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1.
J Mater Chem B ; 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32195527

RESUMO

Organic phototheranostic nanomedicines with an optimized near-infrared (NIR) biological transparent window (700-900 nm) are highly desirable for the diagnosis and treatment of deep-seated tumors in clinic. As excellent organic photosensitizers for photodynamic therapy (PDT) with outstanding photo- and thermo-stability, phthalocyanines (Pcs) have been used as the building blocks of single-component nanomedicines. However, to the best of our knowledge, all the Pc-based single-component self-assemblies reported to date are of an H-aggregate nature. This results in the simultaneous self-quenching of fluorescence emission and photodynamic activity as well as greatly reduced tissue penetration due to blue-shifted absorption. In the present work, intramolecular hydrogen bonding was formed between the two long and flexible axial NH2-terminated diethylene glycol ligands of the amphiphilic SiPc molecule (SiPc-NH2) in solution, leading to the employment of a cis-conformation of this molecule according to the 1H-NMR spectroscopy result, which as a building block then further self-assembled into monodisperse nanospheres (SiPcNano) with a J-aggregation nature on the basis of electronic absorption spectroscopic results. As a result, SiPcNano exhibited significantly enhanced red-shifted absorption in the NIR range of 750-850 nm and fluorescence emission. This in combination with the increased photodynamic effect for SiPcNano triggered by the protonation of amine groups due to the acidic nature of tumors endowed effective synergistic NIR photodynamic and photothermal effects in different cancer cells and thus effective inhibition of tumor growth in A549 tumor-bearing mice on the basis of a series of in vitro and in vivo evaluations. The present result provides a new approach for constructing novel single-component NIR organic nanomedicines for multifunctional cancer therapy.

2.
Chem Commun (Camb) ; 56(4): 527-530, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31829346

RESUMO

Towards mimicking natural photosystems, supramolecular gels containing two types of porphyrins were developed for photocatalysis. Protonation and J-aggregation of porphyrins within gels expand the absorption to a wide range of visible wavelengths. Porphyrin exciplex formation renders a smaller bandgap for photo-induced electron generation. These features induce effective photocatalytic hydrogen generation.

3.
Chem Commun (Camb) ; 56(5): 703-706, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31845686

RESUMO

We report the development of a new type of organic semiconductor gas sensor based on a porphyrin-based hydrogen-bonded organic framework (HOF). Owing to the orderly porous structures, the decoration with rich amino sites and the n-type semiconductor nature, this HOF-based sensor exhibits selective NO2 sensing performance with ultra-fast response/recovery rates (17.6 s/15.4 s over 100 ppb) and a limit of detection lower than 40 ppb, together with high sensitivity, good reproducibility, and long-term stability at room temperature. This study demonstrates that HOF-based materials have potential application prospects in gas sensing, thereby offering a new way of thinking for the design and development of sensors.

4.
Chem Commun (Camb) ; 56(5): 798-801, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31848528

RESUMO

Catalysts composed of isolated single Fe atoms coordinated to graphitic carbon nitride (g-C3N4) dispersed on hierarchical porous N-doped carbon polyhedra (Fe-g-C3N4/HPNCPs) were successfully prepared. The optimized catalyst, Fe-g-C3N4/HPNCP-0.8, showed excellent electrocatalytic activity for the oxygen reduction reaction under alkaline conditions with a half-wave potential of 0.902 V, significantly outperforming commercial Pt/C, as well as high durability. The high performance stems from the synergistic effect of the atomically dispersed Fe-N2 sites and the advantages of the hierarchical porous structure for promoting mass transport and improving the accessibility of the active sites.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31833627

RESUMO

Ordered and flexible porous frameworks with solution processability are highly desirable to fabricate continuous and large-scale membranes for the efficient gas separation. Herein, the first microporous hydrogen-bonded organic framework (HOF) membrane has been fabricated by an optimized solution-processing technique. The framework exhibits the superior stability because of the abundant hydrogen bonds and strong π-π interactions. Thanks to the flexible HOF structure, the membrane possesses the unprecedented pressure-responsive H2 /N2 separation performance. Furthermore, the scratched membrane can be healed by the treatment of solvent vapor, achieving the recovery of separation performance.

6.
Chem Sci ; 10(35): 8246-8252, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31673325

RESUMO

Photothermal therapy in the second near-infrared window (NIR-II, 1000-1700 nm) exhibits a significant advantage over the first near-infrared window (NIR-I, 650-950 nm) in terms of both maximum permissible exposure (MPE) and penetration depth. However, the thus far reported NIR-II photothermal agents (PTAs) have been focused just on inorganic semiconducting and organic polymeric semiconducting nanoparticles. Herein a novel cruciform phthalocyanine pentad was designed, synthesized, and characterized for the first time. The water-soluble nanoparticles (Zn4-H2Pc/DP NPs) assembled from this single molecular material with the help of DSPE-PEG2000-OCH3 exhibit characteristic absorption in the NIR-II region at 1064 nm with a large extinction coefficient of 52 L g-1 cm-1, high photothermal conversion efficiency of 58.3%, and intense photoacoustic signal. Moreover, both in vitro and in vivo studies reveal the good biocompatibility and notable tumor ablation ability of Zn4-H2Pc/DP NPs under 1064 nm laser irradiation. Theoretical density functional theory calculations interpret the two-dimensional compressional wave energy-dissipation pathway over the broad saddle curved framework of the cruciform conjugated phthalocyanine pentad, rationalizing the efficient photothermal properties of corresponding Zn4-H2Pc/DP NPs in the NIR-II window.

7.
ACS Appl Mater Interfaces ; 11(48): 45118-45125, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31713412

RESUMO

Metal-organic frameworks (MOFs) are powerful toolkits to directly correlate structure-function relationships due to their well-defined structures. In this work, 5,15-di(3,4,5-trihydroxyphenyl)porphyrin (DTPP) and 5,10,15,20-tetra(3,4,5-trihydroxyphenyl)porphyrin (TTPP) are reacted with zirconium ions to afford two MOFs (Zr-DTPP and Zr-TTPP) with acid and base tolerance in the pH range of 1.0-14.0. Powder X-ray diffraction investigation combined with Rietveld refinement reveals the J-aggregated porphyrin building blocks confined by benzene-1,2,3-trisolate-zirconium chains in the newly prepared Zr-DTPP. Electron spin-resonance, singlet-oxygen determination, and sulfides oxidation experiments demonstrate a much better singlet-oxygen evolution of J-aggregated Zr-DTPP than that of unaggregated Zr-TTPP reported previously, in good contrast to the weaker photocatalytic capability disclosed for DTPP than that for TTPP in solution, consummating the theory of photosensitizer J-aggregation in boosting heterogeneous photoinduced singlet-oxygen generation.

8.
Chemistry ; 25(71): 16207-16213, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31602719

RESUMO

The functionalization of natural 1D architectures is dependent on hierarchically inner nanostructures. However, the artificial supramolecular nanofibers or nanotubes were rarely developed with complex inner structures. Inspired by a biomimetic strategy, single-molecule-diameter nanofibers of double-decker phthalocyanine (EuPc2) with compartmentalized internal space and fantastic electrochemical features were developed upon air/water interfacial assembly with poly-l-lysine. EuPc2/poly-l-lysine nanofibers can be electrochemical sensors both in water and the gas phase and have the best analytical performances for nitrite among all the porphyrins or phthalocyanines monomers and assemblies. Imbedding nitrite in compartments not only promotes the sensing but also changes the supramolecular chirality of nanofibers, and the morphological-dependent sensing properties of EuPc2 assemblies in water are different from that in the gas phase. These results suggest the unprecedented properties for diverse applications of artificial 1D architectures containing complex inner nanostructures.

9.
J Am Chem Soc ; 141(43): 17431-17440, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31608638

RESUMO

Fabricating ultrathin two-dimensional (2D) covalent organic framework (COF) nanosheets (NSs) in large scale and high yield still remains a great challenge. This limits the exploration of the unique functionalities and wide range of application potentials of such materials. Herein, we develop a scalable general bottom-up approach to facilely synthesize ultrathin (<2.1 nm) imine-based 2D COF NSs (including COF-366 NSs, COF-367 NSs, COF-367-Co NSs, TAPB-PDA COF NSs, and TAPB-BPDA COF NSs) in large scale (>100 mg) and high yield (>55%), via an imine-exchange synthesis strategy through adding large excess amounts of 2,4,6-trimethylbenzaldehyde into the reaction system under solvothermal conditions. Impressively, visualization of the periodic pore lattice for COF-367 NSs by a scanning tunneling microscope (STM) clearly discloses the ultrathin 2D COF nature. In particular, the ultrathin COF-367-Co NSs isolated are subject to the heterogeneous photocatalyst for CO2-to-CO conversion, showing excellent efficiency with a CO production rate as high as 10 162 µmol g-1 h-1 and a selectivity of ca. 78% in aqueous media under visible-light irradiation, far superior to corresponding bulk materials and comparable with the thus far reported state-of-the-art visible-light driven heterocatalysts.

10.
Angew Chem Int Ed Engl ; 58(50): 18011-18016, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31559679

RESUMO

The imine condensation reaction of 5,5'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)diisophthalaldehyde with cyclohexanediamine resulted in a shape-persistent multifunctional tubular organic cage (MTC1). It exhibits selective fluorescence sensing towards divalent Pd ions with a very low detection limit (38 ppb), suggesting effective complexation between these two species. Subsequent reduction of MTC1 and Pd(OAc)2 with NaBH4 afforded a cage-supported catalyst with well-dispersed ultrafine Pd nanoparticles (NPs) in a narrow size distribution (1.9±0.4 nm), denoted as Pd@MTC1-1/5. Such ultrafine Pd NPs in Pd@MTC1-1/5, in cooperation with photocatalytically active MTC1, enable efficient sequential reactions involving visible light-induced aerobic hydroxylation of 4-nitrophenylboronic acid to 4-nitrophenol and the following hydride reduction with NaBH4 . This is the first example of a multifunctional organic cage capable of sensing, directing nanoparticle growth, and catalyzing sequential reactions.

11.
Dalton Trans ; 48(40): 14989-14995, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31498343

RESUMO

Designing photocatalysts with heterostructures is an effective way to promote visible-light-driven photocatalytic degradation. Herein, a series of 2D/2D heterojunction photocatalysts, denoted as CuPor-Ph-COF/g-C3N4 composites, were prepared through in situ synthesis on the surface of g-C3N4 by a facile liquid-assisted grinding method. The photocatalytic performance of the as-prepared CuPor-Ph-COF/g-C3N4 composites was evaluated by the degradation of a model pollutant rhodamine B. The CuPor-Ph-COF/g-C3N4 composites displayed superior photocatalytic performance to pure g-C3N4 or pure CuPor-Ph-COF because of the faster separation of photogenerated charges. This represents the first composite fabricated between a 2D porphyrin-based covalent organic framework (COF) and g-C3N4, demonstrating not only the possibility but also more importantly the affordability of the application of costly porphyrin-based COFs in catalysis.

12.
Ultrason Sonochem ; 58: 104648, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31450373

RESUMO

We report the preparation of a porous and hierarchical manganese(III) oxide tiny nanostructures (Mn2O3 TNS) by a simple sonochemical approach. The nanocatalyst was synthesized by a bath-type ultrasound washer (Honda Electronics, W-118T) at 700 W and 300 kHz frequency. The morphology and chemical composition of the nanocatalyst were characterized by X-rays diffractometry (XRD), transmission electron microscopy (TEM), energy dispersive x-rays (EDX), X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS). The electrocatalytic activity (ECA) was monitored by detection of toxic antibiotic drug (chloramphenicol) under phosphate buffer (pH 7.0). A facile sonochemical route was employed to prepare Mn2O3 TNS modified electrode. The screen-printed carbon electrode (SPCE) modified with Mn2O3 TNS was fabricated and applied for the electrochemical determination of chloramphenicol. Compared with bare SPCE, Mn2O3 TNS modified SPCE showed highest current response towards chloramphenicol. Furthermore, the modified sensor exhibits with a sharp peak and two linear ranges by using DPV (i) 0.015-1.28 µM with the sensitivity of 4.167 µA µM-1 cm-2 and (ii) 1.35-566.3 µM with the sensitivity of 7.205 µA µM-1 cm-2. Notably, we achieved a very low-level detection limit of 4.26 nM for the DPV detection of chloramphenicol. Further, the superior practicability of the nanosheets modified sensor can be used for real time sensing of chloramphenicol with good recover ranges.


Assuntos
Cloranfenicol/análise , Análise de Alimentos/métodos , Limite de Detecção , Compostos de Manganês/química , Leite/química , Nanoestruturas/química , Óxidos/química , Ondas Ultrassônicas , Animais , Antibacterianos/análise , Antibacterianos/química , Catálise , Cloranfenicol/química , Eletroquímica , Contaminação de Alimentos/análise , Concentração de Íons de Hidrogênio , Cinética
13.
Top Curr Chem (Cham) ; 377(3): 18, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31161309

RESUMO

Manganese(III) porphyrin complexes with various metal-containing/non-metal bridges reported during the past two decades, including their structural characteristics and magnetic properties, are summarized. As the porphyrin ligands usually adopt a planar chelate form, it is possible that the porphyrin-based complexes, being a coordination-acceptor building block, have two coordination labile sites in trans positions. In particular, the coordination labile sites in an octahedral field face the direction of the Jahn-Teller elongated axis occupying the dz2 orbital. As a result of this characteristic orbital arrangement, the activity and magnetic-electronic properties of the manganese complexes can be tuned by modulating the porphyrin ligand, which is equatorially located around the manganese ion and coupled with the dx2-y2 orbital. The high-spin Mn(III) porphyrin complexes (S = 2) display strong magnetic uniaxial anisotropy with the Jahn-Teller axis as the magnetic easy axis. So far, various manganese(III) porphyrin magnetism systems, including multinuclear clusters, one-dimensional chains, and two- or three-dimensional networks, have been designed and structurally and magnetically characterized. This review shows that the manganese(III) porphyrin complexes have potential as versatile sources for the design of unique magnetic materials as well as other molecular functional materials with various structures.


Assuntos
Imãs/química , Metaloporfirinas/química , Complexos de Coordenação/química , Cristalografia por Raios X , Cianetos/química , Dimerização , Magnetismo/métodos , Modelos Moleculares
14.
Front Chem ; 7: 336, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31157209

RESUMO

Supramolecular gels containing porphyrins and phthalocyanines motifs are attracting increased interests in a wide range of research areas. Based on the supramolecular gels systems, porphyrin or phthalocyanines can form assemblies with plentiful nanostructures, dynamic, and stimuli-responsive properties. And these π-conjugated molecular building blocks also afford supramolecular gels with many new features, depending on their photochemical and electrochemical characteristics. As one of the most characteristic models, the supramolecular chirality of these soft matters was investigated. Notably, the application of supramolecular gels containing porphyrins and phthalocyanines has been developed in the field of catalysis, molecular sensing, biological imaging, drug delivery and photodynamic therapy. And some photoelectric devices were also fabricated depending on the gelation of porphyrins or phthalocyanines. This paper presents an overview of the progress achieved in this issue along with some perspectives for further advances.

15.
J Am Chem Soc ; 141(22): 8737-8740, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31117661

RESUMO

Hydrogen-bonded organic framework (HOF)-based catalysts still remain unreported thus far due to their relatively weak stability. In the present work, a robust porous HOF (HOF-19) with a Brunauer-Emmett-Teller surface area of 685 m2 g-1 was reticulated from a cagelike building block, amino-substituted bis(tetraoxacalix[2]arene[2]triazine), depending on the hydrogen bonding with the help of π-π interactions. The postsynthetic metalation of HOF-19 with palladium acetate afforded a palladium(II)-containing heterogeneous catalyst with porous hydrogen-bonded structure retained, which exhibits excellent catalytic performance for the Suzuki-Miyaura coupling reaction with the high isolation yields (96-98%), prominent stability, and good selectivity. More importantly, by simple recrystallization, the catalytic activity of deactivated species can be recovered from the isolation yield 46% to 92% for 4-bromobenzonitrile conversion at the same conditions, revealing the great application potentials of HOF-based catalysts.

16.
ACS Appl Mater Interfaces ; 11(12): 11466-11473, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30821143

RESUMO

As a vital biological mediator and a widely used industrial oxidant, the accurate detection of hydrogen peroxide (H2O2) is of significance for both academic purpose and practical applications. Herein, we report a novel approach for the development of a high-performance electrochemical H2O2 sensor constructed by iron phthalocyanine (FePc)-based diyne-linked conjugated polymeric nanosheets (NSs), FePc-CP NSs. The FePc-CP NSs were delaminated from the bulk material via a defect- and disorder-induced synthetic strategy. By the quasi-Langmuir-Shäfer method, the prepared FePc-CP NSs were self-assembled into multilayer films with controllable thickness on electrodes. Owing to the highly exposed active centers on the surfaces, the FePc-CP NS film-modified electrodes exhibited excellent H2O2 determination performance with a wide linear detection range (0.1-1000 µM), a short response time (the response current approached the maximum value within 0.1 s), a low limit of detection (0.017 µM), and excellent sensitivity (97 µA cm-2 mM-1), which are comparable to the best results reported so far for electrochemical H2O2 sensors. In addition, the fabricated electrochemical H2O2 sensor also displayed satisfactory stability, reproducibility, and selectivity. Furthermore, the obtained FePc-CP NS film sensor can be applied in real-time monitoring of H2O2 in commercial orange juice and beer as well as H2O2 secreted from A549 live cells, revealing its application potential toward the accurate detection of H2O2 in real-sample analysis.

17.
Inorg Chem ; 58(4): 2422-2429, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30721033

RESUMO

For the purpose of further exploring the effect of nonperipherally attached substituents on single-ion magnet (SIMs) performance, tetrasubstituted bis[1,8,15,22-tetrakis(3-pentyloxy)phthalocyaninato]terbium double-deckers, in both the reduced form TbH[Pc(α-OC5H11)4]2 (1) and the neutral form Tb[Pc(α-OC5H11)4]2 (2), were prepared. Single-crystal X-ray diffraction analysis for 2 unambiguously demonstrates the pinwheellike molecular structure with C4 symmetry. Magnetic investigations of the two bis(phthalocyaninato)terbium double-deckers reveal their characteristic SIM nature. 2 exhibits SIM performance superior to that of 1, as revealed by the larger energy barrier of 466 K for the former species and 431 K for the latter species due to the presence of organic radical-f (radical-Tb) interactions. The enhanced SIM performance of 2 in comparison to 1 actually stems from the presence of radical-f interactions and an enhanced ligand field strength. The latter positive factor is indicated by the electrostatic potential around the terbium ion on the basis of density functional theory (DFT) calculations.

18.
Dalton Trans ; 48(5): 1586-1590, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30607410

RESUMO

Reversibly switched reduced protonated and neutral unprotonated forms of chiral mixed (phthalocyaninato)(porphyrinato) double-decker compounds were achieved, and comparative investigation over their magnetic properties firstly discovered that the introduction of f-radical interaction has a negative impact on enhancing the performance of SMMs.

19.
Chem Commun (Camb) ; 55(9): 1201-1204, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30534759

RESUMO

The first polyoxometalate (POM)-containing nanocage based metal-organic framework (Zn-POMCF) was synthesized by a surfactant-assisted method. In contrast to the Zn-based metal-organic framework (Zn-MOF), the cooperative assembly of POM and a Zn/trz macrocycle gave rise to high stability and good electrochemical ability of the Zn-POMCF in lithium-ion batteries (LIBs).

20.
Dalton Trans ; 48(2): 718-727, 2019 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-30560248

RESUMO

A calix[4]arene (C4A)-functionalized (phthalocyaninato)(porphyrinato) europium(iii) triple-decker compound (Pc)Eu(Pc)Eu[T(C4A)PP] (1) is firstly designed, synthesized and prepared into well-organized films using a simple solution-processing quasi-Langmuir-Shäfer (QLS) method. The QLS film of 1 on an ITO (film 1/ITO) electrode, serving as a host-guest electrochemical recognition layer, is able to establish specific responses/interactions toward organic molecules with biological and drug interest including dopamine (DA), uric acid (UA), tyrosine (Tyr), tryptophan (Trp) and Acetaminophen (APAP), depending mainly on the matching degree of molecular dimensions between the analytes and the C4A cavity in addition to their chemical nature. More significantly, the film 1/ITO electrode shows a wide linear range of electrochemical detection (from 0.1 to 100 µM) to DA and APAP, with a high sensitivity of 53.0 and 94.3 µA mM-1 and a very low detection limit of 25 and 11 nM for DA and APAP, respectively, representing the best result among the nonenzymatic organic semiconductor-based biosensors. In particular, the film 1/ITO electrode exhibits excellent stability, reproducibility, high selectivity, and anti-interference nature for the detection of both DA and APAP, indicating the great potential of calix[n]arene macrocycle-modified tetrapyrrole rare earth sandwich compounds in the field of ultrasensitive and specific nonenzymatic sensors.

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