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The Special Issue “Synthesis, Functionalization and Applications of Nanocarbons” starts from the growing interest of the scientific community in carbon-based materials and the various applications of these versatile compounds [...]

A simple and cheap filter paper-based SERS substrate has been developed for the sensing of tetracycline (TC) traces. In fact, antibiotics could represent a danger for environment and human health and TC is, in detail, one of the most wide-spread antibiotics entering the food chain and as water contaminant. According to this aim, Ag nanodisks (AgNDs) synthesis procedure was designed for tailoring the plasmonic peak position and, so, the SERS effect. Synthetized AgNDs were then used to simply decorate the surface of common filter paper, chosen because of its biocompatible, porosity and cheapness features. The obtained substrates based on filter paper and AgNDs allow the fast and easy analysis of aqueous solution containing first methylene blue used as standard and then TC samples. Fixed volume (20 μL) of TC solutions at different concentrations was simply dropped on the SERS support. The SERS spectrum was acquired before the complete water evaporation allowing TC detection down to the concentration of 10−9 M in aqueous solution. The results demonstrated that the SERS substrate obtained with the proposed facile, low-cost and relatively green fabrication process and the possibility to tune the plasmon excitation can be implemented for TC low concentration samples.

A strategy to improve organic photovoltaics, and to enhance the device efficiency, builds on the design of interfacial layered (IFL) materials implementing the performance of the photoactive acceptor/donor system. A novel IFL blend has been engineered by a supramolecular organic-inorganic heterojunction integrating polyoxometalate-bis-pyrene (pyrPOM) receptors that can selectively bind fullerene-based acceptors through π-π interactions and in particular the most used phenyl-C61-butyric acid methyl ester (PCBM) PCBM. The resulting pyrPOM@PCBM IFL, assembled by means of the Langmuir-Blodgett approach, has been fully characterized both in solution and on solid supports by means of the Langmuir-Schaefer method, featuring a high dielectric function, good polarizability and piezo-responsive behavior, which suggest ferroelectric properties. An organic solar cell is realized interposing the IFL between poly(3-hexylthiophene) (P3HT) as polymer donor and the PCBM acceptor layers, thus enhancing the open circuit voltage of the solar device by about 34% under an applied bias of ±5 V. © 2021 The Royal Society of Chemistry.

Fin dall’età del Ferro in tutta la Puglia meridionale è ben documentata la presenza di ceramiche fini di produzione locale riconducibili a forme di artigianato specializzato. Indicatori di attività produttive si possono riconoscere in numerosi siti dell’VIII e VII secolo e, a partire dal VI sec. a.C., sono ben documentate le fornaci per il vasellame, come dimostra soprattutto la concentrazione di strutture pirotecnologiche nel settore settentrionale dell’abitato di Oria. Nel IV e III sec. a.C., con il progressivo strutturarsi degli insediamenti urbani del Salento messapico si sviluppa ulteriormente l’organizzazione degli impianti destinati alla produzione delle ceramiche fini. A fronte di notizie piuttosto modeste relativamente alle singole officine, dati di notevole interesse provengono dalle analisi archeometriche condotte sui pigmenti delle ceramiche a fasce ed a vernice bruna. Attraverso le indagini spettroscopiche, infatti, è possibile definire le caratteristiche chimico-fisiche della decorazione e, sulla base di queste, ipotizzare le condizioni di cottura dei vasi in riferimento al tipo di ambiente ed alla temperatura. Il confronto tra il vasellame dell’età del Ferro e quello delle fasi tardo-classiche ed ellenistiche consente di illustrare alcuni aspetti nella trasformazione della produzione: l’artigianato specializzato evolve verso forme produttive in cui l’ottimizzazione dei processi permette di perseguire simultaneamente risultati quantitativi e qualitativi.

Carbon nanomaterials are a group of materials characterized by sp2/sp3 carbon backbone which, combined with surface atoms and/or chemical groups, ensures peculiar physical chemical features for a wide range of applications. Among these materials, carbon dots and carbon nanoparticles belong to carbon nanomaterials with a few nanometer dimensions. In this work, carbon nanoparticles were produced from spent coffee grounds as sustainable carbon source through a simple, cheap and eco-friendly procedure according to an oxidation process (at controlled temperature) driven by hydrogen peroxide. Atomic Force Microscope (AFM) and fluorescence, UV-Vis absorption, FT-IR and Raman spectroscopy were used to assess the formation of carbon nanomaterials of about 10 nm with the typical emission and absorption properties of carbon dots and peculiar surface features. In fact, the presence of heteroatoms, i.e., phosphorus, and the carbonyl/carboxyl surface groups on carbon nanoparticles, was proposed to confer peculiar properties allowing the fast Mn(VII) reduction to Mn(II) at neutral pH and the Cr(VI) reduction to Cr(III) in weak acid aqueous media.

In recent years, the presence of numerous xenobiotic substances, such as antibiotics, has been detected in water environments. They can be considered as environmental contaminants, even if their effect on human health has yet to be totally understood. Several approaches have been studied for the removal of these kinds of pollutants. Among these compounds, tetracycline (TC), a broad-spectrum antibiotic, is one of the most commonly found in water due to its widespread use. In the context of reducing the presence of TC in aqueous solution, in this contribution, a composite catalyst based on zinc oxide (ZnO) and iron oxide (&gamma, Fe2O3) was developed and its photocatalytic properties were investigated. The catalytic materials were synthesized by a microwave-assisted aqueous solution method and characterized by Field Emission Scanning Electron Microscope (FESEM), X-Ray Fluorescence (XRF) and Brunauer&minus, Emmett&minus, Teller (BET) analysis. The TC concentration was evaluated by spectrophotometer measurements at specific time intervals. The performed photocatalytic experiments clearly demonstrated that the ZnO/&gamma, Fe2O3 composite catalyst presents significant photocatalytic activity, indeed a TC degradation efficiency of 88.52% was registered after 150 min. The presence of iron oxide in the structure of the catalyst enhances both the surface area and the pore volume, facilitating the adsorption of the analyte on the surface of nanostructures, a fundamental phase to optimize a photodegradation process. Moreover, ZnO was found to play the key role in the photocatalytic process assisted by &gamma, Fe2O3 which enhanced the TC degradation efficiency by 20%.

This work reports on the spectroscopic properties and gas sensing performances of cobalt bis-porphyrin derivative ((Co-H)Por2) in a thin films form obtained by Langmuir–Schafer (LS) method towards Volatile Organic Compounds (VOCs) and an oxidizing gas in a Magneto-Optical Surface Plasmon Resonance (MO-SPR) configuration. In particular the optical and spectroscopic properties of (Co-H)Por2 multilayers deposited onto proper Au/Co/Au magneto-plasmonic (MP) transducers were inspected in dry air conditions and after exposure to different analyte gas concentrations. The molecular organization of these thin films deposited by Langmuir–Schafer technique has been investigated and a comparison between the MOSPR experimental data and simulation has been also reported. In order to validate our experimental results and obtain further insight into the physical mechanism of interaction between the organometallic molecules and magneto plasmonic nanostructured systems, numerical simulations based on Finite Element Method (FEM) techniques, have been performed. The optical and magneto-optical properties of these hybrid systems have been theoretically analyzed to confirm the experimental outcomes. Finally, a peculiar sensitivity of the MOSPR sensing probe in respect to investigated analytes has been recorded.

Parabens and phenoxyethanol are chemical compounds widely used as preservatives and antimicrobial agents in cosmetic and personal care products. The issue of their effect on human and environmental health is a particularly topical and relevant one that many national and international agencies reported about the risk from the use of such compounds. In the present paper, iron doped TiO2 nanoparticles were synthetized and characterized by morphological and spectroscopic techniques. The proposed synthesis was designed to improve the photocatalytic activity of the nanostructures towards the two preservatives compounds when irradiated by a visible light, in order to optimize the effect of natural irradiation on the photodegradation of the two compounds. Preliminary photocatalytic tests showed that the analytes’ concentration in water solutions under illumination in presence of both iron-doped TiO2 and pure TiO2 decreased. A sensible enhancement of photocatalysis of both propylparaben and phenoxyethanol was recorded in presence of the Fe-doped nanostructures as a consequence of the physical and chemical properties of the catalyst.

Herein, the fabrication of multi-responsive and hierarchically organized nano-material using core-shell SrF2upconverting nanoparticles, doped with Yb3þ,Tm3þ,Nd3þincorporated into gelatin methacryloyl matrix, is reported. Upon800 nm excitation, deep monitoring of 3D-printed constructs is demonstrated.Addition of magnetic self-assembly of iron oxide nanoparticles within thehydrogel provides anisotropic structuration from the nano- to the macro-scaleand magnetic responsiveness permitting remote manipulation. The presentstudy provides a new strategy for the fabrication of a novel highly organizedmulti-responsive material using additive manufacturing, which can haveimportant implications in biomedicine.

Conformational switching induced in ethane-bridged bisporphyrins was used as a sensitive transduction method for revealing the presence of urea dissolved in water via nonenzymatic approach. Bisporphyrins were deposited on solid quartz slides by means of the spin-coating method. Molecular conformations of Zn and Ni monometalated bis-porphyrins were influenced by water solvated urea molecules and their fluorescence emission was modulated by the urea concentration. Absorption, fluorescence and Raman spectroscopies allowed the identification of supramolecular processes, which are responsible for host-guest interaction between the active layers and urea molecules. A high selectivity of the sensing mechanism was highlighted upon testing the spectroscopic responses of bis-porphyrin films to citrulline and glutamine used as interfering agents. Additionally, potential applicability was demonstrated by quantifying the urea concentration in real physiological samples proposing this new approach as a valuable alternative analytical procedure to the traditionally used enzymatic methods.

Cu,H2-bis-porphyrin (Cu,H2-Por2), in which copper porphyrin and free-base porphyrin are linked together by an ethano-bridge, was dissolved in chloroform and spread at the air/liquid subphase interface of a Langmuir trough. The bis-porphyrin derivative, floating film was characterized by reflection spectroscopy and the surface pressure of the floating film was studied as a function of the mean area per molecule. When aromatic amines are dissolved in the subphase, an evident interaction between the bis-porphyrin host and the aromatic amine guest is observed. A clear-cut variation of the profile of surface pressure vs area per molecule curve is observed. Reflection spectroscopy highlights that the aromatic amines dissolved in the subphase are able to induce the syn-to-anti conformational switching in the bis-porphyrin derivative. The Langmuir–Schaefer technique has been used to transfer the floating bis-porphyrin film (when using pure water as a subphase) to a surface plasmon resonance (SPR) substrate and the resulting device was able to detect the presence of aniline at concentrations as low as 1 nM in aqueous solution. The high selectivity of the SPR sensing device has been verified by checking the spectral response of the active layer towards other analytes dissolved in the aqueous solutions.

In the present manuscript it is reported a study carried out by means of micro-Raman and infrared spectroscopy on banknotes used in Italy during more than 50 years, since 1947 until 2001. For each specimen, three different features of the banknote (serial number, watermark and security mark) were considered and the measurements were repeated on three different banknotes of the same type. Differences were revealed in the paper banknote composition, red color used for the security mark and serial number black printing ink. Then, two certified fakes were analyzed and significant shifts on the main peak of red color pigment were revealed.

Surface enhanced Raman scattering (SERS) is largely used as a transduction method for analytes detection in liquid and vapor phase. In particular, SERS effect was promoted by a plethora of different metal and semiconducting nanoparticles (NPs) and silver and gold nanoparticles appear particularly suitable for this application. Nevertheless, silver nanoparticles intrinsic propensity to aggregate in large clusters reduces the possibility to use naked nanoparticles in SERS applications, for this reason they are usually functionalized with organic molecules. This approach inhibits the aggregation process but, on the other hand, reduces the surficial area of the NPs able to interact with the analyte molecules. In the present work, we propose a simple method to obtain surficial anisotropic Janus silver nanoparticles: octadecylamine was used to stabilize the nanoparticles and to promote the deposition of the silver nanoparticles on a solid substrate. The AgNPs/octadecylamine nanostructures showed the typical “hairy” Janus morphology and a strong SERS effect was observed when two biogenic amines, i. e. 2-phenylethylamine and tyramine, were fluxed on the solid film. SERS phenomenon was studied as a function both of the chemical structure of the fluxed amine and of the distance between the aromatic moiety and the nanoparticle allowing to propose the AgNPs/octadecylamine Janus nanoparticles as an active layer for the detection of phenylethylamine and tyramine in picomolar concentration.

Silver nanoparticles were synthesized in the presence of saccharides and ammonia (NH3) in the concentration range from 10−2 to 103 ppm to develop an optical sensor for NH3 in aqueous solutions. Ammonia affects the features of the nanoparticles obtained in a concentration-dependent manner as determined by UV–vis absorption analysis and TEM observations. Structural and morphological analysis provides the basis for the production of a colorimetric label-free sensor for ammonia. Overall, surface plasmon resonance increases when ammonia concentration rises, although the functional trend is not the same over the entire investigated ammonia concentration range. Three different ranges have been identified: very low ammonia concentrations from 0.01 to 0.2 ppm, high ammonia concentrations from 20 to 350 ppm and, most importantly, the intermediate or physiological range of ammonia from 0.5 to 10 ppm.

Time travel through 150 years of Italian postage stamp issues has allowed defining the evolution of the recurring pigments in stamp designs by means of Raman and FTIR spectroscopy. Numerous exemplars have been analyzed, covering the entire production of stamps for both the Italian Kingdom and Republic. Raman and FTIR spectra showed the changeover from Prussian blue to copper phthalocyanine inks in 1958. The entire succession for red inks was also recognized to develop from the original cinnabar to red ochre and minium and finally to red azo pigments. The changes in orange printing ink proceeded on a similar path. The first orange Italian exemplar was printed employing a mixture of chrome orange and red ochre. In 1929 this combination was replaced by azo pigments. Green stamps belonging to the first issues entailed the choice of blue and orange inks, namely chrome orange and Prussian blue. Later on, an ink composed mainly of phthalocyanine was employed as the green dye. The merging of data coming from Raman microscopy and FTIR-ATR spectroscopy, both non-destructive techniques, has allowed the characterization of stamp designs and potentially provides direct and fast evidence for the recognition of forged exemplars.

Glass micromachining is a basic technology to achieve microfluidic networks for lab-on-a-chip applications. Among several methods to microstructure glass, the simplest and most widely applied is wet chemical etching (WE). However, accurate control of the reaction conditions to perform reproducible, fast and safe glass etching is not straightforward. Herein, microwave-assisted WE is demonstrated to intensify the glass etching action under safe working and finely monitored operative conditions and to produce smooth deep channels in short processing times with reduced underetching effects.

Mixed iron-manganese oxide nanoparticles, synthesized by a simple procedure, were used to remove nickel ion from aqueous solutions. Nanostructures, prepared by using different weight percents of manganese, were characterized by transmission electron microscopy, selected area diffraction, X-ray diffraction, Raman spectroscopy, and vibrating sample magnetometry. Adsorption/desorption isotherm curves demonstrated that manganese inclusions enhance the specific surface area three times and the pores volume ten times. This feature was crucial to decontaminate both aqueous samples and food extracts from nickel ion. Efficient removal of Ni2+ was highlighted by the well-known dimethylglyoxime test and by ICP-MS analysis and the possibility of regenerating the nanostructure was obtained by a washing treatment in disodium ethylenediaminetetraacetate solution.

Summary Self-assembly of block copolymers into well-defined, ordered arrangements of chemically distinct domains is a reliable strategy for preparing tailored nanostructures. Microphase separation results from the system, minimizing repulsive interactions between dissimilar blocks and maximizing attractive interactions between similar blocks. Supramolecular methods have also achieved this separation by introducing small-molecule additives binding specifically to one block by noncovalent interactions. Here, we use halogen bonding as a supramolecular tool that directs the hierarchical self-assembly of low-molecular-weight perfluorinated molecules and diblock copolymers. Microphase separation results in a lamellar-within-cylindrical arrangement and promotes upright cylindrical alignment in films upon rapid casting and without further annealing. Such cylindrical domains with internal lamellar self-assemblies can be cleaved by solvent treatment of bulk films, resulting in separated and segmented cylindrical micelles stabilized by halogen-bond-based supramolecular crosslinks. These features, alongside the reversible nature of halogen bonding, provide a robust modular approach for nanofabrication., Graphical Abstract, Highlights • Halogen bonding small molecules to block copolymers yields hierarchical self-assembly • Fluorinated additives increase block repulsion χ and enhance microphase separation • Upright cylinder structure alignment is favored by fluorocarbon low surface energy • Segmented cylindrical micelles can be obtained by solvent treatment of bulk films, The Bigger Picture Directed self-assembly (DSA) is probably the most promising strategy for high-volume cost-effective manufacturing at the nanoscale to support the ever-growing needs of the semiconductor market. DSA exploits the spontaneous self-assembly of block copolymers onto lithographically nanopatterned surfaces, resulting in large-area fabrication of periodic nanostructures on the scale of a few tens of nanometers. Tailoring the structure, periodicity, and orientation of the block copolymer is crucial and requires control over features such as block volume fraction, immiscibility, and surface energy. Here, we use fluorocarbon additives that specifically form halogen bonds with only one of the blocks, promoting microphase separation even upon rapid casting and without subsequent solvent annealing, which, along with the reversible nature of the halogen bond, could pave the way for new self-assembly routes toward the alignment and periodicity of block copolymers and nanostructures., Halogen bonding drives the hierarchical self-assembly of low-molecular-weight perfluorinated molecules and diblock copolymers. Specifically, binding of the ditopic halogen-bond donor 1,8-diiodoperfluorooctane to pyridine nitrogens of poly(styrene)-block-poly(4-vinylpyridine) results in lamellar-within-cylindrical self-assembly and promotes upright cylindrical alignment in films. This feature, along with the reversible nature of the halogen bond, provides a robust and modular approach for nanofabrication. Thanks to the robust halogen-bond-based crosslinks, separated segmented cylindrical micelles can be obtained by solvent treatment of bulk films.

The Langmuir–Blodgett (LB) films with J aggregates of the amphiphilic MC2 merocyanine have been deeply investigated for more than two decades, mainly because of their interest for applications in photonic devices. To extend the excitation/emission wavelength range, we have studied an homologous dye, MC1, based on a shorter merocyanine chromophore, aiming at checking the ability of this compound to arrange into J aggregates within stable LB films. In this comparative MC1/MC2 investigation, we have addressed the structural and spectroscopic properties of the monomers in solution, the thermodynamic and morphological properties of the Langmuir monolayers at the air–water interface and the spectroscopic and photophysical properties, and the structural features thence obtainable, of the aggregates in the LB films. 1 H NMR experiments have shown that, in chloroform solutions, both dyes adopt planar conformations with the hydrophilic and hydrophobic groups pointing to opposite directions. Strongly attractive interactions are exhibited by both dyes towards arachidic acid in monolayers at the air– subphase interface, with a maximum stability for the 1 : 2 MC(1/2) : AA mixture. Relatively homogeneous LB multilayers have been obtained from 1 : 4 and 1 : 2 MC : AA mixtures with good transfer ratios. Absorption and emission of the LB films of MC1 are dominated by J aggregates, while those of MC2 show some H aggregate contributions too. The J aggregates of both compounds exhibit a tendency to align with the transition dipoles along the film dipping direction, only slightly tilted relative to the substrate surface; however, this tendency is more pronounced for the MC1 J aggregates. Overall, MC1 yields slightly more stable monolayers and more solid multilayers compared to MC2

This work reports on the structural and spectroscopic properties, as well as the gas-sensing performance, of ethane-bridged Zn porphyrin dimers (ZnPP) in Langmuir-Schäfer (LS) thin films toward volatile organic compounds in a magneto-optical surface plasmon resonance (MOSPR) configuration. Structural and spectroscopic properties of ethane-bridged ZnPP thin films deposited onto proper Au/Co/Au magneto-optical substrates were inspected in dry air conditions and after exposure to amine vapors by means of IR spectroscopy, scanning probe microscopy, and MOSPR techniques. The molecular organization of the thin films deposited by the LS technique is investigated. The overall results suggest the presence in all cases of mainly the anti-conformer of the investigated porphyrin dimers. The strong interaction between n-butylamine vapors at high concentration and Zn porphyrin thin layers leads to a great conformational change in the porphyrin structure, which is linked to a change in the optical anisotropy of the realized LS layer. © 2012 American Chemical Society., This work has been funded by the European Commission (NMP3-SL-2008-214107-Nanomagma), the Spanish MICINN (CSD 2008-00023, MAT 2008-06765-C02-01/NAN, MAT2010-21228), CSIC (JAE fellowship for E.F.-V.), Comunidad de Madrid (S2009/MAT–1726, S2009/TIC–1476), and FIRB-Futuro in ricerca (Nanoplasmag project- RBFR10OAI0).

Porphyrins are tetrapyrrolic macrocycles with a fascinating and multifarious variegation of properties of essential significance in up-to-date and leading technologies. From a different point of view, the Langmuir–Blodgett technique allows the immobilisation of films with an accurate regulation of molecular organisation and thickness. As a logical upshot, this manuscript concerns a substantial object of consideration in contemporary research, the utilisation of Langmuir–Blodgett multilayers of porphyrins in sensing elements for the detection of analytes in different matrices. Investigations on the morphological, optical, structural and surface characteristics of these films are remarkably related to the significant properties of sensors with the ultimate goal of rationalising the innermost intercourses between the sensing behaviour and the peculiarities and molecular organisation brought about by the deposition method. The integration of the typical electrical and optical characteristics of porphyrins with the potentialities of the Langmuir–Blodgett multilayer has originated not only encouraging projects but has afforded also certainties on the accomplishment of operative chemical sensors.

Carbon nanotubes are recent materials with an extremely appealing multiplicity of peculiar characteristics of paramount interest in contemporary advanced (nano)technologies. At the same time, the Langmuir–Blodgett technique allows to fabricate films with a substantial control and chance of modulation over thickness and molecular organisation. As a spontaneous outcome, this review deals with an actual subject of attention in up-to-date scientific investigations, i.e. the preparation, characterisation and applications of Langmuir–Blodgett films of pristine or functionalised single- or multi-walled carbon nanotubes in modern research.

Tetrapyrrolic macrocycles are largely used in the sensing of various analytes both in liquid and in gaseous phase, but the strong electronic delocalization of this class of molecules makes difficult to realize a selective active layer. To overcome this problem, in the present work it is proposed the synthesis of a supramolecular adduct of zinc oxide nanostructure and a free-base tetra- pyridyl substituted porphyrin. The electronic structure of the two organic/inorganic compounds allows to observe a surface-enhanced Raman scattering (SERS) of the porphyrin vibrational bands. This phenomenon is quenched by the presence of mercuric and cupric ions according to two different mechanisms monitored and explained by means of time resolved fluorescence spectroscopy. It was demonstrated that other substances in complex matrices, such as the food extracts, do not affect the electronic communication between ZnO and porphyrin preserving the SERS effect and minimizing the effect of interfering compounds.

Two of the most known properties of ZnO were used to improve the performance of a dye-sensitized solar cell (DSSC) using a nanoadduct formed by zinc oxide and the well-known ruthenium dye N719. The wurtzite form of zinc oxide suffers from piezoelectricity and its energetic levels are very similar to those of the most used inorganic semiconductor employed in DSSCs, that is, TiO2 . We demonstrate that the synthesis of a ZnO@N719 nanoadduct does not affect the electronic communication between the inorganic semiconductor and the organic dye. The I-V characteristics in the dark and under illumination highlight a photoactivity of the ZnO@N719 active layer with values of Jsc , Voc and fill factor comparable to the data reported in the literature. When a mechanical strain is applied to the ZnO@N719 film, a piezopotential is recorded and it depends on the intensity of the applied pressure. According to the piezotronic effect, mechanical strain contributes to increase the open circuit voltage by about 14 %.

A porous collagen-based hydrogel scaffold was prepared in the presence of iron oxide nanoparticles (NPs) and was characterized by means of infrared spectroscopy and scanning electron microscopy. The hybrid scaffold was then loaded with fluorescein sodium salt as a model compound. The release of the hydrosoluble species was triggered and accurately controlled by the application of an external magnetic field, as monitored by fluorescence spectroscopy. The biocompatibility of the proposed matrix was also tested by the MTT assay performed on 3T3 cells. Cell viability was only slightly reduced when the cells were incubated in the presence of the collagen-NP hydrogel, compared to controls. The economicity of the chemical protocol used to obtain the paramagnetic scaffolds as well as their biocompatibility and the safety of the external trigger needed to induce the drug release suggest the proposed collagen paramagnetic matrices for a number of applications including tissue engeneering and drug delivery.

Amyloid supramolecular assemblies have found widespread exploitation as ordered nanomaterials in a range of applications from materials science to biotechnology. New strategies are, however, required for understanding and promoting mature fibril formation from simple monomer motifs through easy and scalable processes. Noncovalent interactions are key to forming and holding the amyloid structure together. On the other hand, the halogen bond has never been used purposefully to achieve control over amyloid self-assembly. Here we show that single atom replacement of hydrogen with iodine, a halogen-bond donor, in the human calcitonin-derived amyloidogenic fragment DFNKF results in a super-gelator peptide, which forms a strong and shape-persistent hydrogel at 30-fold lower concentration than the wild-type pentapeptide. This is remarkable for such a modest perturbation in structure. Iodination of aromatic amino acids may thus develop as a general strategy for the design of new hydrogels from unprotected peptides and without using organic solvents., Amyloid assemblies lie at the heart of many physiological functions, as well as being the cause of numerous diseases. Here, the authors subtly modify wild-type pentapeptides with halides, and discover that the new halogen bonding interactions have a remarkable influence on their physical properties.

New perylene monoimides, diimides and bis-diimides have been designed and synthetized. A detailed investigation of the synthesis of these compounds has also been performed in order to highlight the crucial factors for obtaining a specific class of molecules. Specifically, the attention has been focused on the synthesis of the intermediate perylene monoimides which are very useful precursors for many molecules difficult to obtain. Furthemore, two synthetic pathways have been developed for obtaining the bis-diimides variously substituted. These final compounds are predicted to mimic the excellent electron acceptor properties of fullerene derivatives and they can be used as building blocks to form 3D semiconducting materials.

A supramolecular adduct formed by the interaction among octadecylamine (ODA) and zinc oxide nanostructures was promoted. A stable dispersion of the ZnO@ODA adduct was obtained and characterized by means of thermogravimetric analysis and infrared and Raman spectroscopy. Then, the supramolecular adduct was spread at the air/water interface of a Langmuir trough. The presence of octadecylamine gave amphiphilic features to the ZnO@ODA adduct that was transferred from the air/water interface to solid substrates by Langmuir–Schaefer (LS) method. The transferred film was characterized by tunnel electron microscopy that highlighted rectangular well-shaped structures assembled by nanostructure of ZnO arranged in an ODA matrix. Piezoelectric feature of large LS film (1 cm2) was tested and a very promising response was observed as a consequence of the application of a pressure of 1 kPa.

A new and simple method is presented to fluorinate the surfaces of poorly reactive hydrophobic polymers in a more environmentally friendly way using the protein hydrophobin (HFBII) as a nanosized primer layer. In particular, HFBII, via electrostatic interactions, enables the otherwise inefficient binding of a phosphate-terminated perfluoropolyether onto polystyrene, polypropylene, and low-density polyethylene surfaces. The binding between HFBII and the perfluoropolyether depends significantly on the environmental pH, reaching the maximum stability at pH 4. Upon treatment, the polymeric surfaces mostly retain their hydrophobic character but also acquire remarkable oil repellency, which is not observed in the absence of the protein primer. The functionalization proceeds rapidly and spontaneously at room temperature in aqueous solutions without requiring energy-intensive procedures, such as plasma or irradiation treatments.

A totally green synthesis protocol has been adopted to obtain silver nanoaggregates capped by the natural compound (1E, 6E)-1,7-Bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5- diene), also known as curcumin. The synthesis process has been monitored by means of infrared, Raman, visible and fluorescence spectroscopies. Characterization confirms that curcumin reduces and caps the nanoparticles and such procedure allows its solubility in water and drastically increases the curcumin stability. Silver nanoparticles (AgNPs)/curcumin complex has been dispersed in a water solution containing a known nickel ion concentration. After three days a grey precipitate is observed and the nickel concentration in the solution is reduced of about 70%.

The use of organic materials in the realization of devices for the conversion of solar energy is a hot topic in chemistry, physics, and material science since many years. While the attention is strongly paid toward the synthesis and engineering of new molecules with adequate chemical and physical properties, such materials have to be transferred onto solid substrates, in order to construct functioning devices with high reproducibility and optimizing the performances. Then, deposition technique plays a paramount role in the realization of a photovoltaic device. Moreover, photoactive thin films are often carried out by multilayer stacks with a high spatial organization, and this observation prompted out many researchers to use layer-by-layer, Langmuir–Blodgett (LB), or Langmuir–Schaefer (LS) methods as deposition techniques for the fabrication of such devices. One of the most used class of substances for depositing LB or LS thin films is represented by the porphyrin derivatives whose filmability features can be improved by means of chemical functionalization or by the co-spreading of filmmaker molecules such as octadecylamine or arachidic acid. Furthermore, porphyrins show a very high light harvesting, and they are well-known electron donors, as it happens in the photosynthesis process. In this chapter, several examples of LB and LS film of porphyrin derivatives both used for the realization of photovoltaic devices and for studying the charge transfer processes have been reported.

Oil bodies (OBs) are micelle-like structures with an outer phospholipid monolayer embedding some specific proteins (oleosins) and surrounding a hydrophobic core of triacylglycerols (TAGs). Oleosins are alkaline hairpin-like proteins that are anchored into the OBs structure with their hydrophilic domains covering the surface. We performed surface pressure (?) and Brewster Angle Microscopy investigations of reconstituted OBs (ROBs) and of trypsin digested ROBs. The obtained ? vs time isotherms clearly show the formation of a surface layer. Upon ROBs suspension injection into the subphase, a clear-cut ? enhancement is recorded, followed by a long plateau region for ROBs suspensions more concentrated than 12.5. ?g/ml. The BAM analysis highlighted the presence of a dark background, ascribable to a 2D layer due to free components rearrangement and brilliant circular 3D domains, due to unaltered ROBs or small aggregates of ROBs. Increasing ROBs concentration, large domains appeared. We hypothesize that the presence of an excess of free TAGs in the 2D layer is crucial for the generation of such domains. We verified the generation of such typical structures, studying the behavior of a ROBs suspension (concentration of 12.5. ?g/ml) with two different approaches: after injection under a concentrated TAGs floating layers and after digestion with trypsin. These two procedures resulted in similar effects since proteinase digestion is like to induce the same morphology of a TAGs excess. © 2014 Elsevier B.V.