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1.
Small ; 16(10): e1906846, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32026590

RESUMO

Metal-organic frameworks (MOFs) are an interesting and useful class of coordination polymers, constructed from metal ion/cluster nodes and functional organic ligands through coordination bonds, and have attracted extensive research interest during the past decades. Due to the unique features of diverse compositions, facile synthesis, easy surface functionalization, high surface areas, adjustable porosity, and tunable biocompatibility, MOFs have been widely used in hydrogen/methane storage, catalysis, biological imaging and sensing, drug delivery, desalination, gas separation, magnetic and electronic devices, nonlinear optics, water vapor capture, etc. Notably, with the rapid development of synthetic methods and surface functionalization strategies, smart MOF-based nanocomposites with advanced bio-related properties have been designed and fabricated to meet the growing demands of MOF materials for biomedical applications. This work outlines the synthesis and functionalization and the recent advances of MOFs in biomedical fields, including cargo (drugs, nucleic acids, proteins, and dyes) delivery for cancer therapy, bioimaging, antimicrobial, biosensing, and biocatalysis. The prospects and challenges in the field of MOF-based biomedical materials are also discussed.

2.
J Mater Chem B ; 8(11): 2238-2249, 2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32096816

RESUMO

Incorporation of dual functions, i.e., sensing and adsorption, into one single organic-inorganic hybrid material for the detection and removal of toxic permanganate (MnO4-) ions is of great importance, representing a challenging and new task in the design and application of new functional materials. However, most of the reported materials display only one function as either sensing probes or adsorbents. In this work, a fluorescent cuboid mesoporous silica-based hybrid material (SiO2@SFNO) is first prepared by the covalent coupling of a new safranin O-based fluorophore (2,8-dimethyl-5-phenyl-3,7-bis(3-(3-(triethoxysilyl)propyl)ureido)phenazin-5-ium chloride) (SFNO) and newly-made cuboid mesoporous silica, which showed selective dual-functional activities towards MnO4- and green emission at 575 nm with a long-range excitation wavelength that is suitable for bio-imaging application. The design of this SiO2@SFNO material is based on the position of -NHCONH- groups, which are mainly responsible for the strong and selective coordination with MnO4-. SiO2@SFNO is responsive to MnO4- at parts per billion (67 ppb) level; it also displays high adsorption ability (292 mg g-1) to MnO4- in aqueous solutions. The fluorescence responses of MnO4-in vivo (limnodrilus claparedianus and zebrafish) demonstrate the possibility of further application in biology. Interestingly, this SiO2@SFNO material is also capable of monitoring trace amounts of Hg2+ and Cu2+ in living organisms, holding great potential in bio-related applications.

3.
Chem Commun (Camb) ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32003396

RESUMO

Construction of large multi-component coordination cages becomes much more challenging as the number of building blocks increases. A giant hexameric calix[4]resorcinarene-based coordination cage (cage-1) was successfully designed through the precise tuning of ancillary rigid tetracarboxylic acid. Significantly, cage-1 exhibited reversible uptake of volatile iodine, suggesting that it could serve as a porous material for efficient capture and separation of radioactive iodine.

4.
J Am Chem Soc ; 142(4): 2042-2050, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31935077

RESUMO

A class of γ-cyclodextrin-containing hybrid frameworks (CD-HFs) has been synthesized, employing γ-cyclodextrin (γ-CD) as the primary building blocks, along with 4-methoxysalicylate (4-MS-) anions as the secondary building blocks. CD-HFs are constructed through the synergistic exploitation of coordinative, electrostatic, and dispersive forces. The syntheses have been carried out using an organic counteranion co-assembly strategy, which allows for the introduction of 4-MS-, in place of inorganic OH-, into the cationic γ-CD-containing metal-organic frameworks (CD-MOFs). Although the packing arrangement of the γ-CD tori in the solid-state superstructure of CD-HFs is identical to that of the previously reported CD-MOFs, CD-HFs crystallize with lower symmetry and in the cuboid space group P43212-when compared to CD-MOF-1, which has the cubic unit cell of I432 space group-on account of the chiral packing of the 4-MS- anions in the CD-HF superstructures. Importantly, CD-HFs have ultramicroporous apertures associated with the pore channels, a significant deviation from CD-MOF-1, as a consequence of the contribution from the 4-MS- anions, which serve as supramolecular baffles. In gas adsorption-desorption experiments, CD-HF-1 exhibits a Brunauer-Emmett-Teller (BET) surface area of 306 m2 g-1 for CO2 at 195 K, yet does not uptake N2 at 77 K, confirming the difference in porosity between CD-HF-1 and CD-MOF-1. Furthermore, the 4-MS- anions in CD-HF-1 can be exchanged with OH- anions, leading to an irreversible single-crystal to single-crystal transformation, with rearrangement of coordinated metal ions. Reversible transformations were also observed in CD-MOF-1 when OH- ions were exchanged for 4-MS- anions, with the space group changing from I432 to R32. This organic counteranion co-assembly strategy opens up new routes for the construction of hybrid frameworks, which are inaccessible by existing de novo MOF assembly methodologies.

5.
Chem Commun (Camb) ; 56(9): 1381-1384, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31910250

RESUMO

Grignard reagents (RMgX) are widely used in organic synthesis. However, these highly reactive compounds are supplied in inflammable solvents, which causes extra complexity in their transportation. Herein we report that Grignard reagents with linear alkyl chains can be entrapped and stabilized by the macrocyclic host pillar[5]arene while preserving their reactivity.

6.
Nanoscale ; 12(4): 2180-2200, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31916548

RESUMO

Supramolecular gels constructed from low-molecular-weight gelators via noncovalent interactions have received increasing attention. The rapid development of stimuli-responsive supramolecular gels with attractive properties is highly desirable to meet the ever-growing demand of materials science and chemistry. The inherent reversible and dynamic nature of noncovalent interactions in supramolecular gels endows the materials with sensing, processing, and actuating functions in response to specific environmental changes and offers them great potential in flexible biomaterials and intelligent devices. In particular, pillar[n]arenes with symmetrical pillar-shaped architectures have been recognized as an emerging class of synthetic macrocycles after crown ethers, cyclodextrins, calixarenes, and cucurbiturils, and proven to be excellent candidates for the fabrication of functional supramolecular gels due to their many advantages including facile synthesis, diverse functionalization, and appealing host-guest properties. This review provides a comprehensive overview of recent progress in supramolecular gels involving pillar[n]arenes and their derivatives as synthetic macrocyclic arenes, from the viewpoints of the synthetic approach, controllable assembly, stimuli-responsiveness, and functions. Perspectives of this burgeoning field of research are also given at the end.

7.
Theranostics ; 10(2): 615-629, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31903141

RESUMO

Multifunctional supramolecular nanoplatforms that integrate the advantages of different therapeutic techniques can trigger multimodal synergistic treatment of tumors, thus representing an emerging powerful tool for cancer therapeutics. Methods: In this work, we design and fabricate a multifunctional supramolecular drug delivery platform, namely Fa-mPEG@CP5-CuS@HMSN-Py nanoparticles (FaPCH NPs), consisting of a pyridinium (Py)-modified hollow mesoporous silica nanoparticles-based drug reservoir (HMSN-Py) with high loading capacity, a layer of NIR-operable carboxylatopillar[5]arene (CP5)-functionalized CuS nanoparticles (CP5-CuS) on the surface of HMSN-Py connected through supramolecular host-guest interactions between CP5 rings and Py stalks, and another layer of folic acid (Fa)-conjugated polyethylene glycol (Fa-PEG) antennas by electrostatic interactions capable of active targeting at tumor lesions, in a controlled, highly integrated fashion for synergistic chemo-photothermal therapy. Results: Fa-mPEG antennas endowed the enhanced active targeting effect toward cancer cells, and CP5-CuS served as not only a quadruple-stimuli responsive nanogate for controllable drug release but also a special agent for NIR-guided photothermal therapy. Meanwhile, anticancer drug doxorubicin (DOX) could be released from the HMSN-Py reservoirs under tumor microenvironments for chemotherapy, thus realizing multimodal synergistic therapeutics. Such a supramolecular drug delivery platform showed effective synergistic chemo-photothermal therapy both in vitro and in vivo. Conclusion: This novel supramolecular nanoplatform possesses great potential in controlled drug delivery and tumor cellular internalization for synergistic chemo-photothermal therapy, providing a promising approach for multimodal synergistic cancer treatment.

8.
Angew Chem Int Ed Engl ; 59(6): 2251-2255, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31765068

RESUMO

Haloalkanes are important chemicals in synthetic chemistry and petrochemical industry, but the separation of their isomers is a big hurdle. Herein, we report a facile energy-efficient adsorptive separation strategy using a new class of nonporous adaptive crystals based on leaning pillar[6]arene. Desolvated perethylated leaning pillar[6]arene crystals (EtLP6) with interesting nonporous character show a preference for 1-bromoalkane isomers over 2-bromoalkane isomers. EtLP6 is capable of separating 1-bromopropane, 1-bromobutane, and 1-bromopentane from the corresponding 1:1 (v/v) mixtures of 1/2-positional isomers with purities from 89.6 % to 96.3 % in only one adsorption cycle. The selectivity is endowed by the different host-guest binding modes and different stabilities of EtLP6 crystalloids loaded with 1- and 2-positional isomers. Significantly, the guest-adsorbed assemblies are highly stable at room temperature and EtLP6 can be reused many times without any decrease in performance.

9.
Chemistry ; 26(1): 198-205, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31643112

RESUMO

A 2D supramolecular organic framework (SOF) based on synthetic macrocycles has been constructed in water by a self-assembly strategy. Two new organic monomers of this SOF, possessing viologen and azobenzene functional groups, form a stimuli-responsive host-guest system upon cooperatively binding with cucurbit[8]uril rings. The reversible formation and dissociation of 2D SOF can be realized by the isomerization of azobenzene under ultraviolet and visible light. The light-responsive property of the SOF is highly reversible and stable for up to four cycles. Moreover, azoreductase produced by Escherichia coli can reduce the N=N double bond of azobenzene entities, resulting in fluorescence recovery of the system. As an excellent and effective fluorescent probe, the SOF can detect azoreductase activity for real-time monitoring of the growth process of Escherichia coli. The dual-stimuli responsive 2D SOF is envisioned to drive the development of responsive devices with complex functions.


Assuntos
Substâncias Macromoleculares/química , NADH NADPH Oxirredutases/metabolismo , Compostos Azo/química , Hidrocarbonetos Aromáticos com Pontes/química , Escherichia coli/metabolismo , Imidazóis/química , Isomerismo , Luz , Substâncias Macromoleculares/metabolismo , NADH NADPH Oxirredutases/química , NADH NADPH Oxirredutases/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Espectrometria de Fluorescência
10.
Small ; 15(47): e1903880, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31588682

RESUMO

Endophthalmitis, derived from the infections of pathogens, is a common complication during the use of ophthalmology-related biomaterials and after ophthalmic surgery. Herein, aiming at efficient photodynamic therapy (PDT) of bacterial infections and biofilm eradication of endophthalmitis, a pH-responsive zeolitic imidazolate framework-8-polyacrylic acid (ZIF-8-PAA) material is constructed for bacterial infection-targeted delivery of ammonium methylbenzene blue (MB), a broad-spectrum photosensitizer antibacterial agent. Polyacrylic acid (PAA) is incorporated into the system to achieve higher pH responsiveness and better drug loading capacity. MB-loaded ZIF-8-PAA nanoparticles are modified with AgNO3 /dopamine for in situ reduction of AgNO3 to silver nanoparticles (AgNPs), followed by a secondary modification with vancomycin/NH2 -polyethylene glycol (Van/NH2 -PEG), leading to the formation of a composite nanomaterial, ZIF-8-PAA-MB@AgNPs@Van-PEG. Dynamic light scattering, transmission electron microscopy, and UV-vis spectral analysis are used to explore the nanoparticles synthesis, drug loading and release, and related material properties. In terms of biological performance, in vitro antibacterial studies against three kinds of bacteria, i.e., Escherichia coli, Staphylococcus aureus, and methicillin-resistant S. aureus, suggest an obvious superiority of PDT/AgNPs to any single strategy. Both in vitro retinal pigment epithelium cellular biocompatibility experiments and in vivo mice endophthalmitis models verify the biocompatibility and antibacterial function of the composite nanomaterials.

11.
Small ; 15(44): e1904569, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31573771

RESUMO

Hybrid fluorescent materials constructed from organic chelating fluorescent probes and inorganic solid supports by covalent interactions are a special type of hybrid sensing platform that has gained much interest in the context of metal ion sensing applications owing to their excellent advantages, recyclability, and solubility/dispersibility in particular, as compared with single organic fluorescent molecules. In recent decades, SiO2 materials and core-shell Fe3 O4 @SiO2 nanoparticles have become important inorganic solid materials and have been used as inorganic solid supports to hybridize with organic fluorescent receptors, resulting in multifunctional fluorescent hybrid systems for potential applications in sensing and related research fields. Therefore, recent progress in various fluorescent-group-functionalized SiO2 materials is reviewed, with a focus on mesoporous silica nanoparticles and core-shell Fe3 O4 @SiO2 nanoparticles, as interesting fluorescent organic-inorganic hybrid materials for sensing applications toward essential and toxic metal ions. Selective examples of other types of silica/silicon materials, such as periodic mesoporous organosilicas, solid SiO2 nanoparticles, fibrous silica spheres, silica nanowires, silica nanotubes, and silica hollow microspheres, are also mentioned. Finally, relevant perspectives of metal-ion-sensing-oriented silica-fluorescent probe hybrid materials are provided.

13.
Research (Wash D C) ; 2019: 1454562, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31549044

RESUMO

We construct a fluorescent supramolecular system (TPE-Q4 ⊂ DSP5) of excellent tolerance to a wide range of pH by the facile self-assembly of a new pillar[5]arene bearing disulfonated arms (DSP5) with an AIE-active tetraphenylethene-based tetratopic guest bearing four quaternary ammonium binding sites (TPE-Q4), which exhibits strong blue emission even in dilute aqueous solutions along with much higher quantum yield and longer fluorescence lifetime than TPE-Q4 itself. This appreciable property can be attributed to the supramolecular assembly-induced emission (SAIE) mechanism endowed by the host-guest inclusion complexation based on synthetic macrocycles. Remarkably, the enhanced fluorescence of the supramolecular assembly is quenched efficiently and exclusively by ferric ions in water with a high Stern-Volmer formula constant of 1.3 × 105 mol-1, demonstrating the excellent cation selectivity and visualized responsiveness in ion sensing and detection.

14.
iScience ; 19: 662-675, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31472341

RESUMO

Graphdiyne (GDY) as an emerging 2D carbon-network nanomaterial possesses many fascinating properties that lead to numerous exciting applications, but the use of GDY and its derivatives in the antibacterial field has not yet been discovered. In this study, we first report on the use and evaluation of GDY and graphdiyne oxide (GDYO) as antibacterial agents and propose the antibacterial mechanisms of GDY-based nanomaterials. GDYO has been synthesized via the surface oxidation of GDY, and the antibacterial activity of GDYO has been compared with that of GDY through a series of antibacterial tests. Surprisingly, surface oxidation endowed inert GDY with superior antibacterial capability against two representative bacterial models: Escherichia coli and Staphylococcus aureus. Antibacterial mechanism experiments disclose that the antibacterial function of GDYO is a result of reactive oxygen species-dependent oxidation stress when a dispersed GDYO suspension has a direct contact with bacteria especially under visible light irradiation.

15.
Adv Mater ; 31(37): e1903962, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31379097

RESUMO

Linear copolymer hosts bearing a number of pillar[5]arene dangling side chains are synthesized for the facile construction of highly emissive supramolecular polymer networks (SPNs) upon noncovalently cross-linking with a series of tetraphenyethylene (TPE)-based tetratopic guests terminated with different functional groups through supramolecular host-guest interactions. An extremely high fluorescence quantum yield (98.22%) of the SPNs materials is obtained in tetrahydrofuran (THF) by fine-tuning the parameters, and meanwhile supramolecular light-harvesting systems based on spherical supramolecular nanoparticles are constructed by interweaving 9,10-distyrylanthracene (DSA) and TPE-based guest molecules of aggregation-induced emission (AIE) with the copolymer hosts in the mixed solvent of THF/H2 O. The present study not only illustrates the restriction of the intramolecular rotations (RIR)-ruled emission enhancement mechanism regulated particularly by macrocyclic arene-containing copolymer hosts, but also suggests a new self-assembly approach to construct high-performance light-harvesting materials.

16.
Beilstein J Org Chem ; 15: 1262-1267, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293673

RESUMO

Fluorescent N-doped carbon dots (CN-dots) covalently functionalized with carboxylatopillar[5]arene (CP[5]), namely CCDs, have been prepared the first time. Compared with CN-dots without pillarene units, the newly constructed fluorescent CCDs could recognize Fe3+ with high selectivity. Therefore, such CCDs can potentially serve as a promising chemical sensor for Fe3+ ions.

17.
Chemistry ; 25(51): 11975-11982, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31334896

RESUMO

Organic luminescent materials with high quantum yields and/or white-light-emitting properties in particular play a crucial role in labeling and optoelectronic devices. In this work we have synthesized a new 2,3,6,7-tetramethoxy-9,10-di-p-tolylanthracene-bridged pillar[5]arene dimer with persistent mazarine blue fluorescent emission and much higher quantum yields in both solution and the solid state in comparison with its corresponding emissive linker without pillarene units, which exhibits typical aggregation-caused quenching. According to the fluorescence data and single-crystal analyses, their contrasting fluorescent performances can be rationally ascribed to their different stacking structures and intermolecular interactions. Three fluorescent guests containing different chromophores and/or terminal binding sites have also been synthesized to interact with the pillar[5]arene dimer to construct supramolecular ensembles with highly controllable luminescence, taking advantage of the stimuli-responsive properties of the supramolecular host-guest interactions. Intriguingly, multicolor fluorescence, including white-light emission (0.31, 0.35), which is in high demand, has been achieved by tuning the molar ratio of the host and guest and/or by changing the solvent system. This strategy holds great potential for the design and development of fluorescent materials with high quantum yields, controllable emission wavelength, and good stimuli-responsiveness.

18.
J Am Chem Soc ; 141(31): 12280-12287, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31314522

RESUMO

In this work, a new version of macrocyclic arenes, namely geminiarene, has been designed and synthesized for guest complexation and chlorobenzene/chlorocyclohexane mixture separation with excellent dual selectivity. Due to its unique dual/gemini conformational feature, not only chlorocyclohexane can be separated from chlorobenzene with exceeding 97% purity but also chlorobenzene can be separated from chlorocyclohexane with purity over 88%, and the dual selective fractionation process could be achieved in only one cycle of operation. Significantly, we demonstrate that the dual selectivity capability is essentially a competition of the stability between the guest-free and guest-loaded crystalline phases of geminiarene. We strongly believe that this work and the idea of multiple selective separation systems will open up new perspectives on macrocycle-based solid-state host-guest chemistry and molecular scale separation materials.

19.
Theranostics ; 9(11): 3075-3093, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31244942

RESUMO

With the rapid development of supramolecular chemistry and nanomaterials, supramolecular nanotheranostics has attracted remarkable attention owing to the advantages compared with conventional medicine. Supramolecular architectures relying on non-covalent interactions possess reversible and stimuli-responsive features; endowing supramolecular nanotheranostics based on supramolecular assemblies great potentials for the fabrication of integrated novel nanomedicines and controlled drug delivery systems. In particular, pillarenes, as a relatively new class of synthetic macrocycles, are important candidates in the construction of supramolecular therapeutic systems due to their excellent features such as rigid and symmetric structures, facile substitution, and unique host-guest properties. This review summarizes the development of pillarene-based supramolecular nanotheranostics for applications in biological mimicking, virus inhibition, cancer therapy, and diagnosis, which contains the following two major parts: (a) pillarene-based hybrid supramolecular nanotheranostics upon hybridizing with porous materials such as mesoporous silica nanoparticles, metal-organic frameworks, metal nanoparticles, and other inorganic materials; (b) pillarene-based organic supramolecular therapeutic systems that include supramolecular amphiphilic systems, artificial channels, and prodrugs based on host-guest complexes. Finally, perspectives on how pillarene-based supramolecular nanotheranostics will advance the field of pharmaceuticals and therapeutics are given.

20.
Org Lett ; 21(13): 5215-5218, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31247776

RESUMO

An anionic water-soluble leaning pillar[6]arene (AWLP6) has been synthesized and utilized as both the reductant and stabilizer for the one-pot synthesis of gold nanoparticles (AWLP6-AuNPs). Interestingly, AWLP6-AuNPs show not only optimal performance in self-assembly and label-free detection of methyl viologen, one of the most widely used herbicides, but also efficient catalytic activity for the hydrogenation of p-nitrophenol.

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