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1.
Chem Sci ; 13(19): 5531-5538, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35694345

RESUMO

The controllable preparation of metal nanoclusters in high yield is an essential prerequisite for their fundamental research and extensive application. Here a synthetic approach termed "dual-level kinetic control" was developed to fabricate a family of new silver nanoclusters. The introduction of secondary ligands was first exploited to retard the reduction rate and accomplish the first-level kinetic control. And the cooling of the reaction was performed to further slow the reduction down and accomplish the second-level kinetic control. A family of atomically precise silver nanoclusters (including [Ag25(SR)18]-, [Ag34(SR)18(DPPP)3Cl4]2+, [Ag36(SR)26S4]2+, [Ag37(SR)25Cl1]+, and [Ag52(SR)28Cl4]2+) were controllably prepared and structurally determined. The developed "dual-level kinetic control" hopefully acts as a powerful synthetic tool to manufacture more nanoclusters with unprecedented compositions, structures, and properties.

2.
Angew Chem Int Ed Engl ; 61(31): e202205947, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35596616

RESUMO

It remains challenging to manipulate the nature of photoluminescence as either fluorescence or phosphorescence for a correlated cluster series. In this work, two correlated nanoclusters, Au5 Ag11 (SR)8 (DPPOE)2 and Pt1 Ag16 (SR)8 (DPPOE)2 with comparable structure features, were synthesized and structurally determined. These two alloy nanoclusters displayed distinct photoluminescent nature-the Au5 Ag11 nanocluster is fluorescent, whereas the Pt1 Ag16 nanocluster is phosphorescent. The decay processes of the excited electrons in these two nanoclusters have been explicitly mapped out by both experimental and theoretical approaches, disclosing the mechanisms of their fluorescence and phosphorescence. Specifically, the metallic compositions of the nanocluster kernels mattered in determining their photoluminescent nature. The results herein provide an intriguing nanomodel that enables us to grasp the origin of photoluminescence at the atomic level, which further paves the way for fabricating novel nanoclusters or cluster-based nanomaterials with customized photophysical properties.

3.
Chem Commun (Camb) ; 58(33): 5092-5095, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35381055

RESUMO

The intermolecular metallophilic interaction has been exploited to orderly aggregate nanocluster compounds into multidimensional assemblies, while the intramolecular metallophilic interaction was rarely reported. Herein, based on an Au13Cu2 nanocluster template, the presence of the intracluster Au-Cu metallophilic interaction was beneficial to achieving enhanced near-infrared emission intensity and thermal stability.

4.
Chem Sci ; 13(5): 1382-1389, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35222922

RESUMO

Silver nanoclusters have received unprecedented attention in cluster science owing to their promising functionalities and intriguing physical/chemical properties. However, essential instability significantly impedes their extensive applications. We herein propose a strategy termed "surface environment complication" to endow Ag29 nanoclusters with high robustness. The Ag29(S-Adm)18(PPh3)4 nanocluster with monodentate PPh3 ligands was extremely unstable and uncrystallizable. By substituting PPh3 with bidentate PPh2py with dual coordination sites (i.e., P and N), the Ag29 cluster framework was twisted because of the generation of N-Ag interactions, and three NO3 ligands were further anchored onto the nanocluster surface, yielding a new Ag29(S-Adm)15(NO3)3(PPh2py)4 nanocluster with high stability. The metal-control or ligand-control effects on stabilizing the Ag29 nanocluster were further evaluated. Besides, Ag29(S-Adm)15(NO3)3(PPh2py)4 followed a unique packing mode in the supracrystal lattice with several intercluster channels, which has yet been observed in other M29 cluster crystals. Overall, this work presents a new approach (i.e., surface environment complication) for tailoring the surface environment and improving the stability of metal nanoclusters.

5.
J Am Chem Soc ; 144(11): 4845-4852, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35167256

RESUMO

Accomplishing optical activity in achiral materials has long been a challenge. Achiral nanomaterials that crystallize in achiral point groups are generally optically inactive. Herein we report the surprising observation of optical activity in several achiral point groups for supercrystals assembled from anisotropic metal nanoclusters with atomic precision. By analyzing multiple achiral nanoclusters with different molecular structures and symmetry space groups, we have identified that the molecular anisotropy of nanocluster entities and their asymmetric arrangement in point groups of supercrystals are the two key factors for the realization of optical activity in such supercrystals. We have further exploited the polarization effect of the nanocluster supercrystals as a polarization switch that can alter the polarized state of the linearly polarized light. Our findings have broadened the fundamental principles for producing nanomaterial-based optical activity and devices with polarization effects.


Assuntos
Nanoestruturas , Anisotropia , Cristalografia , Estrutura Molecular , Rotação Ocular
6.
J Am Chem Soc ; 144(9): 3787-3792, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35225599

RESUMO

The inorganic-organic interface between metal catalysts and their substrates greatly influences reaction processes, but few studies of this interface have been conducted for a detailed understanding of its structure. Herein, we describe the synthesis and structural determination of an arylthiolated Au25(F-Ph)18- nanocluster and characterize in detail the key roles of its ligands in photocatalyzed oxidative functionalization reactions. The most significant findings are that (i) interactions are established between ligands to avoid distortion of the geometric structure, limit the Jahn-Teller effect, and protect the nanocluster from oxidization and (ii) the low energy gap (HOMO-LUMO) of the synthetic clusters enables three types of photocatalytic oxidative functionalization reactions by near-infrared light (850 nm).

7.
Int J Biol Macromol ; 202: 529-538, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35066019

RESUMO

The pro-inflammatory cytokine interleukin-17A (IL-17A) is a key driver of multiple inflammatory and immune disorders. Therapeutic antibodies targeting IL-17A have been proven effective in treating patients with these diseases; however, large variations in clinical outcomes have been observed with different antibodies. In this study, we developed HB0017, a novel monoclonal antibody that targets human IL-17A. HB0017 specifically and strongly bound to human, cynomolgus monkey, and mouse IL-17A at the physiological interface with the IL-17A receptor. In human and monkey cells, HB0017 potently antagonized the functions of IL-17A through competitive binding. HB0017 functioned equivalently to that of clinically approved antibodies in terms of therapeutic efficacy for inflammatory disorders and psoriasis in a mouse model. The results indicate that HB0017 may be an alternative biological therapy for treating patients with inflammation and autoimmune diseases.


Assuntos
Doenças Autoimunes , Psoríase , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Humanos , Interleucina-17 , Macaca fascicularis/metabolismo , Camundongos , Psoríase/tratamento farmacológico
8.
Natl Sci Rev ; 8(3): nwaa077, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34691583

RESUMO

The supramolecular chemistry of nanoclusters is a flourishing area of nano-research; however, the controllable assembly of cluster nano-building blocks in different arrays remains challenging. In this work, we report the hierarchical structural complexity of atomically precise nanoclusters in micrometric linear chains (1D array), grid networks (2D array) and superstructures (3D array). In the crystal lattice, the Ag29(SSR)12(PPh3)4 nanoclusters can be viewed as unassembled cluster dots (Ag29-0D). In the presence of Cs+ cations, the Ag29(SSR)12 nano-building blocks are selectively assembled into distinct arrays with different oxygen-carrying solvent molecules-Cs@Ag29(SSR)12(DMF) x as 1D linear chains (Ag29-1D), Cs@Ag29(SSR)12(NMP) x as 2D grid networks (Ag29-2D), and Cs@Ag29(SSR)12(TMS) x as 3D superstructures (Ag29-3D). Such self-assemblies of these Ag29(SSR)12 units have not only been observed in their crystalline state, but also in their amorphous state. Due to the diverse surface structures and crystalline packing modes, these Ag29-based assemblies manifest distinguishable optical absorptions and emissions in both solutions and crystallized films. Furthermore, the surface areas of the nanocluster crystals are evaluated, the maximum value of which occurs when the cluster nano-building blocks are assembled into 2D arrays (i.e. Ag29-2D). Overall, this work presents an exciting example of the hierarchical assembly of atomically precise nanoclusters by simply controlling the adsorbed molecules on the cluster surface.

9.
Nat Commun ; 12(1): 6186, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34702816

RESUMO

Although the hollow icosahedral M12 kernel has been extensively observed in metal nanoclusters, its origin remains a mystery. Here we report a reasonable avenue for the generation of the hollow icosahedron: the kernel collapse from several small nano-building blocks to an integrated hollow icosahedron. On the basis of the Au alloying processes from Ag28Cu12(SR)24 to the template-maintained AuxAg28-xCu12(SR)24 and then to the template-transformed Au12CuyAg32-y(SR)30, the kernel evolution/collapse from "tetrahedral Ag4 + 4∗Ag3" to "tetrahedral Au4 + 4∗M3 (M = Au/Ag)" and then to "hollow icosahedral Au12" is mapped out. Significantly, the "kernel collapse" from small-sized nano-building blocks to large-sized nanostructures not only unveils the formation of hollow icosahedral M12 in this work, but also might be a very common approach in constructing metallic kernels of nanoclusters and nanoparticles (not limited to the M12 structure).

10.
Nanoscale ; 13(40): 17162-17167, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34636384

RESUMO

Although several approaches have been exploited to trigger the structural transformation of metal nanoclusters, most cases are assigned to the unidirectional conversion, while the reversible conversion of nanoclusters remains challenging. In this work, the reversible conversion between two Au-Ag alloy nanoclusters, Au14Ag8(Dppm)6(CN)4Cl4 and Au14Ag4(Dppm)6Cl4, has been accomplished, which was tracked by UV-vis and ESI-MS spectroscopy. The condition of the nanocluster reversible conversion has been meticulously mapped out. Our results provide some new insights into the cluster transformation, which will benefit the future preparation of metalloid clusters with customized structures and properties.

11.
Nanomaterials (Basel) ; 11(10)2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34685097

RESUMO

Surface modification has served as an efficient approach to dictate nanocluster structures and properties. In this work, based on an Ag22 nanocluster template, the effects of surface modification on intracluster constructions and intercluster packing modes, as well as the properties of nanoclusters or cluster-based crystallographic assemblies have been investigated. On the molecular level, the Ag22 nanocluster with larger surface steric hindrance was inclined to absorb more small-steric chlorine but less bulky thiol ligands on its surface. On the supramolecular level, the regulation of intramolecular and intermolecular interactions in nanocluster crystallographic assemblies rendered them CIEE (crystallization-induced emission enhancement)-active or -inactive nanomaterials. This study has some innovation in the molecular and intramolecular tailoring of metal nanoclusters, which is significant for the preparation of new cluster-based nanomaterials with customized structures and enhanced performances.

12.
Inorg Chem ; 60(19): 14803-14809, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34516083

RESUMO

Cl atoms can serve as the innermost core, the peripheral ligand, or the counterions of metal nanoclusters. Herein, we report the structural determination a Cl-enriched [Ag52(SAdm)31Cl13]2+. The ratio of Cl to AdmSH is quite high compared to those of other nanoclusters. Structurally, nine Cl atoms, existing at the interlayer of the inner kernel and the surface motif, serve as the bridging ligands to sustain the robustness of the whole structure. Interestingly, four Cl atoms on the motif structure can be substituted by Br. This work allows us to clear the regulation of Cl ligands in the structural construction of metal nanoclusters.

13.
Chem Sci ; 12(33): 11080-11088, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34522305

RESUMO

The polarization effect has been a powerful tool in controlling the morphology of metal nanoparticles. However, a precise investigation of the polarization effect has been a challenging pursuit for a long time, and little has been achieved for analysis at the atomic level. Here the atomic-level analysis of the polarization effect in controlling the morphologies of metal nanoclusters is reported. By simply regulating the counterions, the controllable transformation from Pt1Ag28(S-PhMe2) x (S-Adm)18-x (PPh3)4 (x = 0-6, Pt1Ag28-2) to Pt1Ag24(S-PhMe2)18 (Pt1Ag24) with a spherical configuration or to Pt1Ag28(S-Adm)18(PPh3)4 (Pt1Ag28-1) with a tetrahedral configuration has been accomplished. In addition, the spherical or tetrahedral configuration of the clusters could be reversibly transformed by re-regulating the proportion of counterions with opposite charges. More significantly, the configuration transformation rate has been meticulously manipulated by regulating the polarization effect of the ions on the parent nanoclusters. The observations in this paper provide an intriguing nanomodel that enables the polarization effect to be understood at the atomic level.

14.
Inorg Chem ; 60(15): 11640-11647, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34286977

RESUMO

The structural determination of alloy hydride nanoclusters with high nuclearity remains challenging. We herein report the synthetic procedure and the structural elucidation of an Au-Ag alloy nanocluster with 12 hydride ligands-[Au16Ag43H12(SPhCl2)34]5-. The structure of [Au16Ag43H12(SPhCl2)34]5- comprises an Au16Ag3 kernel that is stabilized by 12 hydride ligands, 8 thiol bridges, and 6 Agm(SR)n motif units. The 12 hydride ligands in Au16Ag43 have been confirmed by both 2H NMR and ESI-MS measurements, and their positions have been theoretically evaluated, located at the interlayer between the Au16Ag3 kernel and the Ag-SR shell. The metastable [Au16Ag43H12(SPhCl2)34]5- can convert to [Au12Ag32(SPhCl2)30]4- spontaneously. Structurally, the Au16Ag3 kernel of [Au16Ag43H12(SPhCl2)34]5- could be regarded as the overlapping of two hollow Au8Ag3 cages via sharing an Ag3 line, which is in contrast to the solely icosahedral Au12 kernel of [Au12Ag32(SPhCl2)30]4-. Besides, the overall construction of Au16Ag43 or Au12Ag32 follows a complementing or overlapping assembly mode, respectively. Overall, the structural anatomy of Au16Ag43H12(SPhCl2)34 sheds some new insight into the structural evolution of metal nanoclusters.

15.
J Chem Phys ; 154(18): 184302, 2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34241021

RESUMO

The structure/composition of nanoclusters has a decisive influence on their physicochemical properties. In this work, we obtained two different Au-Ag nanoclusters, [Au9Ag12(SAdm)4(dppm)6Cl6]3+ and Au11Ag6(dppm)4(SAdm)4(CN)4, via controlling the Au/Ag molar ratios by a one-pot synthetic approach. The structure of nanoclusters was confirmed and testified by single-crystal x-ray diffraction, electrospray ionization time-of-flight mass spectrometry, XPS, powder x-ray diffraction, and electron paramagnetic resonance. The Au11Ag6 nanocluster possessed a M13 core caped by four Au atoms and four dppm and four AdmS ligands. Interestingly, four CN are observed to locate at the equator of the M13 core. Both nanoclusters contain a similar icosahedral M13 core, whereas their surface structures are totally different. However, the Au11Ag6 nanocluster exhibits good stability and strong red photoluminescence in solution.

16.
Chem Sci ; 12(10): 3660-3667, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-34163640

RESUMO

By introducing 1,1'-bis-(diphenylphosphino)ferrocene (dppf) as an activating ligand, two novel nanoclusters, M1Ag21 (M = Au/Ag), have been controllably synthesized and structurally characterized. The atomically precise structures of the M1Ag21 nanoclusters were determined by SCXC and further confirmed by ESI-TOF-MS, TGA, XPS, DPV, and FT-IR measurements. The M1Ag21 nanoclusters supported on activated carbon (C) are exploited as efficient oxygen reduction reaction (ORR) catalysts in alkaline solutions. Density functional theory (DFT) calculations verify that the catalytic activities of the two cluster-based systems originate from the significant ensemble synergy effect between the M13 kernel and dppf ligand in M1Ag21. This work sheds lights on the preparation of cluster-based electrocatalysts and other catalysts that are activated and modified by peripheral ligands.

17.
Hortic Res ; 8(1): 122, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34059664

RESUMO

Simple sequence repeats (SSRs) are one of the most important genetic markers and widely exist in most species. Here, we identified 249,822 SSRs from 3,951,919 genes in 112 plants. Then, we conducted a comprehensive analysis of these SSRs and constructed a plant SSR database (PSSRD). Interestingly, more SSRs were found in lower plants than in higher plants, showing that lower plants needed to adapt to early extreme environments. Four specific enriched functional terms in the lower plant Chlamydomonas reinhardtii were detected when it was compared with seven other higher plants. In addition, Guanylate_cyc existed in more genes of lower plants than of higher plants. In our PSSRD, we constructed an interactive plotting function in the chart interface, and users can easily view the detailed information of SSRs. All SSR information, including sequences, primers, and annotations, can be downloaded from our database. Moreover, we developed Web SSR Finder and Batch SSR Finder tools, which can be easily used for identifying SSRs. Our database was developed using PHP, HTML, JavaScript, and MySQL, which are freely available at http://www.pssrd.info/ . We conducted an analysis of the Myb gene families and flowering genes as two applications of the PSSRD. Further analysis indicated that whole-genome duplication and whole-genome triplication played a major role in the expansion of the Myb gene families. These SSR markers in our database will greatly facilitate comparative genomics and functional genomics studies in the future.

18.
Oncogene ; 40(19): 3422-3433, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33883692

RESUMO

Peritoneal metastasis is a common form of metastasis among advanced gastric cancer patients. In this study, we reported the identification of LIM domain kinase 1 (LIMK1) as a promoter of gastric cancer peritoneal metastasis, and its potential to be a therapeutic target of dabrafenib (DAB). Using transcriptomic sequencing of paired gastric cancer peritoneal metastasis, primary tumors, and normal gastric tissues, we first unveiled that LIMK1 is selectively up-regulated in metastatic tumors. Increased LIMK1 in gastric cancer peritoneal metastasis was validated by immunohistochemistry analysis of an independent patient cohort. In vitro functional studies demonstrated that LIMK1 knockout or knockdown significantly inhibited cell migration and invasion of gastric cancer cells. LIMK1 knockout also abrogated peritoneal and liver metastases of gastric cancer cells in nude mice in vivo. Dabrafenib, a small molecule targeting LIMK1, was found to decrease cell migration and invasion of gastric cancer cells in vitro and abolish peritoneal and liver metastasis formation in vivo. Mechanistically, either LIMK1 knockout or Dabrafenib inhibited LIMK1 expression and phosphorylation of its downstream target cofilin. Taken together, our results demonstrated that LIMK1 functions as a metastasis promoter in gastric cancer by inhibiting LIMK1-p-cofilin and that Dabrafenib has the potential to serve as a novel treatment for gastric cancer peritoneal metastasis.


Assuntos
Quinases Lim/metabolismo , Neoplasias Peritoneais/secundário , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Imidazóis/farmacologia , Quinases Lim/antagonistas & inibidores , Quinases Lim/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Terapia de Alvo Molecular , Metástase Neoplásica , Oximas/farmacologia , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Análise de Sequência de RNA , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Taxa de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Inorg Chem ; 60(8): 5931-5936, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33826306

RESUMO

The determination of active sites in metal nanoclusters is of great significance for the in-depth understanding of the structural evolution and the mechanism of physicochemical properties. In this work, the surface active Ag2(SR)3 units of the Ag48Cl14(S-Adm)30 nanocluster are determined, and the active-site tailoring of this nanocluster gives rise to two derivative nanoclusters, i.e., the structure-maintained Ag48Cl14(S-Adm)26(S-c-C6H11)4 and the structure-growth Ag50Cl16(S-Adm)28(DPPP)2. Both Ag48 and Ag50 nanoclusters exhibit almost the same cluster framework, but the Ag2(S-Adm)3 active units are regulated to Ag3(S-Adm)2(DPPP)1Cl1 with the transformation from Ag48 to Ag50. The surface active sites on Ag48 are rationalized by analyzing its crystal structure and the ligand-exchange-induced cluster transformation. This study provides some inspiration toward the active-site tailoring of nanocluster surface structures, which is significant for the preparation of new cluster-based nanomaterials with customized structures and enhanced performance.

20.
Sci Rep ; 11(1): 7776, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33833338

RESUMO

This study investigated associations between cardiometabolic diseases, frailty, and healthcare utilization and expenditure among Chinese older adults. The participants were 5204 community-dwelling adults aged at least 60 years from the China Health and Retirement Longitudinal Study. Five cardiometabolic diseases were assessed including hypertension, dyslipidemia, diabetes, cardiac diseases and stroke. Frailty status was based on five criteria: slowness, weakness, exhaustion, inactivity, and shrinking. Participants were deemed frailty if they met at least three criteria. As the number of cardiometabolic diseases increased, so did the prevalence of frailty, and the proportion of healthcare utilization, including outpatient visit and inpatient visit. Moreover, the total healthcare expenditure and the odds of catastrophic health expenditure were increased with the number of cardiometabolic disorders. After adjusting for covariates, cardiometabolic diseases were positively associated with higher odds of frailty, incurring outpatient and inpatient visit. And individuals with 2 or more cardiometabolic diseases had a higher odds of catastrophic health expenditure than persons with non-cardiometabolic disease. Participants who were frailty were more likely to report higher odds of healthcare utilization. These findings suggest that both cardiometabolic diseases and frailty assessment may improve identification of older adults likely to require costly, extensive healthcare.


Assuntos
Fragilidade/epidemiologia , Avaliação Geriátrica , Gastos em Saúde/estatística & dados numéricos , Cardiopatias/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Idoso , China/epidemiologia , Feminino , Idoso Fragilizado , Humanos , Hipertensão/epidemiologia , Vida Independente , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários
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