surfaces using post functionalization is also described. All the prepared surfaces were then investigated for their roughness, wettability, and morphology. Highly hydrophobic features are reported (θ = 137°) and oleophobic properties are also reported (θ = 110°) showing real potential for the control of surface wettability and for potential anti-graffiti applications, consequently. The surfaces obtained with the ante approach are rougher and more hydrophobic. [ABSTRACT FROM AUTHOR]

The control of surface wettability is a key parameter for many application fields (materials, biomedical engineering, etc.). In this work, a new and efficient strategy to synthesize monomers suitable for hydrophobic surface elaboration is reported. This original approach allows the preparation of monomers and, as a consequence, surfaces bearing two different substituents by using the Staudinger reductive amination and amidification. Rough conducting polymer films were prepared by electropolymerization. The original surfaces reported here are highly structured surfaces with tunable hydrophobic features. Depending on the grafted chains, the surfaces are hydrophilic (PEDOT-Benz-Ph, θ =80°; PEDOT=poly(3,4-ethylenedioxythiophene)), hydrophobic (PEDOT-Benz-C12, θ=132°), or even superhydrophobic (PEDOT-Benz-F8, θ=152° (α=5.0°, H=0.3°). [ABSTRACT FROM AUTHOR]

Here, the combination of both the Staudinger reductive amination and amidification to prepare highly hydrophobic surfaces is reported for the first time. This approach has been studied for surface ante and post-deposition modification. In the ante-deposition approach, the combination of both the reactions allows to develop a one-pot new monomer bearing two different side chains (heterobifunctional surface). The developed monomer has been successfully polymerized and leads to hydrophobic surface (θ > 110°). Similar modifications performed as post-treatment lead to highly hydrophobic feature (θ > 120°). The difference between the ante and post-deposition modification is investigated for their roughness and morphologies. The results of this work allow explaining this difference on surface feature and show quality and drawback of both ante and post-deposition strategies. [ABSTRACT FROM AUTHOR]

In this work, novel 3,4-phenylenedioxythiophene (PhEDOT) monomers with alkyl, branched, and aromatic substituents were synthesized and tested for their efficacy at forming surfaces with unique wetting properties and surface morphology without the aid of surfactants. Monomers with a naphthalene substituent clearly showed the highest capacity to stabilize gas bubbles (O2 or H2) formed in solution during electrodeposition from trace water, resulting in the formation of nanotubes. Variation in the resulting density, diameter, and height of nanotubes was demonstrated by varying the electropolymerization protocol, conditions, or electrolyte used. The wetting induced by the nanotube formation results in the surfaces formed having both high contact angles with water (ϑW) and strong adhesion, despite all polymers being intrinsically hydrophilic. This one-step and easily tunable approach to nanotube formation has potential to advance applications in membrane design, water transport and harvesting, as well as sensor design. [ABSTRACT FROM AUTHOR]

In this work, platform post-modifications using the Huisgen reaction are reported. Various platform surfaces are developed and post-functionalized with aryl side chains. The development of different conducting polymer platforms allows the study of the impact of the starting surface on the modified surface properties. Also in this work, different aryl side chains are investigated (with one, two, three, or four aromatic rings) in order to investigate the impact of the side chain on the final surface feature. All the combinations (surface vs aryl side chain) are investigated for their wettability. Highly hydrophobic features are observed with apparent contact angles θ higher than 140° and extremely high water adhesion. Surface morphologies are also investigated and important changes in morphology are observed after surface post-functionalization. The reported strategy to develop various highly hydrophobic surfaces with high water adhesion feature can be a powerful strategy for water trap elaboration. [ABSTRACT FROM AUTHOR]

Surface modifications are keys for a great number of applications. In order to perfectly control the surface properties, it is important to control the modification pathways. Two general pathways can be described in order to introduce modification on surfaces: the post-strategies and the ante-strategies. In this work, we focus on the comparison between the Huisgen and the Staudinger-Vilarrasa reaction for both post-surface and ante-surface modifications. Here, we focused on the possibility to use both two reactions to obtain superhydrophobic and oleophobic properties. This work includes monomer synthesis, surface modifications with alkyl, aryl or perfluoroalkyl chain. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The formation of materials with switchable wettability is extremely important for various applications such as in separation membranes or liquid transportation. Here, we report for the first time the use of imine bonds in order to prepare switchable hydrophobic/hydrophilic surfaces. Based on a poly(3,4-ethylenedioxythiophene) surface bearing amino groups, imination reaction allows for reversible functionalization of surfaces with various carbonyl groups. Here, surfaces functionalization induces high hydrophobic properties while the surface structures are preserved. This reaction can be a choice method to prepare switchable surfaces for a large range of applications. [ABSTRACT FROM AUTHOR]

Postfunctionalization is a key tool for the elaboration of hydrophobic surfaces. For that purpose, the elaboration of surfaces suitable for the Huisgen reaction allows for functionalization with various hydrophobic side chains. Here the synthesis of azido or alkyne monomers is reported to prepare platform surfaces suitable for click chemistry. The surface hydrophobicity and morphology are investigated. Superhydrophobic and parahydrophobic properties are obtained depending on the starting monomer and the molecule used for the postfunctionalization. [ABSTRACT FROM AUTHOR]

Reported for the first time is the use of click chemistry to make layer-by-layer multiple post -functionalization treatments. The use of triazole as a platform for the post -functionalization allows the introduction of new clickable structures on the surface. The layer-by-layer strategy by means of click chemistry allows the introduction of both multiple and/or different consecutive modifications on the surface and multicharged species. Herein it consists of the use of molecules functionalized by a 1-azido group and propargyl bromide to deposit functionalized triazolium-type charged oligomers on the substrate. Moreover, different functional groups can be introduced at each step, which amplifies the use of this strategy for many potential applications. Here, to give an example of applications, that strategy is used to introduce alkyl chains and obtain highly hydrophobic materials. Moreover, it is shown that the surface morphology can also change after each treatment. [ABSTRACT FROM AUTHOR]

An ionic polymeric network based on a disulfide diphosphonium ionic liquid and a tetraanion was designed and studied in order to explore two self-assembly strategies: weak covalent bonds and ionic interactions. When the disulfide diphosphonium ionic liquid was complexed with a multianion, a crosslinked network structure was obtained. By applying external stimuli such as temperature or inducing a mild redox reaction, the network could be disrupted. The disruption/formation of the network is reversible. The thermal, rheological and electrochemical properties were also studied to further characterize these materials and to better understand the resulting structure–property relationships. [ABSTRACT FROM AUTHOR]

Back Cover: This cover page shows how the Staudinger reductive amination and amidification can be used to change, by introducing bifunctional groups, the surface morphology and hydrophobicity. This is reported by Emna El Kout, Rawia Ben Trad, Mejda El Kateb, Mohammed Beji, Jean‐Pierre Laugier, Guilhem Godeau,* Frédéric Guittard, and Thierry Darmanin* in article number 1700250. [ABSTRACT FROM AUTHOR]

Back Cover: The cover image describes different strategies to modify structured conducting polymer films with the Huisgen reaction in order to introduce aromatic groups and lead to high water adhesion. Further details can be found in the article by Guilhem Godeau,* Jessica N'Na, Frédéric Guittard, and Thierry Darmanin* on page 2107. [ABSTRACT FROM AUTHOR]

Molecular motors transport various cargoes including vesicles, proteins and mRNAs, to distinct intracellular compartments. A significant challenge in the field of nanotechnology is to improve drug nuclear delivery by engineering nanocarriers transported by cytoskeletal motors. However, suitable in vivo models to assay transport and delivery efficiency remain very limited. Here, we develop a fast and genetically tractable assay to test the efficiency and dynamics of fluospheres (FS) using microinjection into Drosophila oocytes coupled with time-lapse microscopy. We designed dynein motor driven FS using a collection of dynein light chain 8 (LC8) peptide binding motifs as molecular linkers and characterized in real time the efficiency of the FS movement according to its linker’s sequence. Results show that the conserved LC8 binding motif allows fast perinuclear nanoparticle's accumulation in a microtubule and dynein dependent mechanism. These data reveal the Drosophila oocyte as a new valuable tool for the design of motor driven nanovectors. [ABSTRACT FROM AUTHOR]