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The durability of concrete structures can be enhanced in a convenient and permanent manner through the surface protection of cementitious materials with composite polymer coatings. However, polymer coatings are susceptible to various mechanical and physical deterioration in complex and variable environments. In this paper, the theory of polymer microstructure regulation was employed to improve the sustainability of the protective performance of composite coatings. The self-assembled core-shell structure regulated by amphiphilic Janus nanoparticles is employed to modify the tunable polystyrene acrylate-polysiloxane self-healing coatings. The results demonstrate that the adhesion strength of the prepared self-assembled coating reached 3.7 MPa, which is sufficient to resist the damage to the microstructure of cementitious materials caused by physical erosion, seepage, and ionic corrosion. The self-healing coating, regulated by Janus particles, exhibited a residual creep of only 57.03% and a maximum loss angle tangent of 0.381. Furthermore, the material exhibited a superior shape memory function due to the presence of strong hydrogen bonding. The regulated self-healing coating repaired the polymer structural damage under mechanical and thermal deformation by bridging and filling effects. The coating demonstrated a tensile strength recovery of up to 71.23% in a wetted state, accompanied by a rapid restoration of its electrochemical properties and corrosion resistance. Furthermore, the self-healing emulsion penetrates the substrate defects and forms numerous polymer crystalline particles that effectively fill the microcracks.

Superlattices of nanoparticles are generally produced based on solution chemistry processes. In this paper, we demonstrate that self-assembled monolayer structures of nanoparticles with superlattice periodicities can also be produced on template-free surfaces in the gas-phase cluster beam deposition process. It is found that the packing of Fe nanoparticles corresponds to an average of two-dimensional densely packed lattice with a hexagonal summary. By controlling the nanoparticle coverage, the two-dimensional densely packed monolayer morphology can spread to the whole substrate surface being deposited. A formation mechanism of the ordered monolayers is proposed. The densely packed morphologies are formed by the balance between the diffusion rate of the nanoparticles and their filling speed on the substrate surface determined by the deposition rate, and the ordering of the nanoparticle arrays is driven by the inter-particle attractive interactions. The model is strongly supported by a series of carefully designed cluster deposition experiments. [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]

Chronic wounds represent a major health burden and drain on medical system. Efficient wound repair is only possible if the dressing materials target simultaneously multiple factors involved in wound chronicity, such as deleterious proteolytic and oxidative enzymes and high bacterial load. Here we develop multifunctional hydrogels for chronic wound management through self-assembling of thiolated hyaluronic acid (HA-SH) and bioactive silver-lignin nanoparticles (Ag@Lig NPs). Dynamic and reversible interactions between the polymer and Ag@Lig NPs yield hybrid nanocomposite hydrogels with shear-thinning and self-healing properties, coupled to zero-order kinetics release of antimicrobial silver in response to infection-related hyalurodinase. The hydrogels inhibit the major enzymes myeloperoxidase and matrix metalloproteinases responsible for wound chronicity in a patient's wound exudate. Furthermore, the lignin-capped AgNPs provide the hydrogel with antioxidant properties and strong antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa. The nanocomposite hydrogels are not toxic to human keratinocytes after 7 days of direct contact. Complete tissue remodeling and restoration of skin integrity is demonstrated in vivo in a diabetic mouse model. Hematological analysis reveals lack of wound inflammation due to bacterial infection or toxicity, confirming the potential of HA-SH/Ag@Lig NPs hydrogels for chronic wound management. Multifunctional hydrogels are promising materials to promote healing of complex wounds. Herein, we report simple and versatile route to prepare biocompatible and multifunctional self-assembled hydrogels for efficient chronic wound treatment utilizing polymer-nanoparticle interactions. Hybrid silver-lignin nanoparticles (Ag@Lig NPs) played both: i) structural role, acting as crosslinking nodes in the hydrogel and endowing it with shear-thinning (ability to flow under applied shear stress) and self-healing properties, and ii) functional role, imparting strong antibacterial and antioxidant activity. Remarkably, the in situ self-assembling of thiolated hyaluronic acid and Ag@Lig NPs yields nanocomposite hydrogels able to simultaneously inhibits the major factors involved in wound chronicity, namely the overexpressed deleterious proteolytic and oxidative enzymes, and high bacterial load. [Display omitted] [ABSTRACT FROM AUTHOR]

Monistic thermomechanics of eddy mater-space with metric stresses of Maxwellian type and inelastic metric waves can be developed for purely kinetic densities of the nonlocal mass-energy integral. Pseudo-Riemannian 4-geometry uses locally warped time to preserve the Euclidean sublight transport of nonlocally correlated densities with instantaneous metric connections and coherent conservation of local 4-currents everywhere. The kinematic viscosity of geometrised energy-momentum densities and their geodesic self-pushes by correlated metric stresses quantitatively clarify the adaptive all-unity of continuous kinetic energy, including material ether or variable rest-energy. The metric self-organisation of matter-space+time implies a nonlocal feedback of correlated eddy densities and their tensor response to the vector density of external forces. Such tensor inertial responses of correlated metric stresses reveal the nonlocal nature of turbulence and predict adaptive auto-modes or thermal waves of Euclidean material space due to the modified geodesic equation with viscose autowaves and the inverse Cavendish constant. The proposed nonlocal alternative to Euler/Navier-Stokes hydrodynamics can distinguish between Cartesian and Newtonian worldviews in conceptual laboratory probes of new macroscopic mechanics for metric self-organisations of thermokinetic energies of viscose material space without negative gravitational energies. [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]

Supramolecular hydrogel composed of aromatic short peptide gelator was an attractive biomaterial owing to its simple and convenient synthetic route, nano-fibrillar microstructure resembling natural collagen fibers and intelligent response to external stimulus. Herein, stimuli-responsive biphenyl-tripeptide supramolecular hydrogels was prepared to simulate extracellular matrix scaffolds by temperature switch, ion induction and pH switch. The amino acid arrangement substantially affected gelation behavior, only BPAA-βAFF and BPAA-FFβA could form nanostructured supramolecular hydrogels with 8-10 nm nanotubes or nanofibers by potential intermolecular hydrogen bond interactions and π-π stacking. The minimum gelation concentration (MGC) and maximum storage modulus were 0.4 mM (0.023 wt%) and around 8.2 KPa. The two supramolecular hydrogels could support adhesion and proliferation of L929 cells. Moreover, the BPAA-βAFF hydrogel promoted proliferation and ECM secretion of chondrocytes in vitro , and facilitate the phenotype maintenance of hyaline cartilage. All the results demonstrated that BPAA-βAFF hydrogel hold great potential application prospects in cartilage tissue engineering. Diphenylalanine was served as a core segment conjugating with 4-biphenylacetic acid (BPAA) to produce biphenyl-tripeptide compounds with transforming amino sequence, and multiple external stimuli was applied to study the gelation properties of the aromatic short peptide gelators. "FF" brick (phenylalanine-phenylalanine) was crucial for formation of fibrous supramolecular hydrogels. Meanwhile, the sequence of amino acids arrangement also had an essential effect on the gelation behavior. Optimal BPAA-βAFF with ultra-low minimum gelation concentration (0.4 mM, about 0.023 wt%) and similar microstructure to extracellular matrix (ECM) of nature cartilage tissue could promote the proliferation and ECM secretion of chondrocytes in vitro, and facilitate the formation of hyaline cartilage. [Display omitted] [ABSTRACT FROM AUTHOR]

Protein-based materials intended as nanostructured drugs or drug carriers are progressively gaining interest in nanomedicine, since their structure, assembly and cellular interactivity can be tailored by recruiting functional domains. The main bottleneck in the development of deliverable protein materials is the lysosomal degradation that follows endosome maturation. This is especially disappointing in the case of receptor-targeted protein constructs, which, while being highly promising and in demand in precision medicines, enter cells via endosomal/lysosomal routes. In the search for suitable protein agents that might promote endosome escape, we have explored the translocation domain (TD) of the diphtheria toxin as a functional domain in CXCR4-targeted oligomeric nanoparticles designed for cancer therapies. The pharmacological interest of such protein materials could be largely enhanced by improving their proteolytic stability. The incorporation of TD into the building blocks enhances the amount of the material detected inside of exposed CXCR4+ cells up to around 25-fold, in absence of cytotoxicity. This rise cannot be accounted for by endosomal escape, since the lysosomal degradation of the new construct decreases only moderately. On the other hand, a significant loss in the specificity of the CXCR4-dependent cellular penetration indicates the unexpected role of the toxin segment as a cell-penetrating peptide in a dose-dependent and receptor-independent fashion. These data reveal that the diphtheria toxin TD displayed on receptor-targeted oligomeric nanoparticles partially abolishes the exquisite receptor specificity of the parental material and it induces nonspecific internalization in mammalian cells.

In this paper, the tailoring of superhydrophobic surfaces on AA6082 aluminum alloy by chemical etching in an HF/HCl solution, followed by silane self-assembling, was applied for enhanced corrosion protection in the marine field. In particular, different etching times were considered in order to optimize the treatment effect. The results indicate that all the prepared surfaces, after silanization, were characterized by superhydrophobic behavior with a contact angle higher than 150°. The contact and sliding angles strongly depend on the surface morphology at varying etching times. The optimum was observed with an etching time of 20 s, where a microscale coral-like structure coupled with a homogeneous and ordered pixel-like nanostructure was obtained on the aluminum surface showing a Cassie–Baxter superhydrophobic behavior with a water contact angle of 180° and a sliding angle equal to 0°. All superhydrophobic surfaces achieved an enhanced corrosion protection efficiency and impedance modulus up to two orders of magnitude higher than the as-received AA6082 in simulated seawater.

Polarized beam infrared (IR) spectroscopy provides valuable information on changes in the orientation of samples in nematic phases, especially on the role of intermolecular interactions in forming the periodically modulated twist–bent phase. Infrared absorbance measurements and quantum chemistry calculations based on the density functional theory (DFT) were performed to investigate the structure and how the molecules interact in the nematic (N) and twist–bend (NTB) phases of thioether dimers. The nematic twist–bend phase observed significant changes in the mean IR absorbance. On cooling, the transition from the N phase to the NTB phase was found to be accompanied by a marked decrease in absorbance for longitudinal dipoles. Then, with further cooling, the absorbance of the transverse dipoles increased, indicating that transverse dipoles became correlated in parallel. To investigate the influence of the closest neighbors, DFT calculations were performed. As a result of the optimization of the molecular cores system, we observed changes in the square of the transition dipoles, which well corresponds to absorbance changes observed in the IR spectra. Interactions of molecules dominated by pairing were observed, as well as the axial shift of the core to each other.

The first iodide cluster of molybdenum with the metal cage in the form of a tetragonal pyramid (Bu4N)[Mo5OI13]·THF (I) and cocrystallizate (Bu4N){[Mo5OI13]0.9[Mo6I14]·THF (II) are synthesized for the first time by heating a LiI–I2–Mo mixture in a temperature range of 300–400°С followed by the extraction of the product. Complexes I and II are studied by X-ray diffraction analysis (CIF files CCDC nos. 2063029 (I) and 2063030 (II)). The molybdenum atoms in [Mo5OI13]– form a square pyramid with Mo–Mo distances of 2.67 Å between the basal molybdenum atoms and the Mo–Mo distances equal to 2.72 Å between the apical and basal molybdenum atoms. The oxygen atom is coordinated to the pyramid base (Mo–μ4-O 2.10 Å). The cluster anion [Mo5OI13]– can be presented as the octahedral cluster anion [Mo6I14]2– in which the position of the {MoI}– fragment (d0, 6e) is occupied by the isoelectronic oxygen atom (s2p4, 6e). In the structure of compound II, the [Mo5OI13]– and [Mo6I14]2– cluster anions occupy close atomic positions. [ABSTRACT FROM AUTHOR]

Green fluorescent protein (GFP) is a widely used scaffold for protein-based targeted nanomedicines because of its high biocompatibility, biological neutrality and outstanding structural stability. However, being immunogenicity a major concern in the development of drug carriers, the use of exogenous proteins such as GFP in clinics might be inadequate. Here we report a human nidogen-derived protein (HSNBT), rationally designed to mimic the structural and functional properties of GFP as a scaffold for nanomedicine. For that, a GFP-like β-barrel, containing the G2 domain of the human nidogen, has been rationally engineered to obtain a biologically neutral protein that self-assembles as 10nm-nanoparticles. This scaffold is the basis of a humanized nanoconjugate, where GFP, from the well-characterized protein T22-GFP-H6, has been substituted by the nidogen-derived GFP-like HSNBT protein. The resulting construct T22-HSNBT-H6, is a humanized CXCR4-targeted nanoparticle that selectively delivers conjugated genotoxic Floxuridine into cancer CXCR4+ cells. Indeed, the administration of T22-HSNBT-H6-FdU in a CXCR4-overexpressing colorectal cancer mouse model results in an even more efficient selective antitumoral effect than that shown by its GFP-counterpart, in absence of systemic toxicity. Therefore, the newly developed GFP-like protein scaffold appears as an ideal candidate for the development of humanized protein nanomaterials and successfully supports the tumor-targeted nanoscale drug T22-HSNBT-H6-FdU. Targeted nanomedicine seeks for humanized and biologically neutral protein carriers as alternative of widely used but immunogenic exogenous protein scaffolds such as green fluorescent protein (GFP). This work reports for the first time the rational engineering of a human homolog of the GFP based in the human nidogen (named HSNBT) that shows full potential to be used in humanized protein-based targeted nanomedicines. This has been demonstrated in T22-HSNBT-H6-FdU, a humanized CXCR4-targeted protein nanoconjugate able to selectively deliver its genotoxic load into cancer cells. [Display omitted] [ABSTRACT FROM AUTHOR]

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Volatile organic compounds (VOCs) are hazardous to the environment and human health. Thus, tremendous effort has gone into developing effective/efficient techniques for separation of VOCs from their aqueous mixtures. In this work, a simple and versatile strategy was proposed to fabricate a new material for hydrophobic VOC separations, in which a self-assembling hydrogel consisting of TEMPO-oxidized cellulose nanofibers (TOCNs) and cationic guar gum (CGG) was used. Specifically, TOCNs and CGG were deposited onto a filter paper via a layer-by-layer procedure, resulting in a TOCN/CGG hydrogel-coated filtering material, in which no crosslinking agent was used. The hydrogel is spontaneously formed by electrostatic interactions and hydrogen bonding. The as-prepared filtering material exhibits oil-repellence and underwater oleophobicity resulting from the formation of hydration layer on hydrogel, thus demonstrating good VOC separation performance. One-layer of TOCN/CGG hydrogel coating (dried mass of 0.032 g·m− 2) was proved to realize the VOC separation (separation efficiency of around 99 % and water flux of as high as 905.14 L·m− 2·h− 1). Further increase of the hydrogel layers has negligible influence on the separation efficiency although it decreases the water flux. This filtering material also exhibits good stability during recycling. Consequently, this TOCN/CGG self-assembling hydrogel-coated filtering material has great potential in VOCs-contaminated wastewater treatment. [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]

• Template-monomer binding affinity guide strategy was applied to investigate the optimal self-assembling conditions of H 3 AsO 3 MIPs. • The direct observation of dynamic evolution of targets recognition process was achieved by constructed annular imprinted cavity models with TEOS as cross-linkers. • Optimal self-assembling conditions for H 3 AsO 3 MIPs were proposed. • The critical distance for H 3 AsO 3 recognition away from cavity is 3.0 Å. • The dominant binding interaction was hydrogen bond, and the initial driving force for H 3 AsO 3 recognition was S-H···O formation. Molecular imprinted polymers (MIPs) have been recognized as good adsorbents to detect and remove As(Ш) from environment. 2-mercaptonicoic acid (2-M), having high affinity towards H 3 AsO 3 , is considered as potential functional monomer of H 3 AsO 3 MIPs. In this work, a template-monomer binding affinity guide strategy was applied to investigate self-assembling conditions of H 3 AsO 3 MIPs with 2-M as functional monomer, using quantum chemistry calculation and molecular dynamics simulation. Afterwards, dynamic recognition mechanism of H 3 AsO 3 MIPs was unraveled through imprinted cavity modelling for the first time. Results show that dichloromethane is the most suitable solvent, and 1:4:250 of H 3 AsO 3 , 2-M and dichloromethane is the best ratio. Remarkably, the direct observation of dynamic evolution of targets recognition was achieved by constructed annular imprinted cavity models with optimal 20 TEOS as cross-linkers. It was found that the critical distance for H 3 AsO 3 recognition is 3.0 Å. The dominant binding interaction is clarified to be hydrogen bond, and the initial driving force was S-H···O bond formation. This work provides not only a feasible strategy for computational design of good-performance MIPs, but also a method to perform recognition mechanism study by imprinted cavity modelling, which is significant for MIPs development as adsorbents for contaminants detection and removal from environment. [ABSTRACT FROM AUTHOR]

Abstract Background In recent years, multifunctional theranostic nanoparticles have been fabricated by integrating imaging and therapeutic moieties into one single nano-formulations. However, Complexity of production and safety issues limits their further application. Results Herein, we demonstrated self-assembled nanoparticles with single structure as a “from one to all” theranostic platform for tumor-targeted dual-modal imaging and programmed photoactive therapy (PPAT). The nanoparticles were successfully developed through self-assembling of hyaluronic acid (HA)-cystamine-cholesterol (HSC) conjugate, in which IR780 was simultaneously incorporated (HSCI NPs). Due to the proper hydrodynamic size and intrinsic targeting ability of HA, the HSCI NPs could accumulate at the tumor site effectively after systemic administration. In the presence of incorporated IR780, in vivo biodistribution and accumulation behaviors of HSCI NPs could be monitored by photoacoustic imaging. After cellular uptake, the HSCI NPs would disintegrate resulting from cystamine reacting with over-expressed GSH. The released IR780 would induce fluorescence “turn-on” conversion, which could be used to image tumor sites effectively. Upon treatment with 808 nm laser irradiation, PPAT could be achieved in which generated reactive oxygen species (ROS) would produce photodynamic therapy (PDT), and subsequently the raised temperature would be beneficial to tumor photothermal therapy (PTT). Conclusion The self-assembled HSCI NPs could act as “from one to all” theranostic platform for high treatment efficiency via PPAT pattern, which could also real-time monitor NPs accumulation by targeted and dual-modal imaging in a non-invasive way.

Tissue regeneration is a prominent area of research, developing biomaterials aimed to be tunable, mechanistic scaffolds that mimic the physiological environment of the tissue. These biomaterials are projected to effectively possess similar chemical and biological properties, while at the same time are required to be safely and quickly degradable in the body once the desired restoration is achieved. Supramolecular systems composed of reversible, non-covalently connected, self-assembly units that respond to biological stimuli and signal cells have efficiently been developed as preferred biomaterials. Their biocompatibility and the ability to engineer the functionality have led to promising results in regenerative therapy. This review was intended to illuminate those who wish to envisage the niche translational research in regenerative therapy by summarizing the various explored types, chemistry, mechanisms, stimuli receptivity, and other advancements of supramolecular systems.

Ferritins are ideal nanoparticles as drug delivery systems due to their hollow-sphere structure and the ability to target specific receptors on the cell surface. Here, we develop and characterize a new ferritin derived from the chimeric humanized A. fulgidus one, already designed to recognize the TfR1 receptor. Starting from the synthetic gene of this chimeric protein, we replaced two positively charged amino acids with two alanine residues to close the large triangular pores on its surface. These mutations make the protein nanoparticle suitable to incorporate even small therapeutics without leakage. Size-exclusion chromatography shows that the assembling/disassembling of this new protein cage can be easily fine-tuned by varying the HEPES buffer and MgCl2 concentration. The protein cage can be opened using 150 mM HEPES buffer without magnesium ions. Adding this divalent cation to the solution promotes the quick assembly of the ferritin as a 24-mer. The development of this new protein cage paves the way for encapsulation and delivery studies of small molecules for therapeutic and diagnostic purposes.

Surface-enhanced Raman spectroscopy (SERS) is regarded as a versatile tool for studying the composition and structure of matter. This work has studied the preparation of a SERS substrate based on a self-assembling plasmonic nanoparticle film (SPF) in a polymer matrix. Several synthesis parameters for the SPF are investigated, including the size of the particles making up the film and the concentration and type of the self-assembling agent. The result of testing systems with different characteristics is discussed using a model substance (pseudoisocyanin iodide). These models can be useful in the study of biology and chemistry. Research results contain the optimal parameters for SPF synthesis, maximizing the SERS signal. The optimal procedure for SPF assembly is determined and used for the synthesis of composite SPFs within different polymer matrices. SPF in a polymer matrix is necessary for the routine use of the SERS substrate for various types of analytes, including solid samples or those sensitive to contamination. Polystyrene, polyvinyl alcohol (PVA), and polyethylene are investigated to obtain a polymer matrix for SPF, and various methods of incorporating SPF into a polymer matrix are being explored. It is found that films with the best signal enhancement and reproducibility were obtained in polystyrene. The minimum detectable concentration for the SERS substrate obtained is equal to 10−10 M. We prepared a SERS substrate with an analytical enhancement factor of 2.7 × 104, allowing an increase in the detection sensitivity of analyte solutions of five orders of magnitude.

We studied self-assembled plasmonic films (SPF) based on gold nanoparticles (Au-NPs). We recorded the intensity distribution maps (IDM) with an area of 2025 μm2 (9 × 9 points). We have observed uniform enhancement across the entire surface of SPF. Therefore, we used the parameters average intensity of IDM and IDM gate when we optimized the synthesis of SPF. Average intensity is the average intensity value over 81 spectra of the IDM. The gate is the span excluding 10% of the outliers. We have discovered that the maximum average intensity was observed at a concentration of 1.00 × 10–5 M. A decrease in the concentration of Au-NPs leads to a decrease in the average intensity. A simultaneous decrease in TOABr and A-u‑NPs concentration also leads to a decrease in the average intensity. The film obtained by the optimal synthesis method was characterized using SEM and AFM. [ABSTRACT FROM AUTHOR]

The self-assembling behavior of Bombyx mori silkworm fibroin was investigated focusing on the interaction of the two types of silkworm sericin fractions (P, M) with the fibroin in the static and flow states. The dissociation of the sericin M fraction from the fibroin allowed the fibroin to form the silk2 crystal guided by the sericin P fraction still interacting with the fibroin. Water annealing in room temperature water, or the enzymatic hydrolysis caused by the contamination by fibroinase, weakened the interaction between the fibroin and the sericin M fraction. Thus, the interaction of the sericin P fraction with the fibroin was considered to be more stable than that of the sericin M fraction. As a result all of the entities that assembled in the flow state gave almost similar WAXD intensity curves although the coagulation conditions were changed at every trial. The morphology of the entities obtained in the flow state became film-like when a two-dimensional interface was generated between the fibroin and the free sericin molecules. On the other hand, it became fibrous when the fibroin interacted with a new protein fraction (a minor protein fraction that can cause the solution of fibroin into water) instead of the sericin fractions. [ABSTRACT FROM AUTHOR]

Zhang Y, Zhou J, Yang C, et al. Int J Nanomedicine. 2016;11:1119–1130. The authors have advised due to an error at the time of figure assembly, Figure 4 on page 1124 is incorrect. The correct Figure 4 is shown in Download Article. Page 1126, Table 1, the authors have advised a mistake was made in calculating the Drug loading content (DLC) in the manuscript. The correct Table 1 is shown in Download Article. The authors apologize for these errors and advise it does not affect the results of the paper. Read the original article

Au nanoparticles functionalized by short poly(ethylene glycol) chain ligands were suspended in a hydroalcoholic medium. This suspension was then printed by inkjet onto a Kapton® substrate. Gold electrodes consisting of four stacked printed layers exhibited a conductivity of (1 ± 0.1) × 107 S/m, close to that of Au bulk, after low-temperature thermal annealing. The electrochemical behaviour with respect to heterogeneous electron transfer reactions and the reactivity towards thiol chemisorption are identical to those obtained when a conventional polycrystalline Au electrode is used.

In this data file the synthetic procedures for preparation of the original 4-pyridinium-1,4-dihydropyridines (4-Py-1,4-DHP) and their parent compounds – dialkyl 2,6-dimethyl-4-(3-pyridyl)-1,4-dihydropyridine-3,5-dicarboxylates were described. In total, 5 unpublished compounds were obtained and characterised. All the structures of original compounds were confirmed by Nuclear Magnetic Resonance (NMR, including 1H NMR and 13C NMR) and low resolution mass spectra (MS) data. Additionally, the cytotoxic properties of four 4-Py-1,4-DHPs were evaluated on 3 cell lines – normal NIH3T3 (mouse embryonic fibroblast), cancerous HT-1080 (human lung fibrosarcoma) and MH-22A (mouse hepatoma) and self-assembling properties were studied and characterisation of formed nanoparticles were performed using dynamic light scattering technique. In this article provided data are directly related to the previously published research articles – “Novel cationic amphiphilic 1,4-dihydropyridine derivatives for DNA delivery” [1] where compound 5 was tested as gene delivery agent without full physico-chemical characterisation and “Synthesis and studies of calcium channel blocking and antioxidant activities of novel 4-pyridinium and/or N-propargyl substituted 1,4-dihydropyridine derivatives” [2] where synthesis and physico-chemical characterisation as well as calcium channel blocking and antioxidant activities were described for compound 6. Synthesis of other compounds – parent 1,4-DHPs 1 and 2, and 4-Py-1,4-DHPs 3–5, their characterisation, estimation of cytotoxicity and self-assembling properties for all 4-Py-1,4-DHPs 3–6 are reported herein for the first time. Information provided in this data file can be used in medicinal chemistry by other scientists to estimate structure-activity relationships for the analysis and construction of various cationic 1,4-dihydropyridine derivatives and related heterocycles.

Metallic nano multilayers were usually prepared by dual targets alternating deposition method. In this paper, a series of self-assembled Cu–W nano multilayers with different modulation periods were deposited on single crystal silicon substrate by dual targets confocal magnetron sputtering technique. The self-assembled film presented an alternation of W-rich layer and Cu-rich layer. The degree of coherence of the layered interface can be adjusted by controlling both the solid solubility of W-rich and Cu-rich layers. The film resistance increment of the self-assembled Cu–W multilayers is only 14% when the modulation period decreases from 68.2 nm to 5.3 nm, having less size effect compared to the film prepared by alternating deposition method. It noticed that the film resistance even decreased slightly when the modulation period decreased to below 5.3 nm. These results suggested that the coherence could weak the interface scattering ability to electrons, so the self-assembled Cu–W multilayers have lower resistance than the multilayer prepared by alternating deposition technique. This study presented a new pathway to enhance the conductivity of the multilayers. [ABSTRACT FROM AUTHOR]

Nature is a source of inspiration for the self-assembly of functional molecular nanoarchitectures based on intermolecular bonds. This work investigates the self-assembly of molecules (i) polyacrylic acid (PAA, COO– group), (ii) cetyltrimethylammonium (CTA+), and (iii) alkylimidazole (ImR, imidazole group) as building blocks with different properties and functionalities. For the dephosphorylation reaction of diethyl 2,4-dinitrophenyl phosphate (DEDNPP) in aqueous medium, the building blocks PAA, ImR, and CTA+ did not show relevant catalytic activity. An increase in the rate constant was observed from the critical aggregation concentration (CAC) between the polymer and surfactant. This result was related to the formation of hydrophobic pockets of the nanostructured supramolecular complexes. For the PAA/CTAB/ImR system, the formation of hydrophobic microenvironments made it possible to partition the DEDNPP to regions close to the catalytic site. The increase in the rate constant was up to 1.5 × 107-fold higher than that obtained with spontaneous hydrolysis. Thus, the extensive catalytic activity of the self-assembled multicomponent nanoreactor demonstrated potential because of its ease of obtainment and its variety of characteristics. Therefore, the combination of different functional macromolecules is a strategy for the development of inexpensive, efficient, and selective nanocatalysts with characteristics similar to enzymes, the best-known catalysts. [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]

Immunomodulatory therapies are limited by unavoidable side effects as well as poor solubility, stability, and pharmacokinetic properties. Nanomaterial-based drug delivery may overcome these limitations by increasing drug solubility, site-targeting, and duration of action. Here, we prepared innovative drug-integrating amphiphilic nanomaterial assemblies (DIANA) with tunable hydrophobicity, size, and morphology, and we evaluated their ability to deliver cyclosporine A (CsA) for immunomodulatory applications. We synthesized amphiphilic block copolymers made of poly(ethylene glycol)-poly(propylene sulfide) (PEG-PPS) and poly(ethylene glycol)-oligo(ethylene sulfide) (PEG-OES) that can self-assemble into solid core nanomicelles (nMIC, with ≈20 nm diameter) and nanofibrils (nFIB, with ≈5 nm diameter and > 500 nm length), respectively. nMIC and nFIB displayed good CsA encapsulation efficiency (up to 4.5 and 2 mg/mL, respectively in aqueous solution), superior to many other solubilization methods, and provided sustained release (>14 and > 7 days for the nMIC and nFIB) without compromising CsA's pharmacological activity. Treatment of insulin-secreting cells with unloaded DIANAs did not impair cell viability and functionality. Both CsA-loaded DIANAs inhibited the proliferation and activation of insulin-reactive cytotoxic T cells in vitro. Subcutaneous injections of CsA-loaded DIANAs in mice provided CsA sustained release, decreasing alloantigen-induced immune responses in the draining lymph node at lower doses and reduced administration frequency than unformulated CsA. While nMIC solubilized higher amounts and provided more sustained release of CsA in vitro , nFIB enhanced cellular uptake and promoted local retention due to slower trafficking in vivo. DIANAs provide a versatile platform for a local immune suppression regimen that can be applied to allogeneic cell transplantation. Unlabelled Image • Drug-Integrating Amphiphilic Nanomaterial Assemblies (DIANA) made of block-copolymerssolubilizehigh amounts of cyclosporine. • DIANAs provide more sustained & localized delivery. • DIANAs are efficiently taken up by T cells in vitro and in vivo in the lymph-nodes. • The shape and size of DIANAs influence the spatiotemporal drug delivery. • DIANAs can reduce or avoid systemic side effects due to less frequent administrations and localized drug release. [ABSTRACT FROM AUTHOR]

Four truxeneones 6a-d in which three long alkoxy chains and three methoxy groups were C3-symmetrically attached to the truxenone core have been synthesised and studied with the aim to study the effect of bulky methoxy substituents on their mesomorphism and self-assembly properties. These four compounds show enantiotropic mesophase and each has a Colh phase over a 135°C temperature range. A comparison of the side chains showed that 6a-d with mixed alkoxy chains display more complex thermotropic behaviour than reported truxenones possessing six identical long alkoxy chains. Although the methoxy groups have almost no effect on their self-assembly in solution due to the staggered face-to-face arrangement of truxenone moieties, it is confirmed that replacement of three long alkoxy chains by methoxy groups may affect the packing of molecules in the crystalline state more than that within the mesophase. The presence of methoxy groups results in lowering of both the clearing point and the temperature range of the Colh phases by maintaining high melting point. Moreover, 6a self-assembles on a solid/liquid interface into a well-ordered two-dimensional architecture which was explored using high-resolution STM that closely resembles to the proposed bulk mesomorphic three-dimensional columnar phase deduced from XRD. [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]

The rapid development of antimicrobial resistance is pushing the search in the discovering of novel antimicrobial molecules to prevent and treat bacterial infections. Self-assembling antimicrobial peptides, as the lipidated peptides, are a novel and promising class of molecules capable of meeting this need. Based on previous work on Temporin L analogs, several new molecules lipidated at the N- or and the C-terminus were synthesised. Our goal is to improve membrane interactions through finely tuning self-assembly to reduce oligomerisation in aqueous solution and enhance self-assembly in bacterial membranes while reducing toxicity against human cells. The results here reported show that the length of the aliphatic moiety is a key factor to control target cell specificity and the oligomeric state of peptides either in aqueous solution or in a membrane-mimicking environment. The results of this study pave the way for the design of novel molecules with enhanced activities. [ABSTRACT FROM AUTHOR]

Summary: Gel formation using guanosine self-assembly is an important process in supramolecular chemistry. Here, we report the stepwise construction of circularly polarized luminescent supramolecular organogels from self-assembled guanosine quadruplexes. A lipophilic guanosine derivative (aldG) is designed and synthesized for the formation of a well-defined G8-octamer. The diamine linkers are used to connect G8-octamer units by imine formation to facilitate the construction of the supramolecular gel networks. 1H NMR experiments show that the pre-assembled aldG8-octamer remains intact and is crucial for transparent and stiff organogel formation. With extended conjugation, the aldG organogels exhibit strong green fluorescence emission and circularly polarized properties without the assistance of any external fluorescent dyes, suggesting an alternative approach to construct molecular probes for biological and material applications.

Self-assembling peptides can be used to design new materials for medical and biological applications. Here we synthesized and characterized two novel cyclic γ-peptides (γ-CPs) with hydrophobic inner surfaces. The NMR and FT-IR studies confirmed that the CPs could self-assemble into parallel stacking structures via intermolecular H-bonds and π-π interactions. The morphologies of the self-assembly CPs showed bundles of nanotubes via transmission electron microscopy (TEM); these nanotubes form water channels to transport water across the lipid membrane. The properties of blocking the transport of protons like natural water channels showed that the hydrophobic inner surfaces are important in artificial transmembrane water channel designs. These studies also showed that water transport was a function of pore size and length of the assemblies.

Background: Human-induced pluripotent stem cell-derived hepatocytes (iHeps) have been shown to have considerable potential in liver diseases, toxicity, and pharmacological studies. However, there is a growing need to obtain iHeps that are truly similar to primary adult hepatocytes in terms of morphological features and functions. We generated such human iHeps, self-assembled as organoids (iHep-Orgs). Methods: iPSC-derived hepatoblasts were self-assembled into spheroids and differentiated into mature hepatocytes modulating final step of differentiation. Results: In about four weeks of culture, the albumin secretion levels and the complete disappearance of α-fetoprotein from iHep-Orgs suggested the acquisition of a greater degree of maturation than those previously reported. The expression of apical transporters and bile acid secretion evidenced the acquisition of complex hepatocyte polarity as well as the development of a functional and well-defined bile canalicular network confirmed by computational analysis. Activities recorded for CYP450, UGT1A1, and alcohol dehydrogenase, response to hormonal stimulation, and glucose metabolism were also remarkable. Finally, iHep-Orgs displayed a considerable ability to detoxify pathological concentrations of lactate and ammonia. Conclusions: With features similar to those of primary adult hepatocytes, the iHep-Orgs thus produced could be considered as a valuable tool for the development and optimization of preclinical and clinical applications.

The study was aimed at formulating self-assembled capsaicin prodrug nanoparticles (Cap-SSVE NPs) with improved bioavailability, increased antihyperlipidemic activity and less gastrointestinal mucosa irritations. The in vitro release profile of the developed Cap-SSVE NPs was stable in HCl solution (pH 1.2) and distilled water, but very susceptible in PBS (pH 6.8 and 7.4). The relative oral bioavailability of Cap-SSVE NPs was 3.2 folds higher than free capsaicin, with an extended Tmax (0.25–1 h). The Cap-SSVE NPs decreased certain lipid profile indices of both the liver tissue (Total lipids and TG) and the blood sample (TC, TG, LDL and TBA) with elevated levels of HDL in high fat diet induced hyperlipidemic rats. The nanoparticles also predominantly accumulated in the liver with reduced irritations in the gastrointestinal mucosa. Collectively, the formulated Cap-SSVE NPs showed an enhanced bioavailability, increased hypolipidemic effects and reduced mucosa irritations.

The aim of the research was to check whether it is possible to use fragments of type IV collagen to obtain, as a result of self-assembling, stable spatial structures that could be used to prepare new materials useful in regenerative medicine. Collagen IV fragments were obtained by using DMT/NMM/TosO− as a coupling reagent. The ability to self-organize and form stable spatial structures was tested by the CD method and microscopic techniques. Biological studies covered: resazurin assay (cytotoxicity assessment) on BJ, BJ-5TA and C2C12 cell lines; an alkaline version of the comet assay (genotoxicity), Biolegend Legendplex human inflammation panel 1 assay (SC cell lines, assessment of the inflammation activity) and MTT test to determine the cytotoxicity of the porous materials based on collagen IV fragments. It was found that out of the pool of 37 fragments (peptides 1–33 and 2.1–2.4) reconstructing the outer sphere of collagen IV, nine fragments (peptides: 2, 4, 5, 6, 14, 15, 25, 26 and 30), as a result of self-assembling, form structures mimicking the structure of the triple helix of native collagens. The stability of spatial structures formed as a result of self-organization at temperatures of 4 °C, 20 °C, and 40 °C was found. The application of the MST method allowed us to determine the Kd of binding of selected fragments of collagen IV to ITGα1β1. The stability of the spatial structures of selected peptides made it possible to obtain porous materials based on their equimolar mixture. The formation of the porous materials was found for cross-linked structures and the material stabilized only by weak interactions. All tested peptides are non-cytotoxic against all tested cell lines. Selected peptides also showed no genotoxicity and no induction of immune system responses. Research on the use of porous materials based on fragments of type IV collagen, able to form stable spatial structures as scaffolds useful in regenerative medicine, will be continued.

In this work, to improve the friction and wear properties of carbon fiber (CF) reinforced resin-based composites (CFRC), silicon carbide (SiC) @ γ-Aminopropyl triethoxysilane (Kh550) was self-assembled on the surface of CF. Compared to the unmodified CFRC, the dynamic friction coefficients of modified ones with different grafting time increased by 0.05, 0.1 and 0.1, respectively, while the wear rates correspondingly dropped sharply by 79%, 56% and 25%, respectively. According to the Raman spectroscopic analysis of worn surfaces, the stress distributions of modified samples were uniform and the stress concentration points decreased. Grafted SiC@Kh550 particles could absorb energy, which was beneficial to increasing the interfacial stress between CF and phenolic resin, thereby alleviating fatigue wear. [ABSTRACT FROM AUTHOR]

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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 aim of this study is to develop a methodology in which Surface Plasmon Resonance (SPR), Ellipsometer (EM) and Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry (MALDI-MS) will be used together for detection of single-strand oligodeoxynucleotides (ssODNs) targets. A selected target-ssODNs, and its complementary, the probe-ssODNs carrying a -SH end group, a spacer arm (HS-(CH2)6–(T)15, and a non-complementary ssODNs were used. Silicone based stamps with 16 regions were prepared and used for micro-contact printing (µCP) of the probe-ssODNs on the gold coated surfaces homogeneously. A modulator-spacer molecule (6-mercapto-1-hexanol) was co-immobilized to control surface probe density, to orientate the probe-ssODNs, and to eliminate the nonspecific interactions. SPR was used successfully to follow the hybridization of the target-ssODNs with the immobilized probe-ssODNs on the platform surfaces. Complete hybridizations were achieved in 100 min. It was obtained that there was a linear relationship between relative change in delta and target concentration below 1 µm. Using imaging version of ellipsometer (IEM) allowed imaging of the surfaces and supported extra datum for the SPR results. After a very simple dehybridization protocol, MALDI-MS analysis allowed detection of the target-ssODNs hybridized on the sensor/array platforms. [ABSTRACT FROM AUTHOR]

Current therapies fail to eradicate colorectal Cancer Stem Cells (CSCs). One of the proposed reasons for this failure is the selection, by chemotherapy exposure, of resistant cells responsible for tumor recurrence. In this regard, CXCR4 overexpression in tumor associates with resistance and poor prognosis in colorectal cancer (CRC) patients. In this study, the effectiveness of engineered CXCR4-targeted self-assembling toxin nanoparticles has been explored in the selective killing of CXCR4+ human colon-CSCs compared to 5-Fluorouracil and Oxaliplatin, both classical CRC chemotherapeutic agents. To assess this, 3D spheroid colon-CSCs cultures directly derived from CRC patients and CRC-CSC spheroid-derived tumor mouse models were developed. In these animal models, nanostructured toxins show highly selective induction of pyroptosis in the absence of apoptosis, thus having a great potential to overcome tumor resistance, since the same tumor models show resistance to chemotherapeutics. Results set the basis for further development of more efficient therapies focused on selective CXCR4+ CSCs elimination activating non-apoptotic mechanisms and represent a pre-clinical proof of concept for the use of CSCs-targeted nanostructured toxins as protein drugs for CRC therapy. The effectiveness of CXCR4-targeted self-assembling toxin-based nanoparticles against colon cancer stem cells has been demonstrated overcoming issues of improve therapeutic efficacy and drug resistance. These nanoparticles lead to the eradication of apoptotic-resistant cell population in colon cancer stem cell tumors by triggering pyroptotic cell death. Unlabelled Image • Current therapies fail to eradicate colorectal cancer stem cells (CRC-CSCs) due to their potent anti-apoptotic defenses. • Upregulation of the chemokine receptor CXCR4 plays a critical role in developing resistance to chemotherapy. • CXCR4-targeted toxins kill CRC-CSCs in form of nanoparticles with highly selective antitumor effect. • Targeted toxins induce pyroptosis when apoptosis is blocked, with a great therapeutic potential in drug-resistant tumors. [ABSTRACT FROM AUTHOR]

Field induced assembling/disassembling of paramagnetic colloids is strongly influenced by the configuration of the applied field, the surface chemistry of the particles, the nearby presence of an external boundary or the particle density. The trapping of the particles at fluid-fluid interface is expected to promote different assembling/disassembling routes together with new approaches for controlled manipulation of self-assembled structures and the fabrication of new functional patterned surfaces. We study the reversible disassembly itineraries that emerge in linear aggregates of micrometer-sized magnetic particles adsorbed onto a fluid interface when the applied field is abruptly tilted out of the confining surface: the unzipping of chains laterally aggregated, the partial fragmentation of the chains, the gradual separation of the monomers and the abrupt colloidal explosion. By combining experiments, simulations and theoretical arguments, we elucidate different dissociation mechanisms strongly influenced by subtle changes in the orientation of the applied field, the particle's position relative to the confining interface and the mutual induction of the particles. Moreover, we show that the understanding of the mechanisms can be applied to pinpoint exactly particle detachments in two-dimensional binary mixtures. [ABSTRACT FROM AUTHOR]

Biomanufacturing of chemicals using biocatalysts is an attractive strategy for the production of valuable pharmaceuticals since it is usually more economical and has a much-reduced environmental impact. However, there are often challenges such as their thermal instability that should be overcome before a newly discovered enzyme is eventually translated into industrial processes. In this work, we describe a roadmap for the development of a robust catalyst for industrial resolution of Vince lactam, a key intermediate for the synthesis of carbocyclic-nucleoside-related pharmaceuticals. By a genome mining strategy, a new (+)-γ-lactamase (MiteL) from Microbacterium testaceum was successfully discovered and biochemically characterized. In vitro studies showed that the enzyme exhibited high activity but poor enantioselectivity (E = 6.3 ± 0.2) toward racemic Vince lactam, and thus, it is not suitable for industrial applications. Based on structural modeling and docking studies, a semi-rational engineering strategy combined with an efficient screening method was then applied to improve the enantioselectivity of MiteL. Several mutants with significant shifting stereoselectivity toward (−)-γ-lactam were obtained by site-saturation mutagenesis. Synergy effects led to the final mutant F14D/Q114R/M117L, which enabled efficient acquisition of (−)-γ-lactam with a high E value (> 200). The mutant was biochemically characterized, and the docking studies suggested a plausible mechanism for its improved selectivity. Finally, a sunflower-like nanoreactor was successfully constructed to improve the mutant's robustness via protein supramolecular self-assembly. Thus, the synergism between semi-rational protein engineering and self-assembling immobilization enabled construction of a nanoreactor with superior properties, which can be used for resolution of Vince lactam in large scale. [ABSTRACT FROM AUTHOR]

Fluorescent proteins are useful imaging and theranostic agents, but their potential superiority over alternative dyes is weakened by substantial photobleaching under irradiation. Enhancing protein photostability has been attempted through diverse strategies, with irregular results and limited applicability. In this context, we wondered if the controlled oligomerization of Green Fluorescent Protein (GFP) as nanoscale supramolecular complexes could stabilize the fluorophore through the newly formed protein-protein contacts, and thus, enhance its global photostability. For that, we have here analyzed the photobleaching profile of several GFP versions, engineered to self-assemble as tumour-homing nanoparticles with different targeting, size and structural stability. This has been done under prolonged irradiation in confocal laser scanning microscopy and by small-angle X-ray scattering. The results show that the oligomerization of GFP at the nanoscale enhances, by more than seven-fold, the stability of fluorescence emission. Interestingly, GFP nanoparticles are much more resistant to X-ray damage than the building block counterparts, indicating that the gained photostability is linked to enhanced structural resistance to radiation. Therefore, the controlled oligomerization of self-assembling fluorescent proteins as protein nanoparticles is a simple, versatile and powerful method to enhance their photostability for uses in precision imaging and therapy. Fluorescent protein assembly into regular and highly symmetric nanoscale structures has been identified to confer enhanced structural stability against radiation stresses dramatically reducing their photobleaching. Being this the main bottleneck in the use of fluorescent proteins for imaging and theranostics, this protein architecture engineering principle appears as a powerful method to enhance their photostability for a broad applicability in precision imaging, drug delivery and theranostics. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Background: The use of biomaterials has been expanded to improve the characteristics of vaccines. Recently we have identified that the peptide PH(1–110) from polyhedrin self-aggregates and incorporates foreign proteins to form particles. We have proposed that this peptide can be used as an antigen carrying system for vaccines. However, the immune response generated by the antigen fused to the peptide has not been fully characterized. In addition, the adjuvant effect and thermostability of the particles has not been evaluated. Results: In the present study we demonstrate the use of a system developed to generate nano and microparticles carrying as a fusion protein peptides or proteins of interest to be used as vaccines. These particles are purified easily by centrifugation. Immunization of animals with the particles in the absence of adjuvant result in a robust and long-lasting immune response. Proteins contained inside the particles are maintained for over 1 year at ambient temperature, preserving their immunological properties. Conclusion: The rapid and efficient production of the particles in addition to the robust immune response they generate position this system as an excellent method for the rapid response against emerging diseases. The thermostability conferred by the particle system facilitates the distribution of the vaccines in developing countries or areas with no electricity. [ABSTRACT FROM AUTHOR]