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An unusual self‐assembly pattern is observed for highly ordered 1500‐nm‐thick films of monodisperse 13‐nm‐sized colloidal PbSe quantum dots, originating from their faceted truncated cube‐like shape. Specifically, self‐assembled PbSe dots exhibited attachment to the substrate by <001> planes followed by an interconnection through the {001} facets in plan‐view and {110}/{111} facets in cross‐sectional‐view, thus forming a cubic superlattice. The thermoelectric properties of the PbSe superlattice thin films are investigated by means of frequency domain thermoreflectance, scanning thermal probe microscopy, and four‐probe measurements, and augmented by computational efforts. Thermal conductivity of the superlattice films is measured as low as 0.7 W m−1 K−1 at room temperature due to the developed nanostructure. The low values of electrical conductivity are attributed to the presence of insulating oleate capping ligands at the dots’ surface and the small contact area between the PbSe dots within the superlattice. Experimental efforts aiming at the removal of the oleate ligands are conducted by annealing or molten‐salt treatment, and in the latter case, yielded a promising improvement by two orders of magnitude in thermoelectric performance. The result indicates that the straightforward molten‐salt treatment is an interesting approach to derive thermoelectric dot superlattice thin films over a centimeter‐sized area. [ABSTRACT FROM AUTHOR]

Inspired by nature, intelligent self‐healing materials have recently been exploited also in the field of photovoltaics to mimic natural systems achieving self‐repairing. The past decade has witnessed perovskite solar cells (PSCs) skyrocketing to a certified power conversion efficiency of 26.1%. However, their intrinsic instability, when exposing to moisture, high temperature, and continuous illumination, hampers their commercial development for a long‐term use in ambient operating conditions. Therefore, the use of smart self‐healing materials, based on self‐assembling properties and dynamic interactions, empowers PSCs with self‐recovery abilities to reinforce their pivotal role as efficient photovoltaic devices and encourage their exploitation in the market. Herein, the current progress in self‐healing perovskite materials with a special focus on self‐recovery after moisture exposure or mechanical damage with the aim to provide a valuable insight for research on this topic to accelerate the PSC commercialization process is highlighted. [ABSTRACT FROM AUTHOR]

Diamond nanoparticles are an extremely promising class of carbon‐based nanomaterials. Because of their versatility, they have an interest in a large variety of applications, however, their use in the fabrication of enzyme mimics was not previously investigated. In this study, we realized hybrid systems based on guanidinium derivatives and diamond nanoparticles by simple adsorption of the organic material on their surface. The guanidinium derivatives chosen for this study are calix[4]arenes, blocked in the cone conformation via functionalization at the lower rim with alkyl chains, and decorated with guanidinium or arginine units at the upper rim. The corresponding monofunctional counterparts were also investigated as model compounds. These materials were characterized with different experimental techniques, i. e. thermogravimetric analysis, dynamic light scattering, ζ‐potential measurements and IR/Raman spectroscopy. Their catalytic properties in the cleavage of phosphodiesters were investigated by an in‐depth kinetic analysis. The whole experimental picture points to conclude that these compounds are stably adsorbed onto the nanodiamonds surface and are active in the transesterification reaction of the RNA model compound 2‐hydroxypropyl p‐nitrophenyl phosphate in water, with a notable advantage over their catalytic performances at the same concentration in solution. [ABSTRACT FROM AUTHOR]

Industrializing water electrolyzers demands better electrocatalysts, especially for the anodic oxygen evolution reaction (OER). The prevailing OER catalysts are Ir or Ru‐based nanomaterials, however, they still suffer from insufficient stability. An alternative yet considerably less explored approach is to upgrade Rh, a known stable but moderately active element for OER electrocatalysis, via rational structural engineering. Herein, a precise synthesis of assembled RhRuFe trimetallenes (RhRuFe TMs) with an average thickness of 1 nm for boosting overall water splitting catalysis is reported. Favorable mass transport and optimized electronic structure collectively render RhRuFe TMs with an improved OER activity of an overpotential of 330 mV to deliver 10 mA cm−2, which is significantly lower than the Rh/C control (by 601 mV) and reported Rh‐based OER electrocatalysts. In particular, the RhRuFe TMs‐based water splitting devices can achieve the current density of 10 mA cm−2 at a low voltage of 1.63 V, which is among the best in the Rh‐based bifunctional catalysts for electrolyzers. The addition of Fe in RhRuFe TMs can modulate the strain/electron distribution of the multi‐alloy, which regulates the binding energies of H* and OH* in hydrogen and oxygen evolution reactions for achieving the enhanced bifunctional OER and HER catalysis is further demonstrated. [ABSTRACT FROM AUTHOR]

It is found that the disordered growth of bottom perovskite film deteriorates the buried interface of perovskite solar cells (PSCs), so developing a new material to modify the buried interface for regulating the crystal growth and defect passivation is an effective approach for improving the photovoltaic performance of PSCs. Here, we developed a new ionic liquid crystal (ILC, 1‐Dodecyl‐3‐methylimidazolium tetrafluoroborate) as both crystal regulator and defect passivator to modify the buried interface of PSCs. The high lattice matching between this ILC and perovskite promotes preferential growth of perovskite film along [001] direction, while the oriented ILC with mesomorphic phase has a strong chemical interaction with perovskite to passivate the interface defect, as a result, the modified buried interface exhibits suppressed defects, improved band alignment, reduced nonradiative recombination losses, and enhanced charge extraction. The ILC‐modified PSC delivers a power conversion efficiency of 24.92 % and maintains 94 % of the original value after storage in ambient for 3000 h. [ABSTRACT FROM AUTHOR]

Self‐assembling of peptides is essential for a variety of biological and medical applications. However, it is challenging to investigate the self‐assembling properties of peptides within the complete sequence space due to the enormous sequence quantities. Here, it is demonstrated that a transformer‐based deep learning model is effective in predicting the aggregation propensity (AP) of peptide systems, even for decapeptide and mixed‐pentapeptide systems with over 10 trillion sequence quantities. Based on the predicted AP values, not only the aggregation laws for designing self‐assembling peptides are derived, but the transferability relation among the APs of pentapeptides, decapeptides, and mixed pentapeptides is also revealed, leading to discoveries of self‐assembling peptides by concatenating or mixing, as consolidated by experiments. This deep learning approach enables speedy, accurate, and thorough search and design of self‐assembling peptides within the complete sequence space of oligopeptides, advancing peptide science by inspiring new biological and medical applications. [ABSTRACT FROM AUTHOR]

Biomaterials with improved biological features can be obtained by conjugating glycans to nanostructured peptides. Creating peptide‐glycan chimeras requires superb chemoselectivity. We expedite access to such chimeras by merging peptide and glycan solid‐phase syntheses employing a bifunctional monosaccharide. The concept was explored in the context of the on‐resin generation of a model α(1→6)tetramannoside linked to peptides, lipids, steroids, and adamantane. Chimeras containing a β(1→6)tetraglucoside and self‐assembling peptides such as FF, FFKLVFF, and the amphiphile palmitoyl‐VVVAAAKKK were prepared in a fully automated manner. The robust synthetic protocol requires a single purification step to obtain overall yields of about 20 %. The β(1→6)tetraglucoside FFKLVFF chimera produces micelles rather than nanofibers formed by the peptide alone as judged by microscopy and circular dichroism. The peptide amphiphile‐glycan chimera forms a disperse fiber network, creating opportunities for new glycan‐based nanomaterials. [ABSTRACT FROM AUTHOR]

Demonstration of efficient polarization‐signal filtering induced by molecular orientation in organic heterostructures remains elusive. Herein, an epitaxial growth technology is developed for blue‐emissive horizontal p‐distyrylbenzene (DSB) nanosheet (NS) arrays on 9,10‐dicyanoanthracene (DCA)‐dominated (DCA)1‐x(DSB)x doped nanowire (NW) backbone via a facile stepwise solution‐processed method. It is shown that the DSB NS arrays generate blue amplified spontaneous emission (ASE), whereas the backbone of the (DCA)1‐x(DSB)x displays intense yellow emission. Surprisingly, the blue ASE can effectively propagate in (DCA)1‐x(DSB)x backbone immunity to DCA absorption and realize polarization filtering of output ASE. The mechanism of the orthogonal polarization between blue‐ASE from branches and absorption of DCA molecules in the backbone is responsible for the efficient transport of higher‐energy photons in narrow‐gap emitters. This molecular orientation‐induced polarized‐light transport can serve to control light propagation and function as polarization filter in a single heterostructure. The research provides an interesting example for the exploration of novel all‐optical switch devices in photonic circuits. [ABSTRACT FROM AUTHOR]

We aimed to determine the coacervation properties of high‐molecular‐weight (HMW) tissue‐derived elastin (TDE) and to examine the potential use of TDE particles as a cosmetic biomaterial. TDE solutions were filtered and divided into three fractions (1–3) according to the molecular weight of the elastin. The turbidity of fraction 2, which contained a large portion (58%) of HMW elastin polypeptides (>100 kDa), was measured under several pH values (3.0–11.0) and NaCl concentrations (0–1000 mM) to examine its coacervation ability. HMW TDE exhibited coacervation under the physiological conditions (temperature, pH, and NaCl concentration) of the skin surface. We performed inclusion and release experiments using three model chemicals with different molecular weights and measured the size and zeta potential of the fraction 3 particles to investigate the suitability of HMW elastin polypeptides. Fraction 3, which contained a larger portion (64%) of HMW elastin polypeptides, displayed a strong coacervation property at a phase transition temperature of 19.8 ± 0.1°C. The inclusion ratio of the model chemical Biebrich Scarlet (BS) with a molecular weight of <600 was approximately 92.1 ± 0.7%. The release profiles of BS from the particles linearly increased and reached a plateau after 15 days. Moreover, the average size of the particles with BS was 474.2 ± 24.6 nm. The low‐molecular‐weight (LMW) elastin peptides have moisturizing and whitening functions for the skin. We concluded that TDE, as a mixture of HMW polypeptides and LMW peptides, can potentially serve as a multifunctional and effective cosmetic biomaterial. [ABSTRACT FROM AUTHOR]

Short and ultra‐short peptides have been recently envisioned as excellent building blocks for the formulation of hydrogels with appealing properties. Due to its simplicity and capability to gel under physiological conditions, Fmoc‐FF (Nα‐fluorenylmethoxycarbonyl‐diphenylalanine), remains one of the most studied low molecular‐weight hydrogelators. Since its first identification in 2006, a plethora of its analogues were synthetized and investigated for the fabrication of novel supramolecular materials. Here we report a description of the Fmoc‐FF analogues in which the aromatic Fmoc group is replaced with other substituents. These analogues are distinguished into five different classes including derivatives: i) customized with solid phase peptide synthesis protecting groups; ii) containing non‐aromatic groups, iii) containing aromatic groups, iv) derivatized with metal complexes and v) containing stimuli‐responsive groups. The morphological, mechanical, and functional effects caused by this modification on the resulting material are also pointed out. [ABSTRACT FROM AUTHOR]

The first line of treatment for most solid tumors is surgical resection of the primary tumor with adequate negative margins. Incomplete tumor resections with positive margins account for over 75% of local recurrences and the development of distant metastases. In cases of oral cavity squamous cell carcinoma (OSCC), the rate of successful tumor removal with adequate margins is just 50–75%. Advanced real‐time imaging methods that improve the detection of tumor margins can help improve success rates,overall safety, and reduce the cost. Fluorescence imaging in the second near‐infrared (NIR‐II) window has the potential to revolutionize the field due to its high spatial resolution, low background signal, and deep tissue penetration properties, but NIR‐II dyes with adequate in vivo performance and safety profiles are scarce. A novel NIR‐II fluorophore, XW‐03‐66, with a fluorescence quantum yield (QY) of 6.0% in aqueous media is reported. XW‐03‐66 self‐assembles into nanoparticles (≈80 nm) and has a systemic circulation half‐life (t1/2) of 11.3 h. In mouse models of human papillomavirus (HPV)+ and HPV‐ OSCC, XW‐03‐66 outperformed indocyanine green (ICG), a clinically available NIR dye, and enabled intraoperative NIR‐II image‐guided resection of the tumor and adjacent draining lymph node with negative margins. In vitro and in vivo toxicity assessments revealed minimal safety concerns for in vivo applications. [ABSTRACT FROM AUTHOR]

Lacking high‐performance nonlinear optical (NLO) materials limits the applications to opto‐electronic devices. In this work, a strategy of self‐assembling driven by π‐π stacking is proposed to design high‐performance NLO materials. Here, the third‐order NLO responses of two carbon‐based fuller‐rylenes dimers (Fuller‐PMI and Fuller‐PDI) are theoretically studied. The results mainly highlight the following points: (1) these two dimers are in good thermodynamic and kinetic stability, and the interaction energies of Fuller‐PMI and Fuller‐PDI dimers have reached to −63.50 kcal/mol and −68.18 kcal/mol, respectively; (2) the ratios of the static second order hyperpolarizability (γiiiiFF, i∈{x, y, z}) between the dimer and the monomer are γxxxxFFdimerγxxxxFFmonomer = 5.5, γyyyyFFdimerγyyyyFFmonomer = 1.2 and γzzzzFFdimerγzzzzFFmonomer = 1.2 for Fuller‐PMI, γxxxxFFdimerγxxxxFFmonomer = 1.1, γyyyyFFdimerγyyyyFFmonomer =1.4 and γzzzzFFdimerγzzzzFFmonomer = 4.2 for Fuller‐PDI. These results demonstrate that the self‐assembling driven by π‐π stacking is an effective strategy for designing high‐performance NLO materials. [ABSTRACT FROM AUTHOR]

The calix[4]arene scaffold, blocked in the cone conformation through alkylation with long alkyl chains, and decorated at the upper rim with four guanidine or arginine units, effectively catalyzes the cleavage of the phosphodiester bond of DNA and RNA model compounds in water. An exhaustive kinetic investigation unequivocally points to the existence of spontaneous aggregation phenomena, driven by hydrophobic effect, occurring at different critical concentrations that depend on the identity of the compound. A pronounced superiority of the assembled structures compared with the monomers in solution was observed. Moreover, the catalytically active units, clustered on the macrocyclic tetrafunctional scaffold, were proved to efficiently cooperate in the catalytic mechanism and result in improved reaction rates compared to those of the monofunctional model compounds. The kinetic analysis is also integrated and corroborated with further experiments based on fluorescence spectroscopy and light scattering. The advantage of the supramolecular assemblies based on tetrafunctional calixarenes leads to believe that the active units can cooperate not only intramolecularly but also intermolecularly. The molecules in the aggregates can probably mold, flex and rearrange but, at the same time, keep an ordered structure that favors phosphodiester bond cleavage. This dynamic preorganization can allow the catalytic units to reach a better fitting with the substrates and perform a superior catalytic activity. [ABSTRACT FROM AUTHOR]

Achieving self‐assembling structures that exhibit emergent properties and functionalities is one of the holy grails in nanotechnology and holds great promise for a wide range of potential applications. Herein, a self‐assembled LuFeO3–(1/3)LuFe2O4–LuFeO3 heterostructure that consists of two model multiferroics, i.e., hexagonal LuFeO3 and rhombohedral LuFe2O4, is reported in single‐layer epitaxial LuFeO3 thin films. Atomic‐scale electron microscopy investigations reveal the spontaneous organization of ferroelectric polarization in each building block, which forms a series of polar configurations. Specifically, the charge and lattice of neighboring LuFeO3 and LuFe2O4 blocks are closely coupled with competing degrees of freedom. A combination of the quantitative analysis of atomically resolved images and spectroscopy with theoretical calculations determines how charge‐ordering‐induced polarization accommodates charge naturality across the interfaces to reduce the system energy and unravels the formation mechanism of this heterostructure. The results point to the possibilities of generation and control of multiferroic self‐assembled systems, which may provide a basis for engineering novel materials with emergent properties. [ABSTRACT FROM AUTHOR]

As a novel type of antibiotic alternative, peptide-based antibacterial drug shows potential application prospects attributable to their unique mechanism for lysing the membrane of pathogenic bacteria. However, peptide-based antibacterial drugs suffer from a series of problems, most notably their immature stability, which seriously hinders their application. In this study, self-assembling chimeric peptide nanoparticles (which offer excellent stability in the presence of proteases and salts) are constructed and applied to the treatment of bacterial infections. In vitro studies are used to demonstrate that peptide nanoparticles NPs1 and NPs2 offer broad-spectrum antibacterial activity and desirable biocompatibility, and they retain their antibacterial ability in physiological salt environments. Peptide nanoparticles NPs1 and NPs2 can resist degradation under high concentrations of proteases. In vivo studies illustrate that the toxicity caused by peptide nanoparticles NPs1 and NPs2 is negligible, and these nanoparticles can alleviate systemic bacterial infections in mice and piglets. The membrane permeation mechanism and interference with the cell cycle differ from that of antibiotics and mean that the nanoparticles are at a lower risk of inducing drug resistance. Collectively, these advances may accelerate the development of peptide-based antibacterial nanomaterials and can be applied to the construction of supramolecular nanomaterials. [ABSTRACT FROM AUTHOR]

Skeletal conditions represent a considerable challenge to health systems globally. Barriers to effective therapeutic development include a lack of accurate preclinical tissue and disease models. Most recently, work was attempted to present a novel whole organ approach to modeling human bone and cartilage tissues. These self‐assembling skeletal organoids mimic the cellular milieu and extracellular organization present in native tissues. Bone organoids demonstrated osteogenesis and micro vessel formation, and cartilage organoids showed evidence of cartilage development and maturation. Skeletal organoids derived from both bone and cartilage tissues yielded spontaneous polarization of their cartilaginous and bone components. Using these hybrid skeletal organoids, we successfully generated "mini joint" cultures, which we used to model inflammatory disease and test Adenosine (A2A) receptor agonists as a therapeutic agent. The work and respective results indicated that skeletal organoids can be an effective biological model for tissue development and disease as well as to test therapeutic agents. [ABSTRACT FROM AUTHOR]

Peptide‐based hydrogels, originated by multiscale self‐assembling phenomenon, have been proposed as multivalent tools in different technological areas. Structural studies and molecular dynamics simulations pointed out the capability of completely aromatic peptides to gelificate if hydrophilic and hydrophobic forces are opportunely balanced. Here, the effect produced by the introduction of a Cys residue in the heteroaromatic sequence of (FY)3 and in its PEGylated variant was evaluated. The physicochemical characterization indicates that both FYFCFYF and PEG8‐FYFCFYF are able to self‐assemble in supramolecular nanostructures whose basic cross‐β motif resembles the one detected in the ancestor (FY)3 assemblies. However, gelification occurs only for FYFCFYF at a concentration of 1.5 wt%. After cross‐linking of cysteine residues, the hydrogel undergoes to an improvement of the rigidity compared to the parent (FY)3 assemblies as suggested by the storage modulus (G') that increases from 970 to 3360 Pa. The mechanical properties of FYFCFYF are compatible with its potential application in bone tissue regeneration. Moreover, the avalaibility of a Cys residue in the middle of the peptide sequence could allow the hydrogel derivatization with targeting moieties or with biologically relevant molecules. [ABSTRACT FROM AUTHOR]

A "three‐components" supramolecular assembly has been fabricated by mixing 2, 2': 6', 2"‐terpyridine attached pillar[5]arene, cyano and triazole bearing alkyl chain and Zn2+ in solvent of CHCl3 and CH3CN. The driving forces for the assembly were believed to be host‐guest and metal chelating interactions as characterized by 1H NMR, UV‐vis and fluorescence spectra. The supramolecular organo‐gel formed upon the concentration of components amount to 1 M. The supramolecular displayed nitrobenzene based explosive sensing capability using picric acid, ortho‐nitrobenzene and phenol as samples. The assembly was most sensitive towards picric acid among the three analytes. The limit of detection for picric acid was determined to be 1.66 × 10−4 M. [ABSTRACT FROM AUTHOR]

Instilling segregated cationic and lipophilic domains with an angular disposition in a trehalose‐based trifaceted macrocyclic scaffold allows engineering patchy molecular nanoparticles leveraging directional interactions that emulate those controlling self‐assembling processes in viral capsids. The resulting trilobular amphiphilic derivatives, featuring a Mickey Mouse architecture, can electrostatically interact with plasmid DNA (pDNA) and further engage in hydrophobic contacts to promote condensation into transfectious nanocomplexes. Notably, the topology and internal structure of the cyclooligosaccharide/pDNA co‐assemblies can be molded by fine‐tuning the valency and characteristics of the cationic and lipophilic patches, which strongly impacts the transfection efficacy in vitro and in vivo. Outstanding organ selectivities can then be programmed with no need of incorporating a biorecognizable motif in the formulation. The results provide a versatile strategy for the construction of fully synthetic and perfectly monodisperse nonviral gene delivery systems uniquely suited for optimization schemes by making cyclooligosaccharide patchiness the focus. [ABSTRACT FROM AUTHOR]

A cost effective method to tailor the optical response of large‐area nanosheets of 2D materials is described. A reduced effective metalayer model is introduced to capture the key‐role of the out‐of‐plane component of the dielectric tensor. Such a model indicates that the optical extinction of 2D materials can be strongly altered by controlling the geometry at the local (i.e., subwavelength) scale. In particular, a giant linear optical dichroism at normal incidence is demonstrated, with major features around the excitonic peaks, that can be tailored by acting on the average curvature and slope of the nanosheets. The approach is experimentally demonstrated in few‐layer MoS2 grown by chemical vapor deposition on cm‐scale anisotropic nanopatterned substrates prepared by a self‐assembling technique, based on defocused ion beam sputtering. Major variations in the photoluminescence spectrum as a function of the average curvature and slope are also revealed. A full‐vectorial numerical study beyond the effective metalayer model and comprising strain effects induced by the geometry turns out to be consistent with such a complex scenario. The results demonstrate that the extrinsic geometrical engineering definitely opens viable way to tailor the optical properties and modulate bandgap of low dimensional materials. [ABSTRACT FROM AUTHOR]

The transport of confined micron‐sized particles plays an important role in a range of phenomena in biology, colloidal science, and solid‐state physics. Here, an easily implementable strategy that allows for the collective and monitored transport of magnetic colloidal particles along fluid–fluid interfaces is introduced. Adsorbed microparticles are carried on time‐dependent magnetic potentials, generated by dynamic self‐assembled lattices of different‐sized particles confined onto a parallel plane. In such binary system, the synchronized inversion of the precessing applied field allows for the ballistic and directional transport of the motile components along prescribed directions. The transportation mode can be tuned through the stoichiometry or the strength and orientation of the applied field. The described methodology can be used in the capture and manipulation of drugs or pollutants adsorbed on liquid surfaces, the segregation of colloidal mixtures or the assisted mixture of surface active molecules. [ABSTRACT FROM AUTHOR]

BACKGROUND Bacterial cells can biosynthesize palladium nanoparticles (Pd NPs) and utilize those in situ assembled nanoparticles for synergistic bio‐abiotic catalysis, which is promising for pollutant remediation. However, such synergistic catalysis is restricted due to the low cell viability and inefficient palladium immobilization. RESULTS: In this study, conductive and two‐dimensional reduced graphene oxide (rGO) was explored for nanocoating of Shewanella oneidensis cells and the construction of a self‐assembled Shewanella@rGO bionanohybrid. Impressively, after in situ biosynthesis of Pd NPs on the Shewanella@rGO bionanohybrid, a Shewanella@rGO@Pd bionanohybrid was assembled, which showed about 10 times higher cell viability and 2.4 times more immobilized palladium content than the bionanohybrid without rGO. More importantly, the improved cell viability and enhanced Pd immobilization synergistically promoted Cr(VI) removal using the Shewanella@rGO@Pd bionanohybrid, which was 10 times that of native cells and five times that of the bionanohybrid without rGO. CONCLUSIONS: This work provides a promising strategy for biosynthesis and in situ assembly of Pd NPs with living bacterial cells, which is promising for synergistic bio‐abiotic removal of Cr(VI) and should extend the application of Pd NPs in pollutant remediation. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The self‐organization process of polysaccharide alginate with different cationic surfactants at the water‐air interface was investigated over a wide concentration regime. The changes of surface properties determined by surface tension measurements, surface rheology, and X‐ray reflectivity are correlated with changes of bulk properties measured by turbidity, light scattering, and zeta potential measurements. We demonstrate that the interactions between the alginate and cationic surfactants result in significant changes of bulk and interfacial properties. The results of surface shear experiments point to the existence of highly viscoelastic interfacial films. In combination with X‐ray reflectivity, we demonstrate that these rheological features are related to polymer‐surfactant associations at the interface. In the regime of high surfactant concentrations, we observed the existence of multilayer structures. [ABSTRACT FROM AUTHOR]

Polylactide (PLA) is a biodegradable polyester recognized for its potential use as a biomedical material. Poly(ethylene oxide) (PEO) and copolymers based on PEO and poly(propylene oxide) (PPO) are biocompatible polyethers widely applied in the biomedical field, particularly as macromolecular nonionic surfactants. In this work, PLA blocks were attached to the PEO and to the PEO and PPO‐based triblock copolymer PEO–PPO–PEO, through ring‐opening polymerization of racemic lactide (rac‐LA) to obtain the amphiphilic triblock PLA–PEO–PLA and pentablock PLA–PEO–PPO–PEO–PLA copolymers containing hydrophilic/hydrophobic blocks with variable block mass ratios. The copolymers were evaluated for chemical composition, molar mass, and thermal properties, and they were used to prepare self‐assemble aggregates in water from tetrahydrofuran polymer solutions. The combination of scattering light experiments and microscopy techniques revealed the spherical morphology of the aggregates with diameters around 180–200 nm, which comprises a hydrophobic PLA core and a hydrophilic polyether shell. The aggregates are nontoxic to human cervical cancer cell line — HeLa cells, as determined by MTS assay, and the aggregates are potential candidates to be applied in the encapsulation of hydrophobic compounds. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2203–2213 Amphiphilic PLA–PEO–PLA and PLA–PEO–PPO–PEO–PLA copolymers containing the hydrophilic polyethers middle‐blocks and the hydrophobic amorphous PLA end‐blocks were used to prepare self‐assembled aggregates in water from tetrahydrofuran solutions. The combination of scattering light experiments and microscopy techniques revealed the spherical core–shell morphology of the aggregates with diameters around 180–200 nm. The aggregates are nontoxic and therefore potential candidates to be applied in the encapsulation of hydrophobic biologic compounds. [ABSTRACT FROM AUTHOR]

Abstract: Hybrid copolymers constituted by short l‐phenylalanine (Phe) blocks (i.e., Phen with n ranging from 2 to 25) and l‐lactide blocks of different length are synthesized and characterized. The diblock structure is obtained by ring opening polymerization of lactide using a Phe‐oligopeptide as macroinitiator. The length of the poly( l‐lactide) (PLLA) block is controlled through the [lactide]/[macroinitiator] ratio. Morphologic studies of such hybrid copolymers indicate that the assembly of PLLA can be controlled by introducing short Phe blocks. Spherulites with both positive and negative birefringence are achieved in melt crystallization as a consequence of different lamellar distributions. Instead, a high variety of structures are detected in solution‐crystallized samples. Specifically, lozenge single crystals, flower‐like crystals, fibrillar structures, compact spheres, ringed sperulites, dendritic structures, microfibers, and braid‐like microstructures are observed. Some of the detected morphologies are characteristic of self‐assembled Phe‐oligopeptides, suggesting that Phe‐blocks play a crucial role in the self‐assembly properties. [ABSTRACT FROM AUTHOR]

Abstract: The self‐assembly of specific polymers into well‐defined nanoparticles (NPs) is of great interest to the pharmaceutical industry as the resultant materials can act as drug delivery vehicles. In this work, a high‐throughput method to screen the ability of polymers to self‐assemble into NPs using a picoliter inkjet printer is presented. By dispensing polymer solutions in dimethyl sulfoxide (DMSO) from the printer into the wells of a 96‐well plate, containing water as an antisolvent, 50 suspensions are screened for nanoparticle formation rapidly using only nanoliters to microliters. A variety of polymer classes are used and in situ characterization of the submicroliter nanosuspensions shows that the particle size distributions match those of nanoparticles made from bulk suspensions. Dispensing organic polymer solutions into well plates via the printer is thus shown to be a reproducible and fast method for screening nanoparticle formation which uses two to three orders of magnitude less material than conventional techniques. Finally, a pilot study for a high‐throughput pipeline of nanoparticle production, physical property characterization, and cytocompatibility demonstrates the feasibility of the printing approach for screening of nanodrug delivery formulations. Nanoparticles are produced in the well plates, characterized for size and evaluated for effects on metabolic activity of lung cancer cells. [ABSTRACT FROM AUTHOR]

Abstract: Ultrathin films of CdSe nannocrystals (CdSe‐NCs) modified with glycosilated molecules have shown interesting electrochemical properties which lead to the detection of lectin Jacalin. [ABSTRACT FROM AUTHOR]

Hybrid structures of InGaAs/InAlAs two‐dimensional quantum well superlattices and self‐assembled InAs quantum dots (QD) are fabricated on an InP(311)B substrate by the digital embedding method. Samples, in which the period of the superlattice is changed, are evaluated by atomic force microscope and polarized photoluminescence (PL). The intensity of PL polarized in the [‐233] direction is found to be higher than that in the [01–1] direction, which is affected by the structural anisotropy of InAs QDs and crystal anisotropy of the (311) surface. The polarization degree can be controlled by changing the period of the superlattice. These results indicate that the thickness of the InAlAs barrier of the superlattice plays an important role for controlling optical properties of InAs QDs embedded in superlattices. [ABSTRACT FROM AUTHOR]

ABSTRACT Hydrophobins are amphiphilic fungal proteins endowed with peculiar characteristics, such as a high surface activity and an interface triggered self-assembly. Several applications of these proteins have been proposed in the food, cosmetics and biomedical fields. Moreover, their use as proteinaceous coatings can be effective for materials and nanomaterials applications. The discovery of novel hydrophobins with diverse properties may be advantageous from both the scientific and industrial points of view. Stressful environmental conditions of fungal growth may induce the production of proteins with peculiar features. Two Class I hydrophobins from fungi isolated from marine environment have been recently purified. Herein, their propensity to aggregate forming nanometric fibrillar structures has been compared, using different techniques, such as circular dichroism, dynamic light scattering and Thioflavin T fluorescence assay. Furthermore, TEM and AFM images indicate that the interaction of these proteins with specific surfaces, are crucial in the formation of amyloid fibrils and in the assembly morphologies. These self-assembling proteins show promising properties as bio-coating for different materials via a green process. Biotechnol. Bioeng. 2017;114: 2173-2186. © 2017 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Chitosan (CHI) is a versatile biological material that is well known for its hemostatic properties. This preliminary study evaluated several self-assembling hydrophobically modified chitosan (HM-CHI) sponges to determine their efficacy on . Fourier transform infrared (FT-IR) spectroscopy was used to determine the successful graft of dodecyl groups onto the nitrogen atoms of CHI molecules. A platelet aggregation assay revealed that HM-CHI accelerated the platelet aggregation rate. Fluorescence spectroscopy showed that the HM-CHI changed the structure of fibrinogen in blood. Activated partial thromboplastin time, prothrombin time, fibrinogen time, and thromboelastographic assays were used to explore the effect of HM-CHI on the autologous blood coagulation pathway. Finally, a hemostatic sponge was made with HM-CHI and freeze-dried zeolite composite film and was applied to the rat femoral artery model. A time of 86 ± 5 sec was achieved, which was significantly better than the one composed with pure CHI. The experimental results of the HM-CHI hemostatic materials are inspiring and will encourage the research and development of such materials. HM-CHI may be a strong candidate as a safe and effective hemostatic material. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Telechelic PEG-polymers end-capped by diphenylalanine (FF) motives and containing a DOTA-Gd complex, bound on a lysine side chain at the centre of peptide moiety, are studied for their assembling properties and for the relaxometric behavior. The observed variations in terms of relaxivity are correlated to the assembling properties of the aggregates by using several techniques: fluorescence, Circular Dichroism (CD) and Fourier Transform Infrared (FTIR) for aggregation tendency and secondary structure determination; Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) for morphological definition. Self-aggregation in water solution of the peptide conjugates, due to interaction of the phenylalanine frameworks, starts at concentration around 1 mg/ml with a first evidence of the coexistence of fibrillary networks and hydrogels at 10 mg/ml. Definitive presence of well-structured fibrillary networks, dominated by an antiparallel β-sheet arrangement, occurs at 50 mg/ml. At the latter concentration relaxivity values measured at 20 MHz and 298 K, are around 11 mM−1 s−1, in line with a possible use of the these aggregates as MRI contrast agents. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Formation and assembling of CdS nanocrystals (NC) on highly-ordered pyrolytic graphite (HOPG) and on oxidized silicon substrates have been investigated by atomic force microscopy (AFM) and scanning tunneling microscopy (STM). NC were initially formed within a Langmuir-Blodgett (LB) matrix of cadmium behenate. The LB matrix was then removed by annealing in an ammonia atmosphere. It is shown that the NC self-assembling is mainly determined by the LB matrix wetting properties. In case of wettable HOPG substrate homogeneous matrix evaporation occurs that leads to coarsening of the NC arrays as the main self-assembly process. Otherwise, NC prepared on non-wettable SiO2-Si substrate demonstrate arrays formation determined by the LB matrix dewetting process. For the both cases, the influence of kinetic limitations connected with matrix evaporation rate on the self-assembly process is observed. (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Semiconductors with isoelectronic centers are actively studied to fabricate arrays of identical single photon emitters. Self-assembling of 4N10In and 1N4In clusters in GaAs-rich InxGa1-xNyAs1-y is represented. All or almost all In atoms are in 4N10In clusters from 0 to 800 °C in InxGa1-xNyAs1-y with x = 1×10-4, y = 1×10-4 and x = 1×10-5, y = 1×10-5. All or almost all nitrogen atoms are in 1N4In clusters if x = 0.01, y = 1×10-4 and x = 1×10-3, y = 1×10-6. There are both types of clusters in alloys with x = 5×10-5, y = 5×10-7; x = 2×10-4, y = 2×10-6; x = 1×10-4, y = 1×10-5 and x = 2×10-3, y = 2×10-4 and portions of nitrogen atoms in clusters depend on the composition and temperature. Thus, InxGa1-xNyAs1-y are promising semiconductors to obtain arrays of identical isoelectronic clusters with the desirable density. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The discovery of stereocomplexation, secondary interaction between enantiomeric poly( l-lactide) ( PLLA) and poly( d-lactide) ( PDLA) provides a method for the creation of novel biomaterials with distinctive chemical and physical stability. Stereocomplexation opens a new way for the preparation of diverse micro- and nanostructures such as uniform microspheres, hollow particles, micelles, nanocrystals, nanofibres, nanotubes and polymerosomes. Herein, we describe the design of stereocomplex assemblies for specific applications and methods for their preparation. This review focuses primarily on the use of stereocomplex assemblies in biomedical applications due to the improved stability and physicochemical properties in comparison to enantiomeric polylactides. To make the polylactide stereocomplexes soluble in water and, as a consequence, to improve compatibility with the human body, various amphiphilic copolymers with PLLA and PDLA enantiomeric segments can be prepared. Stereocomplexation can facilitate their self-assembly into micro- and nanoparticles, stabilize the particle size and morphology and can also have an influence on the in vivo degradation rate and cytotoxicity of these materials. Stimuli-responsiveness in stereocomplex assemblies can be achieved by copolymerization of lactide with, for example, thermoresponsive N-isopropylacrylamide or amino acids with pH-sensitive pendant groups. Stereocomplex micro- and nanoparticles are used for encapsulation of various bioactive compounds: anticancer drugs, antibiotics and proteins. Finally, examples of materials in which high thermal and mechanical stabilities delivered as a result of stereocomplexation play a crucial role, i.e. hydrogels, nanofibres, microcellular foams and artificial skin, are described. The preparation of biomaterials and biomedical systems based on polylactide stereocomplex assemblies opens new opportunities in this field. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Class I hydrophobin Vmh2, a peculiar surface active and versatile fungal protein, is known to self-assemble into chemically stable amphiphilic films, to be able to change wettability of surfaces, and to strongly adsorb other proteins. Herein, a fast, highly homogeneous and efficient glass functionalization by spontaneous self-assembling of Vmh2 at liquid-solid interfaces is achieved (in 2 min). The Vmh2-coated glass slides are proven to immobilize not only proteins but also nanomaterials such as graphene oxide (GO) and quantum dots (QDs). As models, bovine serum albumin labeled with Alexa 555 fluorophore, anti-immunoglobulin G antibodies, and cadmium telluride QDs are patterned in a microarray fashion in order to demonstrate functionality, reproducibility, and versatility of the proposed substrate. Additionally, a GO layer is effectively and homogeneously self-assembled onto the studied functionalized surface. This approach offers a quick and simple alternative to immobilize nanomaterials and proteins, which is appealing for new bioanalytical and nanobioenabled applications. [ABSTRACT FROM AUTHOR]

Due to their potential biomedical applications, protein-based hydrogels have attracted considerable interest. Although various methods have been developed to engineer self-assembling, physically-crosslinked protein hydrogels, exploring novel driving forces to engineer such hydrogels remains challenging. Protein fragment reconstitution, also known as fragment complementation, is a self-assembling mechanism by which protein fragments can reconstitute the folded conformation of the native protein when split into two halves. Although it has been used in biophysical studies and bioassays, fragment reconstitution has not been explored for hydrogel construction. Using a small protein GL5 as a model, which is capable of fragment reconstitution to reconstitute the folded GL5 spontaneously when split into two halves, GN and GC, we demonstrate that protein fragment reconstitution is a novel driving force for engineering self-assembling reversible protein hydrogels. Fragment reconstitution between GN and GC crosslinks GN and GC-containing proteins into self-assembling reversible protein hydrogels. These novel hydrogels show temperature-dependent reversible sol-gel transition, and excellent property against erosion in water. Since many proteins can undergo fragment reconstitution, we anticipate that such fragment reconstitution may offer a general driving force for engineering protein hydrogels from a variety of proteins, and thus significantly expanding the 'toolbox' currently available in the field of biomaterials. [ABSTRACT FROM AUTHOR]

New homoditopic bis-calix[4]arene-carbazole conjugates, armed with hydrophilic carboxylic acid functions at their lower rims, are disclosed. Evidence for their self-association in solution was gathered from solvatochromic and thermochromic studies, as well as from gel-permeation chromatography analysis. Their ability to function as highly sensitive sensors toward polar electron-deficient aromatic compounds is demonstrated. [ABSTRACT FROM AUTHOR]

Biological interfacing of graphene has become crucial to improve its biocompatibility, dispersability, and selectivity. However, biofunctionalization of graphene without yielding defects in its sp2-carbon lattice is a major challenge. Here, a process is set out for biofunctionalized defect-free graphene synthesis through the liquid phase ultrasonic exfoliation of raw graphitic material assisted by the self-assembling fungal hydrophobin Vmh2. This protein (extracted from the edible fungus Pleurotus ostreatus) is endowed with peculiar physicochemical properties, exceptional stability, and versatility. The unique properties of Vmh2 and, above all, its superior hydrophobicity, and stability allow to obtain a highly concentrated (≈440-510 μg mL−1) and stable exfoliated material ( ζ-potential, +40/+70 mV). In addition controlled centrifugation enables the selection of biofunctionalized few-layer defect-free micrographene flakes, as assessed by Raman spectroscopy, atomic force microscopy, scanning electron microscopy, and electrophoretic mobility. This biofunctionalized product represents a high value added material for the emerging applications of graphene in the biotechnological field such as sensing, nanomedicine, and bioelectronics technologies. [ABSTRACT FROM AUTHOR]

Bioactive and biocompatible conjugated linoleic acid (CLA) has been only considered as a food or medicine ingredient due to its rare natural occurrence. In this work, the surface activities and pH-induced self-assembling behaviors of the semi-synthetic CLA molecules into micelles or vesicles were systematically investigated. First, the self-assembling of CLA was studied in detail, and it was found that aside from temperature and ionic strength, pH is the prominent factor affecting the self-assembling of CLA. Moreover, stable CLA ufasomes (unsaturated fatty acid liposomes) in uniform size were obtained by self-crosslinking of the CLA ufasomes, and the morphologies of the crosslinked CLA assemblies were recorded by transmission electron microscopy, which made known the pH-induced formation of the CLA ufasomes or the CLA micelles. The crosslinked CLA assemblies presented improved properties such as a higher calcium stability, a lower lime soap dispersing requirement and a better solubilization ability than that of the CLA molecules themselves or the pre-crosslinked linoleic acids. These investigations could be helpful for comprehensively understanding effects of environment factors on self-assembling behaviors of conjugated fatty acids and responsive polymerization of polymerizable surfactants. [ABSTRACT FROM AUTHOR]

Dendritic amphiphiles as novel building blocks are very important for self-assembling in the supramolecular chemistry area. In this work, a carbosilane dendrimer with hexamethylene as the branching unit (G1) was first synthesized as a hydrophobic core and then linked with poly(ethylene glycol) (PEG) units as the periphery by a hydrosilylation reaction to prepare an amphiphilic dendrimer (G1-PEG) with a yield of 27%. The aggregationbehavior of G1-PEG inwaterwas studied with surface tension, dynamic light scattering and transmission electron microscopy methods. The surface tension data showed that the critical aggregation concentration of such dendrimers inwater is approximately 0.75 g L-1. The results of dynamic light scattering and transmission electron microscopy indicated that the aggregate size of G1-PEG dendrimers in water is related to the concentration. Small micelles of about 10 nmwere found at high concentration, large vesicles of about 100 nm were observed at low concentration, and a mixture of micelles and vesicles was found at middle concentrations. The encapsulation of G1-PEG to a fluorescence probe verified the existence of a hydrophobic microenvironment in the aggregates at high concentrations of the amphiphilic dendrimer. [ABSTRACT FROM AUTHOR]

Gemini surfactants ( GS) are presently receiving substantial attention due to their special self-assembling properties and unique interfacial activity. This comprehensive review is focused on positively charged heterocyclic GS, presenting their major synthetic access routes and examining the impact of structural elements on physicochemical and aggregation properties of this class of amphiphiles. Interaction of geminis surfactants with cells and their biological properties as novel transfection agents are emphasized through a detailed structure-activity relationship analysis. Throughout the review we have also presented the properties of selected ammonium GS, simple surfactants and lipid congeners, in order to emphasize the advantages conferred by using heterocyclic polar heads in GS design. [ABSTRACT FROM AUTHOR]

The self-assembling behavior of 1-tetradecylphosphonic acid (TDPA) molecules on the surfaces of 2024 aluminum alloys was studied with an emphasis on the different micro-structural regions of the alloy surface, specially the alloy matrix and the two main types of intermetallic particles, as well as how the adsorption was effected by changes in water content of the self-assembly solution. Surface characterization was undertaken with contact angle measurement, scanning electron microscopy and Auger electron spectroscopy (AES). The packing density of TDPA film on the alloy surface increased with the increasing water content of the self-assembly solution. It seemed that the micro-distribution of TDPA molecules was related to copper amount and the region with a higher surface copper concentration had a lower packing density of TDPA. Some pits were formed in the acidic self-assembly solutions and the exposed surfaces of the pits can quickly adsorb TDPA molecules with compactness comparative to the matrix surface. Different adsorption models of TDPA corresponding to different water content of the self-assembly solution were suggested based on the analysis of AES depth sputtering data. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A noble-metal-free system for photochemical hydrogen production is described, based on ascorbic acid as sacrificial donor, aluminium pyridyl porphyrin as photosensitizer, and cobaloxime as catalyst. Although the aluminium porphyrin platform has docking sites for both the sacrificial donor and the catalyst, the resulting associated species are essentially inactive because of fast unimolecular reversible electron-transfer quenching. Rather, the photochemically active species is the fraction of sensitizer present, in the aqueous/organic solvent used for hydrogen evolution, as free species. As shown by nanosecond laser flash photolysis experiments, its long-lived triplet state reacts bimolecularly with the ascorbate donor, and the reduced sensitizer thus formed, subsequently reacts with the cobaloxime catalyst, thereby triggering the hydrogen evolution process. The performance is good, particularly in terms of turnover frequencies (TOF=10.8 or 3.6 min−1, relative to the sensitizer or the catalyst, respectively) and the quantum yield ( Φ=4.6 %, that is, 9.2 % of maximum possible value). At high sacrificial donor concentration, the maximum turnover number (TON=352 or 117, relative to the sensitizer or the catalyst, respectively) is eventually limited by hydrogenation of both sensitizer (chlorin formation) and catalyst. [ABSTRACT FROM AUTHOR]

The synthesis of asymmetric spherical nanoparticles has attracted great interest because their anisotropic structure can be used as unique building blocks for constructing advanced materials. In this article, we report the formation of hemispherical or truncated polystyrene/nanosaponite composite particles via one-pot miniemulsion polymerization. It was found that the morphology of final composite latex particles strongly depends on the size of the nanoclay and its surface properties. Hemisphere or truncated sphere is the dominant morphology if the size of the nanoclay is larger than 100 nm. With the increase of the nanoclay content (up to 30 wt %), the fraction of hemispherical or truncated polystyrene/nanosaponite composite latex particles increased accordingly. The formation of hemispherical particles is possibly attributed to either the asymmetric growth of polymer chains on one side of the hydrophobically modified clay or the mechanical peeling-off of large spherical particles between polymer and saponite. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

We show that thymine self-assembles into an ordered structure when adsorbed at a Au(110)/liquid interface. Reflection anisotropy spectroscopy (RAS) shows that as found for cytosine and adenine the adsorbed thymine molecules are oriented essentially vertically on the Au(110) surface with the molecule aligned along one of the principal axes of the Au(110) surface. Simulations of the RA spectra to an empirical model indicates that as found for adsorbed cytosine and adenine, thymine is aligned along the [ $1{\bar {1}}0$] direction on the Au(110) surface. [ABSTRACT FROM AUTHOR]

In this study, the synthesis of thin films of Mg phosphorus doped tungsten bronzes (MgPTB; MgHPW12O40·29H2O) by the self-assembly of nano-structured particles of MgPTB obtained using the ultrasonic spray pyrolysis method was investigated. As the precursor, MgPTB, prepared by the ionic exchange method, was used. Nano-structured particles of MgPTB were obtained using the ultrasonic spray pyrolysis method. The nano-structure of the particles used as the building blocks in the MgPTB thin film were investigated experimentally and theoretically, applying the model given in this article. The obtained data for the mean particle size and their size distribution show a high degree of agreement. These previously tailored particles used for the preparation of thin films during the next synthesis step, by their self-assembly over slow deposition on a silica glass substrate, show how it is possible to create thin MgPTB films under advance projected conditions of the applied physical fields with a fully determined nanostructure of their building block particles, with a relatively small roughness and unique physical properties. [ABSTRACT FROM AUTHOR]

1. Aggregation of individuals, a basic behaviour in social species, plays an essential role in many aspects of animal life (reproduction, defence, and alimentation). Understanding how this phenomenon is modulated is important to comprehend the social organisation of the group. 2. In social insects, aggregation is influenced by environmental (e.g. the light level) and social (e.g. polyethism in monomorphic ants) factors. Ants display a great variation of biological characteristics (e.g. queen number, polymorphism, division of labour, etc.) that are likely to influence the level of inter-attraction and so the aggregation. 3. The present research focused on one biological characteristic: the morphological castes (minors, majors), testing the hypothesis that minors will aggregate more than majors due to their greater need to fight against the loss of heat and to increase their self-protection. 4. Aggregation experiments were conducted on two highly polymorphic species, Atta sexdens rubropilosa and Solenopsis interrupta, using the two extreme morphological castes (majors and minors). 5. All castes exhibited a low level of aggregation: 40–50% of workers assembled for both species, the biggest cluster involving 20% of the total population. The lack of difference between morphological castes in the aggregation shows the weak influence of polymorphism on the interactions between ants. 6. It is concluded that the main factor modulating the aggregation behaviour is polyethism, i.e. the division of labour associated with the presence of an outside-the-nest experience: workers that only take care of the brood, without outside world experience (brood-tenders) assembling more than foraging workers (foragers). [ABSTRACT FROM AUTHOR]

Magnetic Microparticles: Collective Transport of Magnetic Microparticles at a Fluid Interface through Dynamic Self-Assembled Lattices (Adv. Funct. Keywords: collective transport; colloidal monolayer; fluid interface; self-assembling EN collective transport colloidal monolayer fluid interface self-assembling 1 1 1 12/10/20 20201208 NES 201208 In article number 2002206, Fernando Martínez-Pedrero, Carles Calero, and co-workers present an easily implementable strategy wherein small microparticles adsorbed at a fluid interface are transported through a lattice of larger spheres, in a practically deterministic motion, by periodically inverting the vertical component of a precessing field. Collective transport, colloidal monolayer, fluid interface, self-assembling. [Extracted from the article]

Cell‐selective targeting is expected to enhance effectiveness and minimize side effects of cytotoxic agents. Functionalization of drugs or drug nanoconjugates with specific cell ligands allows receptor‐mediated selective cell delivery. However, it is unclear whether the incorporation of an efficient ligand into a drug vehicle is sufficient to ensure proper biodistribution upon systemic administration, and also at which extent biophysical properties of the vehicle may contribute to the accumulation in target tissues during active targeting. To approach this issue, structural robustness of self‐assembling, protein‐only nanoparticles targeted to the tumoral marker CXCR4 is compromised by reducing the number of histidine residues (from six to five) in a histidine‐based architectonic tag. Thus, the structure of the resulting nanoparticles, but not of building blocks, is weakened. Upon intravenous injection in animal models of human CXCR4+ colorectal cancer, the administered material loses the ability to accumulate in tumor tissue, where it is only transiently found. It instead deposits in kidney and liver. Therefore, precise cell‐targeted delivery requires not only the incorporation of a proper ligand that promotes receptor‐mediated internalization, but also, unexpectedly, its maintenance of a stable multimeric nanostructure that ensures high ligand exposure and long residence time in tumor tissue. [ABSTRACT FROM AUTHOR]

Block copolymer (BCP) lithography is one of the most technologically intriguing and scientifically interesting strategies for achieving nanometer‐sized features. This method usually exploits toluene as solvent for the deposition of BCPs in all the processing steps. However, this chemical has some technical disadvantages, such as high toxicity and hygroscopicity. The first aspect can limit its use on the industrial scale because of the protocols on the environmental and operator risks, while the second causes aging effects that can alter the results. In order to overcome these intrinsic limitations, a BCP self‐assembly (BCP‐SA) strategy is presented by using alternative deposition solvents in place of toluene. A preliminary study, based on the physical characteristics, such as volatility, polarity, and hygroscopicity, is carried out to explore two new alternative solvents, ethyl acetate and tetrahydrofuran. The effects on the BCP‐SA due to the new solvents are studied by SEM analysis supported by suitable software for the images elaboration. The results achieved show very promising outcomes for the polymer solutions obtained with ethyl acetate, in terms of uniformity of geometrical features, ordered areas extension, and homogeneity of the pattern obtained, making this chemical a good alternative to toluene. [ABSTRACT FROM AUTHOR]