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Different approaches to achieve 2D supramolecular polymers, as an alternative to the covalent bottom‐up approaches reported for the preparation of 2D materials, are reviewed. The significance of the operation of weak non‐covalent forces to induce a lateral growth of a number of self‐assembling units is collected. The examples of both thermodynamically and kinetically controlled formation of 2D supramolecular polymers showed in this review demonstrate the utility of this strategy to achieve new 2D materials with biased morphologies (nanosheets, scrolls, porous surfaces) and showing elegant applications like chiral recognition, enantioselective uptake or asymmetric organic transformations. Furthermore, elaborated techniques like seeded or living supramolecular polymerizations have been demonstrated to give rise to complex 2D nanostructures. [ABSTRACT FROM AUTHOR]

High myopia is the most severe and pathological form of myopia. It occurs when the spherical refractive error exceeds –6.00 spherical diopters (SDs) or the axial length (AL) of the eye is greater than 26 mm. This article focuses on early-onset high myopia, an increasingly common condition that affects children under 10 years of age and can lead to other serious ocular pathologies. Through the genetic analysis of 21 families with early-onset high myopia, this study seeks to contribute to a better understanding of the role of genetics in this disease and to propose candidate genes. Whole-exome sequencing studies with a panel of genes known to be involved in the pathology were performed in families with inconclusive results: 3% of the variants found were classified as pathogenic, 6% were likely pathogenic and the remaining 91% were variants of uncertain significance. Most of the families in this study were found to have alterations in several of the proposed genes. This suggests a polygenic inheritance of the pathology due to the cumulative effect of the alterations. Further studies are needed to validate and confirm the role of these alterations in the development of early-onset high myopia and its polygenic inheritance. [ABSTRACT FROM AUTHOR]

Keratoconus is a corneal dystrophy that is one of the main causes of corneal transplantation and for which there is currently no effective treatment for all patients. The presentation of this disease in pediatric age is associated with rapid progression, a worse prognosis and, in 15–20% of cases, the need for corneal transplantation. It is a multifactorial disease with genetic variability, which makes its genetic study difficult. Discovering new therapeutic targets is necessary to improve the quality of life of patients. In this manuscript, we present the results of whole-exome sequencing (WES) of 24 pediatric families diagnosed at the University Hospital La Paz (HULP) in Madrid. The results show an oligogenic inheritance of the disease. Genes involved in the structure, function, cell adhesion, development and repair pathways of the cornea are proposed as candidate genes for the disease. Further studies are needed to confirm the involvement of the candidate genes described in this article in the development of pediatric keratoconus. [ABSTRACT FROM AUTHOR]

Non-syndromic pediatric cataracts are defined as opacification of the crystalline lens that occurs during the first years of life without affecting other organs. Given that this disease is one of the most frequent causes of reversible blindness in childhood, the main objective of this study was to propose new responsible gene candidates that would allow a more targeted genetic approach and expand our genetic knowledge about the disease. We present a whole exome sequencing (WES) study of 20 Spanish families with non-syndromic pediatric cataracts and a previous negative result on an ophthalmology next-generation sequencing panel. After ophthalmological evaluation and collection of peripheral blood samples from these families, WES was performed. We were able to reach a genetic diagnosis in 10% of the families analyzed and found genes that could cause pediatric cataracts in 35% of the cohort. Of the variants found, 18.2% were classified as pathogenic, 9% as likely pathogenic, and 72.8% as variants of uncertain significance. However, we did not find conclusive results in 55% of the families studied, which suggests further studies are needed. The results of this WES study allow us to propose LONP1, ACACA, TRPM1, CLIC5, HSPE1, ODF1, PIKFYVE, and CHMP4A as potential candidates to further investigate for their role in pediatric cataracts, and AQP5 and locus 2q37 as causal genes. [ABSTRACT FROM AUTHOR]

A novel D-pi-A system in which tetrathiafulvalene (TTF) and pi-extended TTFs as strong electron donors are covalently connected to a tricarbonyl [eta(super 6)-arene]chromium complex as the acceptor moiety through a systematically increased conjugated bridge of vinylene units are synthesized by Wittig-Horner olefination reaction.

The synthesis of a new series of electron donor-acceptor conjugates in which the electron acceptor-[C.sub.60]-and the electron donor-[pi]-extended tetrathiafulvalene (exTTF)-are bridged by using m-phenyleneethynylene spacers of variable length is described. AFM spectroscopy is used for showing the ability of these new conjugates to form wirelike structures upon deposition onto a mica surface.

Two new tetrafullerene nanoconjugates consisting of four [C.sub.60] units that are covalently connected through different [pi]-conjugated oligomers (oligo(p-phenylene ethynylene) and oligo(p-phenylene vinylene)) were prepared. Both the nanoconjugates exhibited a very fast deactivation of the singlet excited state of the core unit that produces a mixture of a charge-separated state, involving a radical cation on the [pi]-conjugated oligomer and the fullerene anion at one of the termini.

Abstract: The development of sophisticated ordered functional materials is one of the important challenges in current science. One of the keys to enhance the properties of these materials is the control of the organization and morphology at different scales. This work presents a novel bioinspired methodology to achieve highly ordered donor/acceptor bio‐nanohybrids using a designed repeat protein as scaffold, endowed with photoactive and electron donating porphyrin (P) units, to efficiently wrap around electron accepting single wall carbon nanotubes (SWCNT). A systematic experimental and theoretical study to evaluate the effect of the length of the protein reveals that longer proteins wrap around the SWCNT in a more efficient manner due to the stronger supramolecular interaction existing between the inner concave surface of the protein (namely Trp and His residues) and the convex surface of the (7,6)‐SWCNT. Interestingly, spectroscopy and X‐ray diffraction data further confirm that the so‐called protein‐P–SWCNT donor–acceptor bio‐nanohybrids retain the original protein structure. Finally, the new bio‐nanohybrids show a remarkable enhancement on the photoconductivity values by flash‐photolysis microwave conductivity (FP‐TRMC technique) demonstrating that the major charge carriers of electrons are injected into the SWCNTs and move along the 1D‐structures. [ABSTRACT FROM AUTHOR]

Abstract: Supramolecular chemistry has evolved from the traditional focus on thermodynamic on‐pathways to the complex study of kinetic off‐pathways, which are strongly dependent on environmental conditions. Moreover, the control over pathway complexity allows nanostructures to be obtained that are inaccessible through spontaneous thermodynamic processes. Herein, we present a family of peptide‐based π‐extended tetrathiafulvalene (exTTF) molecules that show two self‐assembly pathways leading to two distinct J‐aggregates, namely metastable (M) and thermodynamic (T), with different spectroscopic, chiroptical, and electrochemical behavior. Moreover, cryo‐transmission electron microscopy (cryo‐TEM) reveals a different morphology for both aggregates and a direct observation of the morphological transformations from tapes to twisted ribbons. [ABSTRACT FROM AUTHOR]

Mesoscopic super-helices with preferred helicity have been serendipitously formed from the self-assembly of electroactive extended core discotic molecules. The investigation at dilute concentrations reveals intramolecular hydrogen-bonding and π–π stacking interactions as the driving force of the chiral self-assembly at different length scales. [ABSTRACT FROM AUTHOR]

Hybrid covalent/supramolecular porphyrin-fullerene structures were synthesized as highly efficient molecular wires with a remarkably low attenuation factor ( β=0.07±0.01 Å−1). Hydrogen-bonding interactions and p-phenylene oligomers of different lengths are responsible for efficient electron transfer in the molecular wires. [ABSTRACT FROM AUTHOR]

We present charge-transfer assemblies of electron accepting, pressure-synthesized carbon nanodots (pCNDs) and an electron donating porphyrin. Amidine derivatization of the porphyrin allows for hydrogen bonding interactions with the carboxyl groups on the surface of pCNDs, which drive the formation of the assembly. Upon photoexcitation, this electron donor–acceptor supramolecular construct features ultrafast charge separation, and subsequent charge recombination in 27 ps. [ABSTRACT FROM AUTHOR]

The supramolecular organization of new fullerene derivatives endowed with peptides as biomolecular templates affords ordered nanofibers of several micrometres length based on hydrogen bonds and π–π interactions. [ABSTRACT FROM AUTHOR]

The development of synthetic methods to build complex functional systems is a central and current challenge in organic chemistry. This goal is important because supramolecular architectures of highest sophistication account for function in nature, and synthetic organic chemistry, contrary to high standards with small molecules, fails to deliver functional systems of similar complexity. In this report, we introduce a collection of fullerenes that is compatible with the construction of multicomponent charge-transfer cascades and can be placed in triple-channel architectures next to stacks of oligothiophenes and naphthalenediimides. For the creation of this collection, modern fullerene chemistry-methanofullerenes and 1,4-diarylfullerenes-is combined with classical Nierengarten-Diederich-Bingel approaches. [ABSTRACT FROM AUTHOR]

Von der Nano ‐ zur Makroskala: Die Immobilisierung eines photo ‐ und redoxaktiven 9,10 ‐ Di(1,3 ‐ dithiol ‐ 2 ‐ yliden) ‐ 9,10 ‐ dihydroanthracen ‐ basierten Dipeptids (1) auf einwandigen Kohlenstoffnanoröhren (SWCNTs) liefert eine hohe Selbstausrichtung der 1/SWCNTs (siehe Bild). Die Anordnung der 1/SWCNTs ist der Schlüssel zur Stabilisierung langlebiger, ladungsgetrennter Zustände, die sich nach Photoanregung der SWCNTs bilden. [ABSTRACT FROM AUTHOR]

Fullerenes of increasing electron deficiency are designed, synthesized and evaluated in multicomponent surface architectures to ultimately build gradients in LUMO levels with nine components over 350 meV down to −4.22 eV. [ABSTRACT FROM AUTHOR]

Currently, there is a broad interest in the control over creating ordered electroactive nanostructures, in which electron donors and acceptors are organized at similar length scales. In this article, a simple and efficient procedure is reported en-route towards the construction of 1D arrays of crystalline pristine C60 and phenyl-C61-butyric acid methyl ester (PCBM) coated onto supramolecular fibers based on exTTF-pentapeptides. The resulting n/p-nanohybrids have been fully characterized by a variety of spectroscopic (FTIR, UV-Vis, circular dichroism, Raman and transient absorption), microscopic (AFM, TEM, and SEM), and powder diffraction (X-ray) techniques. Our experimental findings document the tendency of electroactive exTTF-fibers to induce the crystallization of C60 and PCBM, on one hand, and to afford 1D n/p-nanohybrids, on the other hand. Furthermore, photogenerated radical ion pairs, formed upon visible light irradiation of the n/p-nanohybrids, feature lifetimes on the range of 0.9-1.2 ns. [ABSTRACT FROM AUTHOR]

Supramolecular chemistry has evolved from the traditional focus on thermodynamic on-pathways to the complex study of kinetic off-pathways, which are strongly dependent on environmental conditions. Moreover, the control over pathway complexity allows nanostructures to be obtained that are inaccessible through spontaneous thermodynamic processes. Herein, we present a family of peptide-based π-extended tetrathiafulvalene (exTTF) molecules that show two self-assembly pathways leading to two distinct J-aggregates, namely metastable (M) and thermodynamic (T), with different spectroscopic, chiroptical, and electrochemical behavior. Moreover, cryo-transmission electron microscopy (cryo-TEM) reveals a different morphology for both aggregates and a direct observation of the morphological transformations from tapes to twisted ribbons., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Rigid and soluble electron donor-acceptor conjugates combining exTTF and/or TTF as donors and C60 as acceptor have been synthesized; fluorescence and transient absorption measurements confirm the generation of charge-separated radical-ion pairs with lifetimes in the micros timescale.

This tutorial review surveys and highlights the integration of different molecular wires-in combination with chromophores that exhibit (i) significant absorption cross section throughout the visible part of the solar spectrum and (ii) good electron donating power-into novel electron donor-acceptor conjugates. The focus is predominantly on charge transfer and charge transport features of the most promising systems.

An extensive study by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) of some first-generation and second-generation lanthanide(III)-cored poly(phenylenevinylene) dendrimers is described. The complexes were obtained by self-assembly of suitably functionalized carboxylate dendrons around the lanthanide ion (La(3+), Er(3+)). Fourier transform infrared (FT-IR) spectroscopy gave reasonable evidence for the proposed structures. However, MS was used to ascertain unequivocally the complex formation. The most reliable results were found in the negative reflector mode, using 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene]malononitrile (DCTB) as matrix. Well-defined and highly resolved base peaks corresponding to negative ions of [Gn(4)La](-) and [Gn(4)Er](-) were found in all cases, with an excellent match between the theoretical and observed isotope distributions. However, the 3:1 stoichiometry used in the synthesis guarantees an empirical formula Gn(3)Ln for the complexes., (2008 John Wiley & Sons, Ltd.)

A series of donor-acceptor arrays (exTTF-oPPE-C60) containing pi-conjugated oligo(phenyleneethynylene) wires (oPPE) of different length between pi-extended tetrathiafulvalene (exTTF) as electron donor and fullerene (C60) as electron acceptor has been prepared by following a convergent synthesis. The key reaction in these approaches is the bromo-iodo selectivity of the Hagihara-Sonogashira reaction and the deprotecting of acetylenes with different silyl groups to afford the corresponding donor-acceptor conjugates in moderate yields. The electronic interactions between the three electroactive species were determined by using UV-visible spectroscopy and cyclic voltammetry. Our studies clearly confirm that, although the C60 units are connected to the exTTF donor through pi-conjugated oPPE frameworks, no significant electronic interactions are observed in the ground state. Theoretical calculations predict how a simple exchange from C=C double bonds (i.e., oligo(p-phenylenevinylene) to C triple chemical bond C triple bonds (i.e., oPPE) in the electron donor-acceptor conjugates considerably alters long-range electron transfer. Photoexcitation of exTTF-oPPE-C60 leads to the following features: a transient photoproduct with maxima at 660 and 1000 nm, which are unambiguously attributed to the photolytically generated radical-ion-pair state, [exTTF*+-oPPE-C60*]. Both charge-separation and charge-recombination processes give rise to a molecular-wire behaviour of the oPPE moiety with an attenuation factor (beta) of (0.2+/-0.05) A(-1).

Weak wire-like behavior-with a damping factor (beta) of 0.2 +/- 0.05 A(-1)--has been found in a series of C60-wire-exTTF systems (i.e., p-phenyleneethynylene): these results contrast with previous observations involving p-phenylenevinylene systems.