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With the aim to design addressable magnetically-active carbon nanotubes (CNTs) for cancer treatment, the use of Fe-fi lled CNTs (Fe@MWCNTs) as multifunctional scaffolds is reported for exohedrally anchoring a monoclonal antibody (mAb) known to bind a plasma membrane receptor over-expressed in several cancer cells (EGFR). Comprehensive microscopic (transmission electron microscopy, atomic force microscopy, and scanning electron microscopy) and spectroscopic (Raman, 57 Fe Mossbauer, energy dispersive spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction) characterizations reveal the effi cient confi nement of magnetically-active Fe phases ( α -Fe and Fe 3 C), while compositional evaluations through XPS, thermogravimetric analysis and gel electrophoresis confi rm that mAb immobilization onto Fe@MWCNTs occurs. Enzyme-linked immunosorbent assay (ELISA), confocal microscopy imaging and western blotting confi rm the targeting action toward EGFR-overexpressing cell lines (EGFR + ). In vitro magnetic fi ltration experiments demonstrate that a selective removal of EGFR + cells from a mixed population of healthy cell linescould be obtained in very short times ( ≈ 10 min). Cytotoxicity evaluations by classic cell staining procedures after application of an electromagnetic radiation inducing magnetic fl uid hyperthermia (MFH), show a selective suppression of the EGFR + cell line. Molecular dynamics and docking simulations of the hybrid mAb/Fe@MWCNTs conjugates nicely show how the presence of the CNT framework does not sterically affect the conformational properties of the two antigen binding regions, further supporting the biochemical fi ndings.

The synthesis, X-ray crystal structures, ground- and excited-state UV/Vis absorption spectra, and luminescence properties of chalcogen-doped organic emitters equipped on both extremities with benzoxa-, benzothia-, benzoselena- and benzotellurazole (1X and 2X ) moieties have been reported for the first time. The insertion of the four different chalcogen atoms within the same molecular skeleton enables the investigation of only the chalcogenic effect on the organisation and photophysical properties of the material. Detailed crystal-structure analyses provide evidence of similar packing for 2O -2Se , in which the benzoazoles are engaged in π-π stacking and, for the heavier atoms, in secondary X⋅⋅⋅X and X⋅⋅⋅N bonding interactions. Detailed computational analysis shows that the arrangement is essentially governed by the interplay of van der Waals and secondary bonding interactions. Progressive quenching of the fluorescence and concomitant onset of phosphorescence features with gradually shorter lifetimes are detected as the atomic weight of the chalcogen heteroatom increases, with the tellurium-doped derivatives exhibiting only emission from the lowest triplet excited state. Notably, the phosphorescence spectra of the selenium and tellurium derivatives can be recorded even at room temperature; this is a very rare finding for fully organic emitters.

The synthesis of O‐doped polyaromatic hydro‐ carbons in which two polycyclic aromatic hydrocarbon sub units are bridged through one or two O atoms has been achieved. This includes high‐yield ring‐closure key steps that, depending on the reaction conditions, result in the formation of furanyl or pyranopyranyl linkages through intramolecular C−O bond formation. Comprehensive photophysical measurements in solution showed that these compounds have exceptionally high emission yields and tunable absorption properties throughout the UV/Vis spectral region. Electrochemical investigations showed that in all cases O annulation increases the electron‐donor capabilities by raising the HOMO energy level, whereas the LUMO energy level is less affected. Moreover, third‐order nonlinear optical (NLO) measurements on solutions or thin films containing the dyes showed very good values of the second hyperpolarizability. Importantly, poly(methyl methacrylate) films containing the pyranopyranyl derivatives exhibited weak linear absorption and NLO absorption compared to the nonlinearity and NLO refraction, respectively, and thus revealed them to be exceptional organic materials for photonic devices.

Because of the peculiar dynamic covalent reactivity of boronic acids to form tetraboronate derivatives, interest in using their aryl derivatives in materials science and supramolecular chemistry has risen. Nevertheless, their ability to form H-bonded complexes has been only marginally touched. Herein we report the first solution and solid-state binding studies of the first double-H-bonded DD·AA-type complexes of a series of aromatic boronic acids that adopt a syn-syn conformation with suitable complementary H-bonding acceptor partners. The first determination of the association constant (K) of ortho-substituted boronic acids in solution showed that K for 1:1 association is in the range between 300 and 6900 M. Crystallization of dimeric 1:1 and trimeric 1:2 and 2:1 complexes enabled an in-depth examination of these complexes in the solid state, proving the selection of the -B(OH) syn-syn conformer through a pair of frontal H-bonds with the relevant AA partner. Non-ortho-substituted boronic acids result in "flat" complexes. On the other hand, sterically demanding analogues bearing ortho substituents strive to retain their recognition properties by rotation of the ArB(OH) moiety, forming "T-shaped" complexes. Solid-state studies of a diboronic acid and a tetraazanaphthacene provided for the first time the formation of a supramolecular H-bonded polymeric ribbon. On the basis of the conformational dynamicity of the -B(OH) functional group, it is expected that these findings will also open new possibilities in metal-free catalysis or organic crystal engineering, where double-H-bonding donor boronic acids could act as suitable organocatalysts or templates for the development of functional materials with tailored organizational properties.

Through the simultaneous use of three orthogonal dynamic covalent reactions, namely disulfide, boronate, and acyl hydrazone formation, we conceived a facile and versatile protocol to spatially organize tailored chromophores, which absorb in the blue, red, and yellow regions, on a preprogrammed α-helix peptide. This approach allowed the assembly of the dyes in the desired ratio and spacing, as dictated by both the relative positioning and distribution of the recognition units on the peptide scaffold. Steady-state UV/Vis absorption and emission studies suggest an energy transfer from the yellow and red donors to the blue acceptor. A molecular dynamics simulation supports the experimental findings that the helical structure is maintained after the assembly and the three dyes are confined in defined conformational spaces.

This critical review aims at giving insights on the spontaneous tendency of proteins and their constitutive parts to adsorb on graphitic nanomaterials (GNMs) through non-covalent interactions occurring at their interfaces. Specifically, it focuses on the theoretical and experimental studies carried out to comprehend in depth the forces ruling the adsorption processes of proteins on fullerene, carbon nanotubes and graphene. In a systematic way the reader is guided through the most recent and representative examples describing at the atomistic level of detail the structural modalities and the chemico-physical principles through which amino acids, polypeptides and folded proteins interact with GNMs' surface, thereby taking into consideration the mutual effects of both protein structural complexity and nanomaterial topology. Based on their chemical and structural features, the study and understanding of the protein-nanomaterial interfaces can be exploited in the view of design and control the spontaneous formation of biologically-active hybrid materials for the development of new tailored applications in the field of sensing, nanomedicine and biochemistry.

Extracellular HMGB1 triggers inflammation following infection or injury and supports tumorigenesis in inflammation‐related malignancies. HMGB1 has several redox states: reduced HMGB1 recruits inflammatory cells to injured tissues forming a heterocomplex with CXCL12 and signaling via its receptor CXCR4; disulfide‐containing HMGB1 binds to TLR4 and promotes inflammatory responses. Here we show that diflunisal, an aspirin‐like nonsteroidal anti‐inflammatory drug (NSAID) that has been in clinical use for decades, specifically inhibits in vitro and in vivo the chemotactic activity of HMGB1 at nanomolar concentrations, at least in part by binding directly to both HMGB1 and CXCL12 and disrupting their heterocomplex. Importantly, diflunisal does not inhibit TLR4‐dependent responses. Our findings clarify the mode of action of diflunisal and open the way to the rational design of functionally specific anti‐inflammatory drugs.