Docking Strategy To Construct Thermostable, Single-Crystalline, Hydrogen-Bonded Organic Framework with High Surface Area

Enhancing thermal and chemical durability and increasing surface area are two main directions for the construction and improvement of the performance of porous hydrogen-bonded organic frameworks (HOFs). Herein, a hexaazatriphenylene (HAT) derivative that possesses six carboxyaryl groups serves as a suitable building block for the systematic construction of thermally and chemically durable HOFs with high surface area through shape-fitted docking between the HAT cores and interpenetrated three-dimensional network. A HAT derivative with carboxybiphenyl groups forms a stable single-crystalline porous HOF that displays protic solvent durability, even in concentrated HCl, heat resistance up to 305 °C, and a high Brunauer–Emmett–Teller surface area [SA(BET)] of 1288 m2 g−1. A single crystal of this HOF displays anisotropic fluorescence, which suggests that it would be applicable to polarized emitters based on robust functional porous materials.This is the accepted version of the following article: Hisaki I., Suzuki Y., Gomez E., et al. Docking Strategy To Construct Thermostable, Single-Crystalline, Hydrogen-Bonded Organic Framework with High Surface Area. Angewandte Chemie - International Edition 57, 12650 (2018), which has been published in final form at https://doi.org/10.1002/anie.201805472. This article may be used for non-commercialpurposes in accordance with the Wiley Self-ArchivingPolicy [https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.html

Thiophene-Based Covalent Organic Frameworks: Synthesis, Photophysics and Light-Driven Applications

Porous crystalline materials, such as covalent organic frameworks (COFs), have emerged as some of the most important materials over the last two decades due to their excellent physicochemical properties such as their large surface area and permanent, accessible porosity. On the other hand, thiophene derivatives are common versatile scaffolds in organic chemistry. Their outstanding electrical properties have boosted their use in different light-driven applications (photocatalysis, organic thin film transistors, photoelectrodes, organic photovoltaics, etc.), attracting much attention in the research community. Despite the great potential of both systems, porous COF materials based on thiophene monomers are scarce due to the inappropriate angle provided by the latter, which hinders its use as the building block of the former. To circumvent this drawback, researchers have engineered a number of thiophene derivatives that can form part of the COFs structure, while keeping their intrinsic properties. Hence, in the present minireview, we will disclose some of the most relevant thiophene-based COFs, highlighting their basic components (building units), spectroscopic properties and potential light-driven applications

Hexaazatriphenylene-Based Hydrogen-Bonded Organic Framework with Permanent Porosity and Single-Crystallinity

Hydrogen-bonded organic frameworks (HOFs) have drawn unprecedented interest because of their high crystallinity as well as facile process for construction, deconstruction, and reassembly arising from reversible bond formation-dissociation. However, structural fragility and low stability frequently prevent formation of robust HOFs with permanent porosity. Here, we report that hexakis(4-carboxyphenyl)-hexaazatriphenylene (CPHAT) forms three dimensionally networked H-bonded framework CPHAT-1. Interestingly, the activated framework CPHAT-1 a retains not only permanent porosity but single-crystallinity, enabling precise structural characterization and property evaluation on a single crystal. Moreover, CPHAT-1 a retains its framework up to 339 °C or in hot water and in acidic aqueous solution. These results clearly show that even a simple H-bonding motif can be applied for the construction of robust HOFs, which creates a pathway to establish a new class of porous organic frameworks. We also characterize its uptake of gases and I2, in addition to a detailed photophysical study (spectroscopy and dynamics of proton and charge transfers) of its unit in solution, and of its single crystal under fluorescence microscopy, in which we observed a marked strong anistropy and narrow distribution. The results bring new findings to the area of HOFs and their possible applications in science and technology.This is the accepted version of the following article: Hisaki I., Ikenaka N., Gomez E., et al. Hexaazatriphenylene-Based Hydrogen-Bonded Organic Framework with Permanent Porosity and Single-Crystallinity. Chemistry - A European Journal 23, 11611 (2017), which has been published in final form at https://doi.org/10.1002/chem.201701893. This article may be used for non-commercialpurposes in accordance with the Wiley Self-ArchivingPolicy [https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.html

Unraveling Competitive Electron and Energy-Transfer Events at the Interfaces of a 2D MOF and Nile Red Composites: Effect of the Length and Structure of the Linker

[EN] The distribution and interactions of organic molecules adsorbed on the surface of materials play important roles in many catalytic and photonic processes. Here, we show that the length and chemical structure of the linker in new Al-ITQ metal-organic frameworks (MOFs) are fundamental for the dynamics of the dye Nile Red (NR) adsorbed on its surface. For the studied composites using A1-ITQ-4-ethylbenzoic acid (EB), Al-ITQ-4-aminobenzoic acid (AB), and Al-ITQ : EB exposed to the aniline (AN) or N,N-dimethylani-line (DMA) atmospheres, we observed a very fast (similar to 1.2 ps) intramolecular charge-transfer reaction in adsorbed NR molecules. For NR@Al-ITQEB, where the linker has a shorter aliphatic chain (two carbons), the dye molecules present a homoenergy-transfer (ET) process, which is faster (similar to 90 ps) than in the previously reported NR@Al-ITQ-4-heptylbenzoic acid composite with longer aliphatic chain (seven carbons, similar to 220 ps). The more polar environment created by the Al-oxide nodes in Al-ITQ-EB surface around the NR populations strongly favors the ET event. When the linker structure contains phenyl amine moieties, the resulting NR@Al-ITQ-AB composites show different and rich photodynamics, in which a fast electron transfer reaction from the MOF aniline moiety to the adsorbed NR occurs in similar to 17 ps, inhibiting the ET process between the dye molecules near the MOF surface. This process also was confirmed in Al-ITQ-EB MOF exposed to AN and DMA gas atmospheres, as well as NR in pure aniline. The obtained results demonstrate how modifications in the length and structure of the organic linker in this MOF change the interface interactions and outcome of the photoinduced processes in the composites. Our findings on dye-MOF interface photobehavior are relevant to the design of new materials in which the interface plays a key role in their performance in the fields of catalysis and photonics.This work was supported by MINECO through projects MAT2014-57646-P, MAT2017-86532-R, and MAT2017-82288-C2-1-P. J.M.M. thanks the predoctoral fellowship from the Severo Ochoa program for support (SEV-2016-0683), and E.C.-M thanks the MINECO for the FPI fellowship (BES-2015-071495). We thank Dr. John Spencer Baskin for reading the manuscript.Caballero-Mancebo, E.; Moreno-Rodríguez, JM.; Cohen, B.; Díaz Morales, UM.; Corma Canós, A.; Douhal, A. (2018). Unraveling Competitive Electron and Energy-Transfer Events at the Interfaces of a 2D MOF and Nile Red Composites: Effect of the Length and Structure of the Linker. ACS Applied Materials & Interfaces. 10(38):32885-32894. https://doi.org/10.1021/acsami.8b12188S3288532894103

Femto-to nanosecond photodynamics of Nile Red in metal-ion exchanged faujasites

[EN] We report on the photodynamics of Nile Red (NR) interacting with faujasite (NaY)-type zeolites having different Na/Al ratios and charge balancing metals (Li+, Mg2+, and Cs+) in dichloromethane (DCM) suspensions. The encapsulation of NR in these materials leads to the formation of different populations, reflected in H- and J-aggregates, monomers, and surface adsorbed species. Due to the interaction of the dye with both the Bronsted and Lewis sites of the zeolite, a bathochromic shift is observed in the steady-state diffuse transmittance and emission spectra. The relative contribution of each population is affected by the Na/Al ratio and the nature of the doping metal ion. These findings are further explored by femtoto nanosecond time-resolved emission experiments, where a multi-exponential behaviour is observed for the excited samples. The fluorescence lifetimes range from similar to 100 ps to similar to 2 ns. They are assigned to the emission from H- and J-aggregates and monomers. At low Na/Al ratios, we observed an increase in the fluorescence time constants which is explained in terms of H-bonds formation between NR and the zeolite framework, while the change in the emission lifetimes for the metal ion exchanged zeolites is due to the variation of the properties (size and polarization ability) of the exchanged cation. An ultrafast formation (similar to 200 fs) of a charge-separated state (CS) followed by a vibrational cooling (similar to 1-2 ps) are observed in the fluorescence up-conversion transients. These results indicate a strong interaction between NR and the studied zeolites and may help for the design of metal ion sensors and for a better understanding of nanocatalysis. (C) 2017 Elsevier Inc. All rights reserved.This work was supported by the JCCM and MINECO through projects: PEII-2014-003-P, Consolider Ingenio 2010 (CSD2009-0050, MULTICAT), and MAT2014-57646-P. A. Corma and M.T. Navarro thank the MINECO (Severo Ochoa program SEV-2012-0267 and MAT2015-71842-P) for financial support.Di Nunzio, MR.; Caballero-Mancebo, E.; Martin, C.; Cohen, B.; Navarro Villalba, MT.; Corma Canós, A.; Douhal, A. (2018). Femto-to nanosecond photodynamics of Nile Red in metal-ion exchanged faujasites. Microporous and Mesoporous Materials. 256:214-226. https://doi.org/10.1016/j.micromeso.2017.08.011S21422625

Facile Synthesis, Characterization, and Deciphering of Their Ultrafast-to-Slow Photodynamics

InP-based quantum dots (QDs) are an environment-friendly alternative to their heavy metal-ion-based counterparts. Herein we report a simple procedure for synthesizing blue emissive InP QDs using oleic acid and oleylamine as surface ligands, yielding ultrasmall QDs with average sizes of 1.74 and 1.81 nm, respectively. Consecutive thin coating with ZnS increased the size of these QDs to 4.11 and 4.15 nm, respectively, alongside a significant enhancement of their emission intensities centered at ∼410 nm and ∼430 nm, respectively. Pure phase synthesis of these deep-blue emissive QDs is confirmed by powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Armed with femtosecond to millisecond time-resolved spectroscopic techniques, we decipher the energy pathways, reflecting the effect of successive ZnS passivation on the charge carrier (electrons and holes) dynamics in the deep-blue emissive InP, InP/ZnS, and InP/ZnS/ ZnS QDs. Successive coating of the InP QDs increases the intraband relaxation times from 200 to 700 fs and the lifetime of the hot electrons from 2 to 8 ps. The lifetime of the cold holes also increase from 1 to 4 ps, and remarkably, the Auger recombination escalates from 15 to 165 ps. The coating also drastically decreases the quenching by the molecular oxygen of the trapped charge carriers at the surfaces of the QDs. Our results provide clues to push further the emission of InP QDs into more energetically spectral regions and to increase the fluorescence quantum yield, targeting the construction of efficient UV-emissive light-emitting devices (LEDs)

Association between 8 P-glycoprotein (MDR1/ABCB1) gene polymorphisms and antipsychotic drug-induced hyperprolactinaemia

INTRODUCTION: Hyperprolactinaemia, a common adverse effect of antipsychotic drugs, is primarily linked to blockade of dopamine D2 receptors in the pituitary gland. Certain antipsychotic drugs, such as, for example risperidone and paliperidone, are more likely to induce hyperprolactinaemia compared to others. This effect is probably caused by a relatively high blood/brain concentration ratio, a consequence of being a substrate of P-glycoprotein. Genetic variants of P-glycoprotein with changed functional activity might influence the potential of risperidone and paliperidone to cause hyperprolactinaemia as the altered blood/brain concentration ratio would lead to a reduced therapeutic drug level within essential brain areas making dose adaptations necessary. This increases exposure of dopamine D2 receptors within the pituitary gland. AIMS: To investigate possible associations between MDR1/ABCB1 gene polymorphisms and antipsychotic drug-induced hyperprolactinaemia in Russian patients with schizophrenia and to determine possible differences between risperidone/paliperidone and other antipsychotics. METHODS: In total, 446 patients with schizophrenia were included from 3 psychiatric hospitals in Siberia. Blood samples were obtained in a cross-sectional study design for DNA extraction and prolactin measurement. Associations between hyperprolactinaemia and 8 MDR1/ABCB1 gene-polymorphisms were assessed using logistic regression analysis accounting for covariates. The analysis was repeated in a patient subgroup using risperidone or paliperidone. RESULTS: We did not observe an association between any of the 8 single nucleotide polymorphisms and the prevalence of antipsychotic-induced hyperprolactinaemia in the total patient population. However, in the risperidone/paliperidone subgroup, the single nucleotide polymorphism rs2032582 (G2677T) was found to be negatively associated with risperidone/paliperidone-induced hyperprolactinaemia. CONCLUSION: This study revealed a significant association between the ABCB1 gene polymorphism rs2032582 (G2677T) and risperidone/paliperidone-induced hyperprolactinaemia

Test–retest stability of patient experience items derived from the national GP patient survey

PURPOSE: The validity and reliability of various items on the GP Patient Survey (GPPS) survey have been reported, however stability of patient responses over time has not been tested. The purpose of this study was to determine the test-retest reliability of the core items from the GPPS. METHODS: Patients who had recently consulted participating GPs in five general practices across the South West England were sent a postal questionnaire comprising of 54 items concerning their experience of their consultation and the care they received from the GP practice. Patients returning the questionnaire within 3 weeks of mail-out were sent a second identical (retest) questionnaire. Stability of responses was assessed by raw agreement rates and Cohen's kappa (for categorical response items) and intraclass correlation coefficients and means (for ordinal response items). RESULTS: 348 of 597 Patients returned a retest questionnaire (58.3 % response rate). In comparison to the test phase, patients responding to the retest phase were older and more likely to have white British ethnicity. Raw agreement rates for the 33 categorical items ranged from 66 to 100 % (mean 88 %) while the kappa coefficients ranged from 0.00 to 1.00 (mean 0.53). Intraclass correlation coefficients for the 21 ordinal items averaged 0.67 (range 0.44-0.77). CONCLUSIONS: Formal testing of items from the national GP patient survey examining patient experience in primary care highlighted their acceptable temporal stability several weeks following a GP consultation.Funding was provided by Health Services and Delivery Research Programme (Grant No. RP-PG-0608-10050)

Association between 8 P-glycoprotein (MDR1/ABCB1) gene polymorphisms and antipsychotic drug-induced hyperprolactinaemia

Introduction: Hyperprolactinaemia, a common adverse effect of antipsychotic drugs, is primarily linked to blockade of dopamine D2 receptors in the pituitary gland. Certain antipsychotic drugs, such as, for example risperidone and paliperidone, are more likely to induce hyperprolactinaemia compared to others. This effect is probably caused by a relatively high blood/brain concentration ratio, a consequence of being a substrate of P-glycoprotein. Genetic variants of P-glycoprotein with changed functional activity might influence the potential of risperidone and paliperidone to cause hyperprolactinaemia as the altered blood/brain concentration ratio would lead to a reduced therapeutic drug level within essential brain areas making dose adaptations necessary. This increases exposure of dopamine D2 receptors within the pituitary gland. Aims: To investigate possible associations between MDR1/ABCB1 gene polymorphisms and antipsychotic drug-induced hyperprolactinaemia in Russian patients with schizophrenia and to determine possible differences between risperidone/paliperidone and other antipsychotics. Methods: In total, 446 patients with schizophrenia were included from 3 psychiatric hospitals in Siberia. Blood samples were obtained in a cross-sectional study design for DNA extraction and prolactin measurement. Associations between hyperprolactinaemia and 8 MDR1/ABCB1 gene-polymorphisms were assessed using logistic regression analysis accounting for covariates. The analysis was repeated in a patient subgroup using risperidone or paliperidone. Results: We did not observe an association between any of the 8 single nucleotide polymorphisms and the prevalence of antipsychotic-induced hyperprolactinaemia in the total patient population. However, in the risperidone/paliperidone subgroup, the single nucleotide polymorphism rs2032582 (G2677T) was found to be negatively associated with risperidone/paliperidone-induced hyperprolactinaemia. Conclusion: This study revealed a significant association between the ABCB1 gene polymorphism rs2032582 (G2677T) and risperidone/paliperidone-induced hyperprolactinaemia

LOFAR MSSS: Detection of a low-frequency radio transient in 400 hrs of monitoring of the North Celestial Pole

We present the results of a four-month campaign searching for low-frequency radio transients near the North Celestial Pole with the Low-Frequency Array (LOFAR), as part of the Multifrequency Snapshot Sky Survey (MSSS). The data were recorded between 2011 December and 2012 April and comprised 2149 11-minute snapshots, each covering 175 deg^2. We have found one convincing candidate astrophysical transient, with a duration of a few minutes and a flux density at 60 MHz of 15-25 Jy. The transient does not repeat and has no obvious optical or high-energy counterpart, as a result of which its nature is unclear. The detection of this event implies a transient rate at 60 MHz of 3.9 (+14.7, -3.7) x 10^-4 day^-1 deg^-2, and a transient surface density of 1.5 x 10^-5 deg^-2, at a 7.9-Jy limiting flux density and ~10-minute time-scale. The campaign data were also searched for transients at a range of other time-scales, from 0.5 to 297 min, which allowed us to place a range of limits on transient rates at 60 MHz as a function of observation duration.Peer reviewedFinal Accepted Versio