Publications by authors named "Feng Deng"

295 Publications

Tendon-inspired fibers from liquid crystalline collagen as the pre-oriented bioink.

Int J Biol Macromol 2021 Jul 1;185:739-749. Epub 2021 Jul 1.

College of Materials Engineering, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China; National Forestry & Grassland Administration Key Laboratory for Plant Fiber Functional Materials, PR China. Electronic address:

Nature provides rich bionic resources for the construction of advanced materials with excellent mechanical properties. In this work, inspired by animal tendons, a bionic collagen fiber was developed using collagen liquid crystals as the pre-oriented bioink. The texture of liquid crystalline collagen observed from polarized optical microscopy (POM) showed the specific molecular pre-orientation. Meanwhile, the collagen spinning liquids exhibited a minimal rise in viscosity upon increasing concentration from 60 to 120 mg/mL, indicating the feasible processability. The collagen fiber, which was prepared via wet spinning without being denatured, exhibited the favorable orientation of fibrils along its axis as observed with FESEM and AFM. Thanks to the synergistic effects between pre-orientation and shearing orientation, the maximum tensile strength and Young's modulus of collagen fibers reached 9.98 cN/tex (219.29 ± 22.92 MPa) and 43.95 ± 1.11 cN/tex (966.20 ± 24.30 MPa), respectively, which were also analogous to those of tendon. In addition, the collagen fiber possessed a desirable wet strength. Benefiting from the natural tissue affinity of collagen, the as-prepared bionic collagen fiber possessed excellent wound suture performance and biodegradability in vivo, which offers a new perspective for the potential of widespread applications of collagen fibers in biomedical fields.
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http://dx.doi.org/10.1016/j.ijbiomac.2021.06.173DOI Listing
July 2021

Comparative hepatic and intestinal efflux transport of statins.

Drug Metab Dispos 2021 Jun 23. Epub 2021 Jun 23.

Department of Clinical Pharmacology, University of Helsinki, Finland

Previous studies have shown that lipid-lowering statins are transported by various ATP-binding cassette (ABC) transporters. However, due to varying methods, it is difficult to compare the transport profiles of statins. Therefore, we investigated the transport of ten statins or statin metabolites by six ABC transporters using human embryonic kidney cell-derived membrane vesicles. The transporter protein expression levels in the vesicles were quantified with liquid chromatography-tandem mass spectrometry, and used to scale the measured clearances to tissue levels. In our study, apically expressed breast cancer resistance protein (BCRP) and P-glycoprotein (P-gp) transported atorvastatin, fluvastatin, pitavastatin, and rosuvastatin. Multidrug resistance-associated protein 3 (MRP3) transported atorvastatin, fluvastatin, pitavastatin, and to a smaller extent, pravastatin. MRP4 transported fluvastatin and rosuvastatin. The scaled clearances suggest that BCRP contributes to 84-90% and 82% of the total active efflux of rosuvastatin in the small intestine and the liver, respectively. For atorvastatin, the corresponding values for P-gp-mediated efflux were 32-73% and 56%, respectively. MRP3, on the other hand, may contribute to 33-38% and 35-51% of total active efflux of atorvastatin, fluvastatin, and pitavastatin in jejunal enterocytes and liver hepatocytes, respectively. These data indicate that BCRP may play an important role in limiting the intestinal absorption and facilitating the biliary excretion of rosuvastatin and that P-gp may restrict the intestinal absorption and mediate the biliary excretion of atorvastatin. Moreover, the basolateral MRP3 may enhance the intestinal absorption and sinusoidal hepatic efflux of several statins. Taken together, the data show that statins differ considerably in their efflux transport profiles. This study characterized and compared the transport of atorvastatin, fluvastatin, pitavastatin, pravastatin, rosuvastatin, and simvastatin acid, and four atorvastatin metabolites by six ABC transporters (BCRP, MRP2, MRP3, MRP4, MRP8, P-gp). Based on findings and protein abundance data, we conclude that BCRP, MRP3 and P-gp have a major impact in the efflux of various statins. Together with metabolism, uptake transport and clinical data, our findings are applicable for use in comparative systems pharmacology modelling of statins.
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http://dx.doi.org/10.1124/dmd.121.000430DOI Listing
June 2021

Solid-state NMR studies of internuclear correlations for characterizing catalytic materials.

Chem Soc Rev 2021 Jun 11. Epub 2021 Jun 11.

National Centre for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China. and University of Chinese Academy of Sciences, Beijing 100049, China.

Understanding the nature of heterogeneous catalysts is critical for the rational design of highly active catalysts, which necessitates in-depth characterization of the structure and properties of catalysts as well as reaction mechanisms. Solid-state NMR correlation spectroscopy is becoming increasingly recognized as a powerful tool in the study of catalysts and catalytic reactions because of its capability to provide atomic-level insights into the structure, interaction and dynamics of molecules by establishing connectivity and proximity between the same or distinct nuclei. This tutorial review focuses on the fundamentals and state-of-the-art applications of solid-state NMR correlation techniques to structural characterization of catalytic materials including zeolites, metal oxides, organometallic complexes and MOFs as well as relevant studies regarding synthesis, synergistic catalysis, host-guest interactions and reaction mechanisms. Various correlation NMR methods that have been employed to address the challenging issues in heterogeneous catalysis are highlighted. This review concludes with outlooks on the promising applications and potential developments of solid-state NMR correlation spectroscopy in catalytic materials.
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http://dx.doi.org/10.1039/d0cs01130dDOI Listing
June 2021

Host-Guest Interaction in Ethylene and Ethane Separation on Zeolitic Imidazolate Frameworks as Revealed by Solid-State NMR Spectroscopy.

Chemistry 2021 Jun 10. Epub 2021 Jun 10.

State Key Laboratory of Magnetic Resonance, and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement, Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.

The separation of ethane/ethylene mixture by using metal-organic frameworks (MOFs) as adsorbents is strongly associated with the pore size-sieving effect and the adsorbent-adsorbate interaction. Herein, solid-state NMR spectroscopy is utilized to explore the host-guest interaction and ethane/ethylene separation mechanism on zeolitic imidazolate frameworks (ZIFs). Preferential access to the ZIF-8 and ZIF-8-90 frameworks by ethane compared to ethylene is directly visualized from two-dimensional H- H spin diffusion MAS NMR spectroscopy and further verified by computational density distributions. The H MAS NMR spectroscopy provides an alternative for straightforwardly extracting the adsorption selectivity of ethane/ethylene mixture at 1.1∼9.6 bar in ZIFs, which is consistent with the IAST predictions.
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http://dx.doi.org/10.1002/chem.202101779DOI Listing
June 2021

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Drug Metab Dispos 2021 May 27. Epub 2021 May 27.

Department of Clinical Pharmacology, University of Helsinki, Finland

This study aimed to comprehensively investigate the metabolism of statins. The metabolism of clinically relevant concentrations of atorvastatin, fluvastatin, pitavastatin, pravastatin, rosuvastatin, simvastatin and their metabolites were investigated using human liver microsomes (HLMs), intestine microsomes (HIMs), liver cytosol, and recombinant cytochrome P450 (CYP) enzymes. We also determined the inhibitory effects of statin acids on their pharmacological target, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase. In HLMs, statin lactones were metabolized to a much higher extent than their acid forms. Atorvastatin lactone and simvastatin (lactone) showed extensive metabolism (intrinsic clearance (CL) values of 3,700 and 7,400 µl/min/mg), while the metabolism of the lactones of 2-hydroxyatorvastatin, 4-hydroxyatorvastatin, and pitavastatin was slower (CL 20-840 µl/min/mg). The acids had CL values in the range <0.1-80 µl/min/mg. In HIMs, only atorvastatin lactone and simvastatin (lactone) exhibited notable metabolism, with CL values corresponding to 20% of those observed in HLMs. CYP3A4/5 and CYP2C9 were the main statin-metabolizing enzymes. The majority of the acids inhibited HMG-CoA reductase with 50% inhibitory concentrations of 4-20 nM. The present comparison of the metabolism and pharmacodynamics of the various statins using identical methods provides a strong basis for further application, e.g., comparative systems pharmacology modelling. The present comparison of the metabolic and pharmacodynamic properties of atorvastatin, fluvastatin, pitavastatin, pravastatin, rosuvastatin, and simvastatin and their metabolites using unified methodology provides a strong basis for further application. Together with drug transporter and clinical data, our findings are applicable for use in comparative systems pharmacology modelling to predict the pharmacokinetics and pharmacological effects of statins at different dosages.
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http://dx.doi.org/10.1124/dmd.121.000406DOI Listing
May 2021

The TiO-μ implant residual is more toxic than the AlO-n implant residual blocking LAP and inducing macrophage polarization.

Nanoscale 2021 May;13(19):8976-8990

Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, College of Stomatology, Chongqing Medical University, China. and Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, College of Stomatology, Chongqing Medical University, China and Department of Orthodontics, College of Stomatology, Chongqing Medical University, Chongqing, China.

Medical device residuals cause harmful effects and diseases in the human body, such as Particle Disease (PD), but the biological interaction of different types of particles is unclear. In this study, after a biological interaction screen between different particles, we aimed to explore the mechanism of the biological interaction between different types of particles, and the effect of a proteasome inhibitor on PD. Our studies showed that the titanium oxide microscale particle (Ti-μ) was more toxic than the aluminum oxide nanoscale particle (Al-n). Al-n activated LAP, attenuated the macrophage M1 polarization, inhibited the activator of the NF-κB pathway, and blocked the secretion of inflammatory factors and apoptosis in vitro, and also prevented the inflammation tissue disorder and aseptic loosening in vivo induced by Ti-μ. What is more, Bortezomib blocked apoptosis, secretion of inflammatory factors and the activation of the NF-κB pathway induced by TiO2 micro particles. Al-n-induced autophagy could play the function in the efficient clearance of dying cells by phagocytosis, and serves in dampening M1 polarization-related pro-inflammatory responses. While the Ti alloy medical implant and devices are applied worldwide, the toxicity of Ti-μ and its interaction with Al-n could be considered in the implant design, and Bortezomib was a potential therapeutic for PD.
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http://dx.doi.org/10.1039/d1nr00696gDOI Listing
May 2021

Through-space B- Al correlation: Influence of the recoupling channel.

Magn Reson Chem 2021 Apr 13. Epub 2021 Apr 13.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Centre for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.

Through-space heteronuclear correlation (D-HETCOR) experiments based on heteronuclear multiple-quantum correlation (D-HMQC) and refocused insensitive nuclei enhanced by polarization transfer (D-RINEPT) sequences have been proven to be useful approaches for the detection of the spatial proximity between half-integer quadrupolar nuclei in solids under magic-angle spinning (MAS) conditions. The corresponding pulse sequences employ coherence transfers mediated by heteronuclear dipolar interactions, which are reintroduced under MAS by radiofrequency irradiation of only one of the two correlated nuclei. We investigate herein using numerical simulations of spin dynamics and solid-state NMR experiments on magnesium aluminoborate glass how the choice of the channel to which the heteronuclear dipolar recoupling is applied affects the transfer efficiency of D-HMQC and D-RINEPT sequences between B and Al nuclei. Experimental results show that maximum transfer efficiency is achieved when the recoupling scheme is applied to the channel, for which the spin magnetization is parallel to the B axis in average.
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http://dx.doi.org/10.1002/mrc.5163DOI Listing
April 2021

Dual Active Sites on Molybdenum/ZSM-5 Catalyst for Methane Dehydroaromatization: Insights from Solid-State NMR Spectroscopy.

Angew Chem Int Ed Engl 2021 May 6;60(19):10709-10715. Epub 2021 Apr 6.

National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.

Methane dehydroaromatization (MDA) on Mo/ZSM-5 zeolite catalyst is promising for direct transformation of natural gas. Understanding the nature of active sites on Mo/ZSM-5 is a challenge for applications. Herein, using H{ Mo} double-resonance solid-state NMR spectroscopy, we identify proximate dual active sites on Mo/ZSM-5 catalyst by direct observation of internuclear spatial interaction between Brønsted acid site and Mo species in zeolite channels. The acidic proton-Mo spatial interaction is correlated with methane conversion and aromatics formation in the MDA process, an important factor in determining the catalyst activity and lifetime. The evolution of olefins and aromatics in Mo/ZSM-5 channels is monitored by detecting their host-guest interactions with both active Mo sites and Brønsted acid sites via H{ Mo} double-resonance and two-dimensional H- H correlation NMR spectroscopy, revealing the intermediate role of olefins in hydrocarbon pool process during the MDA reaction.
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http://dx.doi.org/10.1002/anie.202017074DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8284829PMC
May 2021

The SNAG Domain of Insm1 Regulates Pancreatic Endocrine Cell Differentiation and Represses β- to δ-Cell Transdifferentiation.

Diabetes 2021 May 5;70(5):1084-1097. Epub 2021 Feb 5.

The First Affiliated Hospital of Jinan University, Guangzhou, China

The allocation and specification of pancreatic endocrine lineages are tightly regulated by transcription factors. Disturbances in differentiation of these lineages contribute to the development of various metabolic diseases, including diabetes. The insulinoma-associated protein 1 (), which encodes a protein containing one SNAG domain and five zinc fingers, plays essential roles in pancreatic endocrine cell differentiation and in mature β-cell function. In the current study, we compared the differentiation of pancreatic endocrine cells between Insm1 null and Insm1 SNAG domain mutants (Insm1delSNAG) to explore the specific function of the SNAG domain of Insm1. We show that the δ-cell number is increased in Insm1delSNAG but not in Insm1 null mutants as compared with the control mice. We also show a less severe reduction of the β-cell number in Insm1delSNAG as that in Insm1 null mutants. In addition, similar deficits are observed in α-, PP, and ε-cells in Insm1delSNAG and Insm1 null mutants. We further identified that the increased δ-cell number is due to β- to δ-cell transdifferentiation. Mechanistically, the SNAG domain of Insm1 interacts with Lsd1, the demethylase of H3K4me1/2. Mutation in the SNAG domain of Insm1 results in impaired recruitment of Lsd1 and increased H3K4me1/2 levels at hematopoietically expressed homeobox () loci that are bound by Insm1, thereby promoting the transcriptional activity of the δ-cell-specific gene Our study has identified a novel function of the SNAG domain of Insm1 in the regulation of pancreatic endocrine cell differentiation, particularly in the repression of β- to δ-cell transdifferentiation.
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http://dx.doi.org/10.2337/db20-0883DOI Listing
May 2021

Removal of ammonia nitrogen and phosphorus by biochar prepared from sludge residue after rusty scrap iron and reduced iron powder enhanced fermentation.

J Environ Manage 2021 Mar 12;282:111970. Epub 2021 Jan 12.

Environmental Science and Engineering College, Nanjing Tech University, Nanjing, 211816, China.

The rusty scrap iron (RSI) or a mixture of rusty scrap iron and reduced iron powder (RSI-RIP) can be used as an exogenous additive to enhance the anaerobic fermentation of sewage sludge. In order to make rational use of the fermentation residue, the sludge after intensified fermentation was pyrolyzed to produce biochar in this study, which was used in the adsorption of ammonia and phosphorus from the anaerobic fermentation broth. The experimental results demonstrated that the pore structure of the sludge biochar was greatly improved after enhanced fermentation with RSI and RIP. Meanwhile, there was an increase in the proportion of metallic elements such as Ca, Fe and Mg. On the other hand, the RSI-RIP co-enhanced fermented biochar (ES600) prepared at 600 °C showed a higher adsorption capacity, which was comparable to the commercially activated carbon. Neutral or weakly alkaline environments were preferred during the adsorption process. At a suitable pH condition, the maximum removal efficiency of ammonia nitrogen (NH-N) and total phosphorus (TP) on ES600 reached 91.3% and 98.6%, respectively. In addition, the saturated ES600 was regenerated by simple washing with ammonia-free water. After three cycles, the removal efficiency of NH-N and TP remained at 71.3% and 83.2%, respectively. As a result, the biochar prepared from RSI-RIP enhanced fermented sludge can be used as a promising low-cost adsorbent.
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http://dx.doi.org/10.1016/j.jenvman.2021.111970DOI Listing
March 2021

Solid-state P NMR mapping of active centers and relevant spatial correlations in solid acid catalysts.

Nat Protoc 2020 10 23;15(10):3527-3555. Epub 2020 Sep 23.

State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, P. R. China.

Solid acid catalysts are used extensively in various advanced chemical and petrochemical processes. Their catalytic performance (namely, activity, selectivity, and reaction pathway) mostly depends on their acid properties, such as type (Brønsted versus Lewis), location, concentration, and strength, as well as the spatial correlations of their acid sites. Among the diverse methods available for acidity characterization, solid-state nuclear magnetic resonance (SSNMR) techniques have been recognized as the most valuable and reliable tool, especially in conjunction with suitable probe molecules that possess observable nuclei with desirable properties. Taking P probe molecules as an example, both trimethylphosphine (TMP) and trimethylphosphine oxide (TMPO) adsorb preferentially to the acid sites on solid catalysts and thus are capable of providing qualitative and quantitative information for both Brønsted and Lewis acid sites. This protocol describes procedures for (i) the pretreatment of typical solid acid catalysts, (ii) adoption and adsorption of various P probe molecules, (iii) considerations for one- and two-dimensional (1D and 2D, respectively) NMR acquisition, (iv) relevant data analysis and spectral assignment, and (v) methodology for NMR mapping with the assistance of theoretical calculations. Users familiar with SSNMR experiments can complete P-H heteronuclear correlation (HETCOR), P-P proton-driven spin diffusion (PDSD), and double-quantum (DQ) homonuclear correlation with this protocol within 2-3 d, depending on the complexity and the accessible acid sites of the solid acid samples.
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http://dx.doi.org/10.1038/s41596-020-0385-6DOI Listing
October 2020

Hydrogen Spillover to Oxygen Vacancy of TiOH/Fe: Breaking the Scaling Relationship of Ammonia Synthesis.

J Am Chem Soc 2020 Oct 5;142(41):17403-17412. Epub 2020 Oct 5.

Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental & Applied Chemistry, College of Chemistry, Central China Normal University, Wuhan 430079, P. R. China.

Optimizing kinetic barriers of ammonia synthesis to reduce the energy intensity has recently attracted significant research interest. The motivation for the research is to discover means by which activation barriers of N dissociation and NH ( = 1-2, surface intermediates) destabilization can be reduced simultaneously, that is, breaking the "scaling relationship". However, by far only a single success has been reported in 2016 based on the discovery of a strong-weak N-bonding pair: transition metals (nitrides)-LiH. Described herein is a second example that is counterintuitively founded upon a strong-strong N-bonding pair unveiled in a bifunctional nanoscale catalyst TiOH/Fe (where 0.02 ≤ ≤ 0.03 and 0 < < 0.03), in which hydrogen spillover (H) from Fe to cascade oxygen vacancies (O-O) results in the trapped form of O-H on the TiOH component. The Fe component thus enables facile activation of N, while the O-H in TiOH hydrogenates the N or NH to NH easily.
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http://dx.doi.org/10.1021/jacs.0c06118DOI Listing
October 2020

Recent Advances of Solid-State NMR Spectroscopy for Microporous Materials.

Adv Mater 2020 Nov 9;32(44):e2002879. Epub 2020 Sep 9.

National Centre for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.

Microporous materials have attracted a rapid growth of research interest in materials science and the multidisciplinary area because of their wide applications in catalysis, separation, ion exchange, gas storage, drug release, and sensing. A fundamental understanding of their diverse structures and properties is crucial for rational design of high-performance materials and technological applications in industry. Solid-state NMR (SSNMR), capable of providing atomic-level information on both structure and dynamics, is a powerful tool in the scientific exploration of solid materials. Here, advanced SSNMR instruments and methods for characterization of microporous materials are briefly described. The recent progress of the application of SSNMR for the investigation of microporous materials including zeolites, metal-organic frameworks, covalent organic frameworks, porous aromatic frameworks, and layered materials is discussed with representative work. The versatile SSNMR techniques provide detailed information on the local structure, dynamics, and chemical processes in the confined space of porous materials. The challenges and prospects in SSNMR study of microporous and related materials are discussed.
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http://dx.doi.org/10.1002/adma.202002879DOI Listing
November 2020

Probing the active sites for methane activation on Ga/ZSM-5 zeolites with solid-state NMR spectroscopy.

Chem Commun (Camb) 2020 Oct 9;56(80):12029-12032. Epub 2020 Sep 9.

National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China.

Ga-modified zeolites represent the most effective catalyst for catalytic transformation of light alkanes to aromatics. GaO ions and GaO clusters on Ga/ZSM-5 zeolites are probed by solid-state NMR. These two types of Ga species show strong Lewis acidity and are quantitatively correlated with the catalytic activity of Ga/ZSM-5 for methane C-H bond activation. The interaction between the surface Ga species and zeolite is characterized by using double-resonance solid-state NMR spectroscopy, which provides direct spectroscopic evidence for the location and distribution of active Ga species. These results provide new insight into the understanding of the nature and role of Ga species in Ga-modified zeolites for the conversion of light alkanes.
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http://dx.doi.org/10.1039/d0cc04298fDOI Listing
October 2020

Food Additives as Inhibitors of Intestinal Drug Transporter OATP2B1.

Mol Pharm 2020 10 9;17(10):3748-3758. Epub 2020 Sep 9.

Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland.

Food additives are compounds that are added to food and beverage to improve the taste, color, preservation, or composition. Generally, food additives are considered safe for human use due to safety evaluations conducted by food safety authorities and high safety margins applied to permitted usage levels. However, the interaction potential of food additives with simultaneously administered medication has not received much attention. Even though many food additives are poorly absorbed into systemic circulation, high concentrations could exist in the intestinal lumen, making intestinal drug transporters, such as the uptake transporter organic anion transporting polypeptide 2B1 (OATP2B1), a possible site of food additive-drug interactions. In the present work, we aimed to characterize the interaction of a selection of 25 food additives including colorants, preservatives, and sweeteners with OATP2B1 . In human embryonic kidney 293 (HEK293) cells transiently overexpressing OATP2B1 or control, uptake of dibromofluorescein was studied with and without 50 μM food additive at pH 7.4. As OATP2B1 displays substrate- and pH-dependent transport functions and the intraluminal pH varies along the gastrointestinal tract, we performed the studies also at pH 5.5 using estrone sulfate as an OATP2B1 substrate. Food additives that inhibited OATP2B1-mediated substrate transport by ≥50% were subjected to dose-response studies. Six colorants were identified and validated as OATP2B1 inhibitors at pH 5.5, but only three of these were categorized as inhibitors at pH 7.4. One sweetener was validated as an inhibitor under both assay conditions, whereas none of the preservatives exhibited ≥50% inhibition of OATP2B1-mediated transport. Extrapolation of computed inhibitory constants ( values) to estimations of intestinal food additive concentrations implies that selected colorants could inhibit intestinal OATP2B1 also . These results suggest that food additives, especially colorants, could alter the pharmacokinetics of orally administered OATP2B1 substrate drugs, although further studies are warranted to understand the overall clinical consequences of the findings.
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http://dx.doi.org/10.1021/acs.molpharmaceut.0c00507DOI Listing
October 2020

Molecular Vises for Precisely Positioning Ligands near Catalytic Metal Centers in Metal-Organic Frameworks.

J Am Chem Soc 2020 09 26;142(38):16182-16187. Epub 2020 Aug 26.

Key Laboratory of Biomedical Polymers, Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.

We report the construction of a molecular vise by pairing a tritopic phenylphosphorus(III) linker and a monotopic linker in opposite positions within a metal-organic framework. The angle between these linkers at metal sites is fixed upon changing the functionality in the monotopic linker, while the distance between them is precisely tuned. This distance within the molecular vise is accurately measured by H-P solid-state nuclear magnetic resonance spectroscopy. This unveils the impact of the distance on catalytic performance without interference from electrostatic effects or changes in the angle of the ligand, which is unprecedented in classic organometallic complexes.
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http://dx.doi.org/10.1021/jacs.0c07450DOI Listing
September 2020

Mapping the oxygen structure of γ-AlO by high-field solid-state NMR spectroscopy.

Nat Commun 2020 Jul 17;11(1):3620. Epub 2020 Jul 17.

National Centre for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.

γ-AlO is one of the most widely used catalysts or catalyst supports in numerous industrial catalytic processes. Understanding the structure of γ-AlO is essential to tuning its physicochemical property, which still remains a great challenge. We report a strategy for the observation and determination of oxygen structure of γ-AlO by using two-dimensional (2D) solid-state NMR spectroscopy at high field. 2D O double-quantum single-quantum homonuclear correlation NMR experiment is conducted at an ultra-high magnetic field of 35.2 T to reveal the spatial proximities between different oxygen species from the bulk to surface. Furthermore, 2D proton-detected H-O heteronuclear correlation NMR experiments allow for a rapid identification and differentiation of surface hydroxyl groups and (sub-)surface oxygen species. Our experimental results demonstrate a non-random distribution of oxygen species in γ-AlO.
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http://dx.doi.org/10.1038/s41467-020-17470-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7367832PMC
July 2020

A Hydrothermally Stable Irreducible Oxide-Modified Pd/MgAl O Catalyst for Methane Combustion.

Angew Chem Int Ed Engl 2020 Oct 18;59(42):18522-18526. Epub 2020 Aug 18.

CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China.

Catalytic combustion is promising in removing trace amounts of CH to address serious environmental concerns. Supported Pd-based catalysts are most effective but often suffer from low stability in applications owing to the water-vapor-induced sintering. Herein, we develop a universal strategy to prepare irreducible-oxide-modified Pd/MgAl O catalysts which show high activity and excellent stability against both hydrothemal aging at elevated temperatures and deactivation in long-term reaction under wet conditions. The addition of irreducible oxides inhibited the deep oxidation of Pd in the oxygen-rich conditions, which preserved not only the epitaxial structure but also a suitable active phase of Pd-PdO on MgAl O , thus promoting both activity and stability. This work provides new insights into the effect of metal-oxide interaction on CH combustion and offers an avenue to design hydrothermally stable and active combustion catalysts for industrial applications.
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http://dx.doi.org/10.1002/anie.202009050DOI Listing
October 2020

Synthesis of Aluminophosphate Molecular Sieves in Alkaline Media.

Chemistry 2020 Sep 7;26(50):11408-11411. Epub 2020 Aug 7.

Key Lab of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, P. R. China.

Unlike conventional aluminosilicate zeolites synthesized in alkaline media, aluminophosphate molecular sieves (AlPOs) have always been prepared under acidic conditions in the past three decades; this has been regarded as one of essential factors for synthesis, except for the case of silica-substituted analogues (SAPOs). For the first time, we demonstrate herein a simple and generalized route for synthesizing various types of aluminophosphate molecular sieves in alkaline media. A series of aluminophosphate sieves and their analogues have been prepared with different quaternary ammonium cations as structure-directing agents in this manner. The above successes have extended the systematic media from acidic or neutral to alkaline for the preparation of a series of aluminophosphate molecular sieves, which possibly open an alternative route for the synthesis of aluminophosphate molecular sieves.
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http://dx.doi.org/10.1002/chem.202001050DOI Listing
September 2020

Binding Site Interactions of Modulators of Breast Cancer Resistance Protein, Multidrug Resistance-Associated Protein 2, and P-Glycoprotein Activity.

Mol Pharm 2020 07 18;17(7):2398-2410. Epub 2020 Jun 18.

Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56, Helsinki 00014, Finland.

ATP-binding cassette (ABC)-transporters protect tissues by pumping their substrates out of the cells in many physiological barriers, such as the blood-brain barrier, intestine, liver, and kidney. These substrates include various endogenous metabolites, but, in addition, ABC transporters recognize a wide range of compounds, therefore affecting the disposition and elimination of clinically used drugs and their metabolites. Although numerous ABC-transporter inhibitors are known, the underlying mechanism of inhibition is not well characterized. The aim of this study is to deepen our understanding of transporter inhibition by studying the molecular basis of ligand recognition. In the current work, we compared the effect of 44 compounds on the active transport mediated by three ABC transporters: breast cancer resistance protein (BCRP and ABCG2), multidrug-resistance associated protein (MRP2 and ABCC2), and P-glycoprotein (P-gp and ABCB1). Eight compounds were strong inhibitors of all three transporters, while the activity of 36 compounds was transporter-specific. Of the tested compounds, 39, 25, and 11 were considered as strong inhibitors, while 1, 4, and 11 compounds were inactive against BCRP, MRP2, and P-gp, respectively. In addition, six transport-enhancing stimulators were observed for P-gp. In order to understand the observed selectivity, we compared the surface properties of binding cavities in the transporters and performed structure-activity analysis and computational docking of the compounds to known binding sites in the transmembrane domains and nucleotide-binding domains. Based on the results, the studied compounds are more likely to interact with the transmembrane domain than the nucleotide-binding domain. Additionally, the surface properties of the substrate binding site in the transmembrane domains of the three transporters were in line with the observed selectivity. Because of the high activity toward BCRP, we lacked the dynamic range needed to draw conclusions on favorable interactions; however, we identified amino acids in both P-gp and MRP2 that appear to be important for ligand recognition.
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http://dx.doi.org/10.1021/acs.molpharmaceut.0c00155DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7497665PMC
July 2020

Febuxostat, But Not Allopurinol, Markedly Raises the Plasma Concentrations of the Breast Cancer Resistance Protein Substrate Rosuvastatin.

Clin Transl Sci 2020 11 26;13(6):1236-1243. Epub 2020 May 26.

Department of Clinical Pharmacology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.

Xanthine oxidase inhibitors febuxostat and allopurinol are commonly used in the treatment of gout. Febuxostat inhibits the breast cancer resistance protein (BCRP) in vitro. Rosuvastatin is a BCRP substrate and genetic variability in BCRP markedly affects rosuvastatin pharmacokinetics. In this study, we investigated possible effects of febuxostat and allopurinol on rosuvastatin pharmacokinetics. In a randomized crossover study with 3 phases, 10 healthy volunteers ingested once daily placebo for 7 days, 300 mg allopurinol for 7 days, or placebo for 3 days, followed by 120 mg febuxostat for 4 days, and a single 10 mg dose of rosuvastatin on day 6. Febuxostat increased the peak plasma concentration and area under the plasma concentration-time curve of rosuvastatin 2.1-fold (90% confidence interval 1.8-2.6; P = 5 × 10 ) and 1.9-fold (1.5-2.5; P = 0.001), but had no effect on rosuvastatin half-life or renal clearance. Allopurinol, on the other hand, did not affect rosuvastatin pharmacokinetics. In vitro, febuxostat inhibited the ATP-dependent uptake of rosuvastatin into BCRP-overexpressing membrane vesicles with a half-maximal inhibitory concentration of 0.35 µM, whereas allopurinol showed no inhibition with concentrations up to 200 µM. Taken together, the results suggest that febuxostat increases rosuvastatin exposure by inhibiting its BCRP-mediated efflux in the small intestine. Febuxostat may, therefore, serve as a useful index inhibitor of BCRP in drug-drug interaction studies in humans. Moreover, concomitant use of febuxostat may increase the exposure to BCRP substrate drugs and, thus, the risk of dose-dependent adverse effects.
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http://dx.doi.org/10.1111/cts.12809DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7719384PMC
November 2020

gem-Diol-Type Intermediate in the Activation of a Ketone on Sn-β Zeolite as Studied by Solid-State NMR Spectroscopy.

Angew Chem Int Ed Engl 2020 Oct 29;59(44):19532-19538. Epub 2020 Jun 29.

National Centre for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.

Lewis acid zeolites have found increasing application in the field of biomass conversion, in which the selective transformation of carbonyl-containing molecules is of particular importance due to their relevance in organic synthesis. Mechanistic insight into the activation of carbonyl groups on Lewis acid sites is challenging and critical for the understanding of the catalytic process, which requires the identification of reaction intermediates. Here we report the observation of a stable surface gem-diol-type species in the activation of acetone on Sn-β zeolite. C, Sn, and C- Sn double-resonance NMR spectroscopic studies demonstrate that only the open Sn site ((SiO) Sn-OH) on Sn-β is responsible for the formation of the surface species. C MAS NMR experiments together with density functional theory calculations suggest that the gem-diol-type species exhibits high reactivity and can serve as an active intermediate in the Meerwein-Ponndorf-Verley-Oppenauer (MPVO) reaction of acetone with cyclohexanol. The gem-diol-type species offers an energy-preferable pathway for the direct carbon-to-carbon hydrogen transfer between ketone and alcohol. The results provide new insights into the transformation of carbonyl-containing molecules catalyzed by Lewis acid zeolites.
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http://dx.doi.org/10.1002/anie.202005589DOI Listing
October 2020

Inside-out azimuthally selective NMR tool using array coil and capacitive decoupling.

J Magn Reson 2020 Jun 28;315:106735. Epub 2020 Apr 28.

PetroChina Research Institute of Petroleum Exploration and Development, Beijing, China.

Inside-out nuclear magnetic resonance (NMR) is a unique technique for investigating large in-situ objects outside of tools, to provide pore structure and pore-bearing fluids properties. However, in borehole, objects towards azimuthal orientations pose different properties, referred to as azimuthal spatial heterogeneity. This may lead to ambiguous evaluations by utilizing present inside-out NMR measurement, which hardly resolves azimuthal information and loses the location information of oil/gas. In this paper, we for the first time design and construct an innovative tool to investigate the heterogeneity of large in-situ samples. The most key component, array coil, which performs with azimuthal selection, measurement consistency and interactive isolation, configured in this novel tool to capture heterogeneity information. Whereas, strong coupling between neighboring coil elements largely decrease the coil sensitivity. Capacitive decoupling network is bridged into adjacent ports without segmenting coils to be decoupled and could be easily adjusted by electrical relays. The coil model and numerical simulation are firstly given to demonstrate the array coil configuration, B field map and mutual coupling effects on coil sensitivity. Capacitive network is then introduced to be theoretically and practically analyzed to minimize coupling effects. Simulation and experimental results demonstrate that these coil elements have excellent consistency and independence to feasibly acquire the azimuthal NMR data.
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http://dx.doi.org/10.1016/j.jmr.2020.106735DOI Listing
June 2020

Novel Modification of Collagen: Realizing Desired Water Solubility and Thermostability in a Conflict-Free Way.

ACS Omega 2020 Mar 11;5(11):5772-5780. Epub 2020 Mar 11.

College of Materials Engineering, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.

Because of poor water solubility and low thermostability, the application of collagen is limited seriously in fields such as injectable biomaterials and cosmetics. In order to overcome the two drawbacks simultaneously, a novel bifunctional modifier based on the esterification of polyacrylic acid (PAA) with -hydroxysuccinimide (NHS) was prepared. The esterification degree of PAA-NHS esters was increased upon increasing the NHS dose, which was confirmed by Fourier-transform infrared (FTIR) and nuclear magnetic resonance spectrascopy. FTIR results indicated that the triple helix of the modified collagens remained integrated, whereas the molecular weight became larger, as reflected by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis pattern. The modified collagens displayed excellent water solubility under neutral condition, owing to lower isoelectric point (3.1-4.3) than that of native collagen (7.1). Meanwhile, denaturation temperatures of the modified collagens were increased by 4.8-5.9 °C after modification. The modified collagen displayed hierarchical microstructures, as reflected by field-emission scanning electron microscopy, while atomic force microscopy further revealed a "fishing net-like" network in the nanoscale, reflecting a unique aggregation behavior of collagen macromolecules after modification. As a whole, the PAA-NHS ester as a bifunctional modifier endowed collagen with desired water solubility and thermostability in a conflict-free manner, which was beneficial to the process and application of the water-soluble collagen.
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http://dx.doi.org/10.1021/acsomega.9b03846DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7097890PMC
March 2020

Nanosized Alumina Particle and Proteasome Inhibitor Bortezomib Prevented inflammation and Osteolysis Induced by Titanium Particle via Autophagy and NF-κB Signaling.

Sci Rep 2020 03 27;10(1):5562. Epub 2020 Mar 27.

Stomatological Hospital of Chongqing Medical University, Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, 401147, Chongqing, P. R. China.

Autophagy and NF-κB signaling are involving in the process of Particle Disease, which was caused by the particles released from friction interface of artificial joint, implant materials of particle reinforced composite, scaffolds for tissue engineering, or material for drug delivery. However, the biological interaction of different material particles and the mechanism of proteasome inhibitor, Bortezomib (BTZ), against Titanium (Ti) particle-induced Particle Disease remain unclear. In this study, we evaluated effect of nanosized Alumina (Al) particles and BTZ on reducing and treating the Ti particle-induced inflammatory reaction in MG-63 cells and mouse calvarial osteolysis model. We found that Al particles and BTZ could block apoptosis and NF- κB activation in osteoblasts in vitro and in a mouse model of calvarial resorption induced by Ti particles. We found that Al particles and BTZ attenuated the expression of inflammatory cytokines (IL-1β, IL-6, TNF-α). And Al prevented the IL-1β expression induced by Ti via attenuating the NF- κB activation β-TRCP and reducing the expression of Casepase-3. Expressions of autophagy marker LC3 was activated in Ti group, and reduced by Al and/not BTZ. Furthermore, the expressions of OPG were also higher in these groups than the Ti treated group. Collectively, nanosized Al could prevent autophagy and reduce the apoptosis, inflammatory and osteolysis induced by Ti particles. Our data offered a basic data for implant design when it was inevitable to use Ti as biomaterials, considering the outstanding mechanical propertie of Ti. What's more, proteasome inhibitor BTZ could be a potential therapy for wear particle-induced inflammation and osteogenic activity via regulating the activity of NF- κB signaling pathway.
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http://dx.doi.org/10.1038/s41598-020-62254-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7101404PMC
March 2020

PAX6 contributes to the activation and proliferation of hepatic stellate cells via activating Hedgehog/GLI1 pathway.

Biochem Biophys Res Commun 2020 05 21;526(2):314-320. Epub 2020 Mar 21.

Sichuan Clinical Research Center for Geriatrics, The First Affiliated Hospital of Chengdu Medical College, Chengdu, 610500, China. Electronic address:

Aberrant activation of Hedgehog signaling is considered as the key player in hepatic stellate cell (HSC) activation involved in liver fibrosis (LF). The glioma-associated protein gene (GLI) has a predicted paired box 6 (PAX6)-binding site within its transcribed region. Therefore, this study aimed to investigate the relationship between PAX6 and GLI and their contribution to HSC activation and proliferation. PAX6 expression was upregulated in platelet-derived growth factor-BB (PDGF-BB)-induced LX-2 cells. The activation and proliferation of HSC were inhibited by interference of PAX6 with short hairpin RNA (shPAX6) via curbing Hedgehog signaling. Notably, PAX6 directly bound to the promoter sequence of GLI1 independent of the PTCH/SMO axis. Therefore, we propose that PAX6 upregulation induces HSC activation and proliferation through crosstalk with GLI1 signaling. Thus, these novel mechanistic insights involving the PAX6-mediated regulation of the activation and proliferation of HSC may provide a new therapeutic target for LF.
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http://dx.doi.org/10.1016/j.bbrc.2020.03.086DOI Listing
May 2020

Backwashing behavior and hydrodynamic performances of granular activated carbon blends.

Environ Res 2020 05 25;184:109302. Epub 2020 Feb 25.

School of Chemical and Environmental Engineering, China University of Mining & Technology (Beijing), Beijing, 10083, China.

Ozone-biological activated carbon (O-BAC) process has been proved to be an efficient and cost-effective technology in advanced treatment of drinking water. However, O-BAC raises strict requirements in adsorption, hydrodynamic and regeneration performances, which one single activated carbon could hardly all-sided meet. Blending activated carbons seems to be an appropriate and economically feasible method to deal with the issue. Thus, the uniformity and stability of activated carbon blends during water treatment, especially in backwashing process are of great importance. In this paper, cyclic experiments of downward adsorption and upward backwash on 11 typical commercial granular coal-based activated carbons and their blends were carried out in column test. Hydrodynamic performances such as bed expansion rate and bed pressure drop were measured. The uniformity and stability of activated carbon blends were investigated by determining iodine number of samples collected from different heights of activated carbon bed. Then, both traditional regression methods and back-propagation neural network model were utilized to predict superficial velocity at 30% bed expansion rate and maximum bed pressure drop of activated carbon blends. The results indicate that water backwashing process has no effect on the composition proportion of activated carbon blends, and slightly changes the particle distribution of activated carbon bed regarding pore structure and adsorption capacity. A three-layer back-propagation neural network model for superficial velocity at 30% bed expansion rate yields mean relative errors of 2.17%, which is much lower than that given by traditional regression methods such as 5.53% (weighted average), 4.08% (linear) and 4.06% (polynomial). Moreover, the back-propagation neural network model for maximum bed pressure drop yields mean relative errors of 1.37%, which is much lower than that given by traditional regression methods such as 4.31% (weighted average), 4.28% (linear) and 4.22% (polynomial). The non-linear relationships can be accurately identified by the back-propagation neural network model.
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http://dx.doi.org/10.1016/j.envres.2020.109302DOI Listing
May 2020

π-Interactions between Cyclic Carbocations and Aromatics Cause Zeolite Deactivation in Methanol-to-Hydrocarbon Conversion.

Angew Chem Int Ed Engl 2020 Apr 10;59(18):7198-7202. Epub 2020 Mar 10.

National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, P. R. China.

The understanding of catalyst deactivation represents one of the major challenges for the methanol-to-hydrocarbon (MTH) reaction over acidic zeolites. Here we report the critical role of intermolecular π-interactions in catalyst deactivation in the MTH reaction on zeolites H-SSZ-13 and H-ZSM-5. π-interaction-induced spatial proximities between cyclopentenyl cations and aromatics in the confined channels and/or cages of zeolites are revealed by two-dimensional solid-state NMR spectroscopy. The formation of naphtalene as a precursor to coke species is favored due to the reaction of aromatics with the nearby cyclopentenyl cations and correlates with both acid density and zeolite topology.
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http://dx.doi.org/10.1002/anie.202000637DOI Listing
April 2020

The acidic nature of "NMR-invisible" tri-coordinated framework aluminum species in zeolites.

Chem Sci 2019 Nov 12;10(43):10159-10169. Epub 2019 Sep 12.

National Centre for Magnetic Resonance in Wuhan , State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics , CAS Key Laboratory of Magnetic Resonance in Biological Systems , Wuhan Institute of Physics and Mathematics , Chinese Academy of Sciences , Wuhan 430071 , China . Email: ; Email:

The unambiguous characterization of different acid sites in zeolites is of great importance for understanding their catalytic performance and the rational design of highly efficient zeolite catalysts. In addition to various well-characterized extra-framework Al species, a tri-coordinated framework aluminum species can also serve as a Lewis acid site in zeolites, which is "NMR-invisible" owing to its extremely distorted local environment. Here we provide a feasible and reliable approach to elucidate the acidic nature of the tri-coordinated framework Al in dehydrated H-ZSM-5 zeolites sensitivity-enhanced two-dimensional (2D) multiple nuclear correlation NMR experiments coupled with trimethylphosphine oxide (TMPO) probe molecules. Two types of tri-coordinated framework Al sites have been unambiguously identified, which amount to 11.6% of the total Brønsted and Lewis acid sites. Furthermore, it was found that synergistic effects arising from the close spatial proximity between the tri-coordinated framework Al site and the Brønsted acid site lead to the generation of superacidity (with an acid strength stronger than 100% HSO) in the zeolite.
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http://dx.doi.org/10.1039/c9sc02634gDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6979346PMC
November 2019

Hydroiodic Acid Additive Enhanced the Performance and Stability of PbS-QDs Solar Cells via Suppressing Hydroxyl Ligand.

Nanomicro Lett 2020 Jan 24;12(1):37. Epub 2020 Jan 24.

Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan, 430074, People's Republic of China.

The recent emerging progress of quantum dot ink (QD-ink) has overcome the complexity of multiple-step colloidal QD (CQD) film preparation and pronouncedly promoted the device performance. However, the detrimental hydroxyl (OH) ligands induced from synthesis procedure have not been completely removed. Here, a halide ligand additive strategy was devised to optimize QD-ink process. It simultaneously reduced sub-bandgap states and converted them into iodide-passivated surface, which increase carrier mobility of the QDs films and achieve thicker absorber with improved performances. The corresponding power conversion efficiency of this optimized device reached 10.78%. (The control device was 9.56%.) Therefore, this stratege can support as a candidate strategy to solve the QD original limitation caused by hydroxyl ligands, which is also compatible with other CQD-based optoelectronic devices.
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http://dx.doi.org/10.1007/s40820-020-0372-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7770827PMC
January 2020
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