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1.
Chemistry ; 26(25): 5583-5591, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-31880368

RESUMO

As newly emerged crystalline porous materials, covalent organic frameworks (COFs) possess fascinating structures and some specific features such as modularity, crystallinity, porosity, stability, versatility, and biocompatibility. Besides adsorption/separation, sensing, catalysis, and energy applications, COFs have recently shown a promise in biomedical applications. This contribution provides an overview of the recent developments of COF-based medicines in cancer therapeutics, including drug delivery, photodynamic therapy (PDT), photothermal therapy (PTT), and combined therapy. Furthermore, the major challenges and developing trends in this field are also discussed. These recent developments are summarized and discussed to help encourage further contributions in this emerging and promising field.

2.
Chem Commun (Camb) ; 55(99): 14898-14901, 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31687688

RESUMO

We demonstrate herein an effective cascade reaction for combined photodynamic and starvation therapy in treating breast tumors based on a photosensitizer and CO prodrug decorated NMOF. The PDT-induced ROS can further trigger CO release, and the high antitumor efficiency derived from both 1O2 and CO is well confirmed by in vitro assays and in vivo trials.


Assuntos
Compostos de Boro/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Estruturas Metalorgânicas , Nanoestruturas , Fármacos Fotossensibilizantes/uso terapêutico , Monóxido de Carbono/química , Feminino , Humanos , Manganês/química , Pró-Fármacos/uso terapêutico , Oxigênio Singlete/química
3.
ACS Nano ; 13(11): 13304-13316, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31689082

RESUMO

Despite the excellent photodynamic and photothermal properties of organic molecular photosensitizers (PSs) and photothermal agents (PTAs), such as porphyrin and naphthalocyanine, their poor water solubility severely impedes their biological applications. Covalent organic frameworks (COFs), as an emerging class of organic crystalline porous materials, possess free active end groups (bonding defects) and large inner pores, which make them an ideal type of nanocarriers for loading hydrophobic organic molecular PSs and PTAs by both bonding defect functionalization (BDF) and guest encapsulation approaches to obtain multifunctional nanomedicines for PDT/PTT combination therapy. In this work, we report a nanoscale COF (NCOF) prepared via a facile synthetic approach under ambient conditions. Furthermore, a dual-modal PDT/PTT therapeutic nanoagent, VONc@COF-Por (3), is successfully fabricated by stepwise BDF and guest encapsulation processes. The covalently grafted porphyrinic PS (Por) and the noncovalently loaded naphthalocyanine PTA (VONc) are independently responsible for the PDT and PTT functionalities of the nanoagent. Upon visible (red LED) and NIR (808 nm laser) irradiation, VONc@COF-Por (3) displayed high 1O2 generation and photothermal conversion ability (55.9%), consequently providing an excellent combined PDT/PTT therapeutic effect on inhibiting MCF-7 tumor cell proliferation and metastasis, which was well evidenced by in vitro and in vivo experiments. We believe that the results obtained herein can significantly promote the development of NCOF-based multifunctional nanomedicines for biomedical applications.

4.
Dalton Trans ; 48(44): 16502-16508, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31528960

RESUMO

Although post-synthetic modification (PSM) has been successfully applied to NMOF decoration, only a handful of PSM-based single-crystal-to-single-crystal (SCSC) examples have been reported, particularly those involving multistep MOF-based SCSC transformations. In this contribution, three new MOFs, namely, UiO-68-NCS, UiO-68-R6G and UiO-68-R6G', were prepared via the single-crystal-to-single-crystal post-synthetic modification approach. For bioimaging, nanosized UiO-68-NCS, UiO-68-R6G, and UiO-68-R6G' were also prepared. Herein, nanosized UiO-68-R6G with a rhodamine-based fluorescence switch was found to be a highly sensitive and selective fluorescent probe for the detection of Hg2+ both in vitro and in vivo.

5.
Nat Plants ; 5(6): 616-625, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31182849

RESUMO

The lipid-derived hormone jasmonate (JA) regulates plant immunity and adaptive growth by triggering a genome-wide transcriptional programme. In Arabidopsis thaliana, JA-triggered transcriptional programming is largely orchestrated by the master transcription factor MYC2. The function of MYC2 is dependent on its physical interaction with the MED25 subunit of the Mediator transcriptional co-activator complex. Here we report the identification of JA enhancers (JAEs) through profiling the occupancy pattern of MYC2 and MED25. JA regulates the dynamic chromatin looping between JAEs and their promoters in a MED25-dependent manner, while MYC2 auto-regulates itself through JAEs. Interestingly, the JAE of the MYC2 locus (named ME2) positively regulates MYC2 expression during short-term JA responses but negatively regulates it during constant JA responses. We demonstrate that new gene editing tools open up new avenues to elucidate the in vivo function of enhancers. Our work provides a paradigm for functional study of plant enhancers in the regulation of specific physiological processes.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Ciclopentanos/metabolismo , Proteínas Nucleares/metabolismo , Oxilipinas/metabolismo , Transdução de Sinais , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Arseniato Redutases/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Cromatina/metabolismo , Proteínas de Ligação a DNA , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica de Plantas , Histonas/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica
6.
Inorg Chem ; 58(15): 9890-9896, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31241918

RESUMO

As an important type of reactive oxygen species (ROS), hypochloric acid (HClO) is closely linked with our daily life, and its convenient and rapid detection is very significant and imperative. Fluorescent and visual probes are being recognized as powerful and convenient tools for detection of ROS in the environment and living organisms by visualizing and imaging. In this contribution, a new metal-organic framework-based fluorescent probe UiO-68-PT, which was generated from a phenthiazine-decorated benzimidazole bridging dicarboxyl ligand and ZrCl4 under solvothermal conditions via in situ one-pot approach, is reported. The obtained UiO-68-PT features a unique HClO and Vitamin C-triggered reversible redox process, which is accompanied by both visual and fluorescence changes. Therefore, it can be a highly sensitive, specific, and reusable sensor to detect HClO species in water via both visual and fluorogenic observation (turn-on). Furthermore, its mixed membrane material (MMM) was fabricated by the combination of UiO-68-PT and poly(vinyl alcohol), and the obtained hydrophilic MMM can be used as a reversible colorimetric card for visual detection of the HClO in aqueous solution.

7.
iScience ; 14: 180-198, 2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-30981114

RESUMO

Covalent organic frameworks (COFs), an emerging class of organic porous materials, have attracted intense attention due to their versatile applications. However, the deliberate fabrication of COF-based nanomaterials for nanomedical application remains challenging due to difficulty in their size- and structure-controlled synthesis and poor aqueous dispersibility. Herein, we report two boron-dipyrromethene (BODIPY)-decorated nanoscale COFs (NCOFs), which were prepared by the Schiff-base condensation of the free end -CHO (bonding defects in COFs) on the established imine-based NCOFs with the amino-substituted organic photosensitizer BODIPY via "bonding defects functionalization" approach. Thus BODIPY has been successfully nanocrystallized via the NCOF platform, and can be used for photodynamic therapy (PDT) to treat tumors. These NCOF-based PDT agents featured nanometer size (∼110 nm), low dark toxicity, and high phototoxicity as evidenced by in vitro and in vivo experiments. Moreover, the "bonding defects functionalization" approach might open up new avenues for the fabrication of additional COF-based platforms for biomedical treatment.

9.
Chem Asian J ; 13(21): 3122-3149, 2018 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-30183134

RESUMO

Photodynamic therapy (PDT) is a highly effective, noninvasive, highly selective method for cancer treatment. Nanoscale metal-organic frameworks (NMOFs) are a type of crystalline hybrid material composed of metal centers and organic linkers. Owing to their adjustable structure, easy modification, permanent pores, and good biocompatibility, NMOFs, as either nanophotosensitizers or photosensitizer nanocarriers, have been used in PDT. In this article, we summarize the recent progress in MOF-based nanomaterials for tumor PDT. The MOF-based nanomaterials might open up new avenues for the fabrication of new types of photosensitizers for PDT.


Assuntos
Estruturas Metalorgânicas/química , Nanomedicina , Nanoestruturas/química , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Animais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Humanos , Estruturas Metalorgânicas/uso terapêutico , Neoplasias/patologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo
10.
Inorg Chem ; 57(16): 10137-10145, 2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30074794

RESUMO

We report herein a new ZIF-90-based PDT agent which was synthesized by in situ assembly of imidazole-2-carboxaldehyde (IcaH), Zn(NO3)2, and heavy atom iodine-attached Bodipy. The obtained 2I-BodipyPhNO2@ZIF-90 (1) host-guest photosensitive system featured low cytotoxicity, good biocompatibility, pH-driven selective cancer cell uptake and release, mitochondria targeting, and highly efficient pH-triggered 1O2 generation. Therefore, it can be used as a high-performing PDT agent to selectively kill tumor cells. In comparison to free 2I-BodipyPhNO2, 1 exhibits a much higher antitumor efficacy and selectivity, which was confirmed by in vitro cell experiments.


Assuntos
Antineoplásicos/farmacologia , Compostos de Boro/farmacologia , Estruturas Metalorgânicas/farmacologia , Nanopartículas/química , Fármacos Fotossensibilizantes/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/efeitos da radiação , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Compostos de Boro/síntese química , Compostos de Boro/efeitos da radiação , Compostos de Boro/toxicidade , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/efeitos da radiação , Estruturas Metalorgânicas/toxicidade , Mitocôndrias/metabolismo , Nanopartículas/efeitos da radiação , Nanopartículas/toxicidade , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/efeitos da radiação , Fármacos Fotossensibilizantes/toxicidade , Oxigênio Singlete/metabolismo
11.
Chemistry ; 24(56): 15096-15103, 2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30016561

RESUMO

Introducing phenylphosphonic acid (H2 PPA) into the Ag/tBuSH assembly system has produced a family of nanoscale-sized, high-atom number, silver thiolate/PPA nests (SD/Ag45 a, SD/Ag66 a, and SD/Ag73 a) with impressive core-shell features. SD/Ag45 a is a 45-atom ellipsoid comprised of an Ag36 shell trapping an Ag9 S2 three-bladed rotor inside. SD/Ag66 a comprises an inner rod-like Ag20 core and an outer Ag44 shell, giving a 64-atom nest. These Ag64 nests are further extended by Ag(CN)2 linkers to form a one-dimensional chain structure. SD/Ag73 a is a three-shell 73-nucleus silver nest with a central silver atom enclosed in a rhombicuboctahedron of 24 silver atoms, which is itself enclosed in the outermost shell of a rectified version of a 48-Ag octahedral Goldberg 2,0 cage. The solution behaviors and optical absorption properties of the three nests are described in detail. Of note, SD/Ag45 a and SD/Ag73 a emit in the near-infrared region and show different luminescent thermochromic behavior. This work demonstrates that the participation of H2 PPA strongly influences the structures of silver thiolate nests, thus providing a new route to fabricate and modify them in a more rational way.

12.
Chem Commun (Camb) ; 54(35): 4461-4464, 2018 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-29658038

RESUMO

A 90-nucleus silver cluster (SD/Ag38) cocapped by tBuC6H4S- and PhCOO- ligands was synthesized using hetero-anion template method. Single-crystal X-ray diffraction (SCXRD) revealed a 90-nucleus metallic dumbbell-like core constructed by two large W5O19@Ag38 heads sandwiching one slender (SO4)2@Ag14 waist. Both W5O198- and SO42- templates were in situ generated and synergistically induced the formation of the largest known anion-templated silver cluster. Although SD/Ag38 is emission-silent at room temperature, increasingly brighter near-infrared (NIR) emission at ca. 742 nm was detected on cooling from 293 to 93 K.

13.
Inorg Chem ; 57(6): 3169-3176, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29488754

RESUMO

Herein, we report an iodine-attached Zn(II)-porphyrinic dicarboxylic building block (ZnDTPP-I2-2H, 1) that can be introduced into UiO-66 NMOF via one-pot synthetic approach to generate a new ZnDTPP-I2 doped UiO-66 type nano metal-organic framework (NMOF) of ZnDTPP-I2⊂UiO-66 (2). Compared to its homologous iodine-free NMOF of ZnDTPP⊂UiO-66 (4), ZnDTPP-I2⊂UiO-66 (2) with heavy iodine atoms is a more effective nanosized photosensitizer for singlet oxygen generation under physiological conditions. As expected, 2 displayed a high photodynamic therapy efficacy for treatment of liver cancer cells in vitro.


Assuntos
Estruturas Metalorgânicas/farmacologia , Metaloporfirinas/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/efeitos da radiação , Estabilidade de Medicamentos , Células Hep G2 , Humanos , Luz , Luminescência , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/efeitos da radiação , Metaloporfirinas/síntese química , Metaloporfirinas/química , Metaloporfirinas/efeitos da radiação , Nanopartículas/química , Nanopartículas/efeitos da radiação , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Oxigênio Singlete/química , Zinco/química , Zircônio/química
14.
Chem Commun (Camb) ; 54(19): 2361-2364, 2018 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-29450419

RESUMO

A discrete 78-nucleus silver-sulfur nanocluster with a sulfate-centered multishell structure was isolated and characterized. Its crystal structure revealed 18 and 60 Ag atoms in the inner and outer shell, respectively. The inner shell of 18-nuclearity Ag atoms is a very rare convex polyhedron featuring an elongated triangular orthobicupola. The incorporation of a sulfate anion and multishell arrangement in the nanocluster led to a dramatic decrease in the band gap (Eg = 1.40 eV). Our study showed that simple anions can also induce the formation of high-nuclearity silver clusters with excellent optical properties.

15.
Chemistry ; 24(19): 4967-4972, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29380899

RESUMO

Compared with the well-known anion-templated effects in shaping silver thiolate clusters, the influence from the organic ligands in the outer shell is still poorly understood. Herein, three new benzoate-functionalized high-nuclearity silver(I) thiolate clusters are isolated and characterized for the first time in the presence of diverse anion templates such as S2- , α-[Mo5 O18 ]6- , and MoO42- . Single-crystal X-ray analysis reveals that the nuclearities of the three silver clusters (SD/Ag28, SD/Ag29, SD/Ag30) vary from 32 to 38 to 78 with co-capped tBuS- and benzoate ligands on the surface. SD/Ag28 is a turtle-like cluster comprising a Ag29 shell caging a Ag3 S3 trigon in the center, whereas SD/Ag29 is a prolate Ag38 sphere templated by the α-[Mo5 O18 ]6- anion. Upon changing from benzoate to methoxyl-substituted benzoate, SD/Ag30 is isolated as a very complicated core-shell spherical cluster composed of a Ag57 shell and a vase-like Ag21 S13 core. Four MoO42- anions are arranged in a supertetrahedron and located in the interstice between the core and shell. Introduction of the bulky benzoate changes elaborately the nuclearity and arrangements of silver polygons on the shell of silver clusters, which is exemplified by comparing SD/Ag28 and a known similar silver thiolate cluster. The three new clusters emit luminescence in the near-infrared (NIR) region and show different thermochromic luminescence properties. This work presents a flexible approach to synthetic studies of high-nuclearity silver clusters decorated by different benzoates, and structural modulations are also achieved.

16.
Front Chem ; 6: 649, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30687696

RESUMO

In order to further improve the photocatalytic performance of BiFeO3 (BFO), novel Au-induced hierarchical nanofibers/nanoflakes structured BiFeO3 homojunctions (Au x -BFO, x = 0, 0. 6, 1.2, 1.8, 2.4 wt%) were in situ synthesized through a simple reduction method with assist of sodium citrate under the analogous hydrothermal environment. The effect of loading amount of Au nanoparticles (NPs) on the physicochemical properties and photocatalytic activity was investigated in detail. The Au1.2-BFO NFs sample show the best photocatalytic activity (85.76%), much higher than that for pure BFO samples (49.49%), mainly due to the hierarchical nanofibers/nanoflakes structured homojunction, the surface plasmon resonance (SPR) effect of Au NPs, as well as the presence of defects (Fe2+/Fe3+ pairs and oxygen vacancy). Furthermore, the possible formation mechanism of the unique homojunction and the enhanced photocatalytic mechanism for the degradation of methylene blue (MB) dye are proposed. It is proven that holes (h+) play the decisive role in the photocatalytic process. The present work provides a fascinating way to synthesize efficient homojunctions for the degradation of organic pollutes.

17.
Inorg Chem ; 56(21): 13241-13248, 2017 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-28985071

RESUMO

Fluorescent probes are powerful tools for the investigations of reactive oxygen species (ROS) in living organisms by visualization and imaging. As one of the most important of the natural reactive oxygen species (ROS), hypochlorous acid (HClO) plays a crucial role in various physiological and pathological processes. We report herein a new redox-switchable NMOF of UiO-68-ol via a direct ligand modification approach. The obtained UiO-68-ol NPs, which contains organic-based molecular redox switches, exhibit excellent photophysical properties for biological application and can be highly sensitive and selective fluorescent probes to detect HClO species in living cells.


Assuntos
Portadores de Fármacos/farmacologia , Corantes Fluorescentes/farmacologia , Ácido Hipocloroso/análise , Estruturas Metalorgânicas/farmacologia , Nanopartículas/química , Compostos de Urânio/química , Animais , Linhagem Celular Tumoral , Cisteína/metabolismo , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Hidrazinas/metabolismo , Ligantes , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Camundongos , Microscopia Confocal/métodos , Imagem Molecular , Oxirredução , Porosidade
18.
Inorg Chem ; 56(14): 8341-8347, 2017 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-28650625

RESUMO

A CuI-loaded and n-pentadecyl-attached imidazolium salt decorated UiO-67-type metal-organic framework (CuI@UiO-67-IM, 2) based on a new premodified ligand L (n-pentadecyl-attached imidazolium (IM) decorated dicarboxylic acid) and ZrCl4 is reported. Compound 2 can be a bifunctional composite heterogeneous phase-transfer catalyst to promote the azide-alkyne cycloaddition (H2O, air, 80 °C) from corresponding halogenated compounds and sodium azide as a sequential one-pot procedure with high yields and excellent regioselectivity.

19.
Inorg Chem ; 56(4): 2337-2344, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28182424

RESUMO

A bifunctional robust and highly porous imidazolium-based ionic liquid decorated UiO-67 type MOF (UiO-67-IL, 1) was successfully constructed via solvothermal assembly of the imidazolium-based ligand and Zr(IV) ions. It exhibits a highly selective adsorption for CO2 over CH4 and N2. Furthermore, 1 herein can be used as a highly active heterogeneous catalyst for CO2 cycloaddition with epoxides under atmospheric pressure with or without cocatalyst TBAB (n-Bu4NBr).

20.
Chem Commun (Camb) ; 52(98): 14113-14116, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27858003

RESUMO

Drug delivery systems with targeting agents for precise drug release in cancer therapy are very significant and important. Herein, we report the rational design and synthesis of a DOX (doxorubicin) loaded UiO-68-type of nanoscale metal-organic framework (NMOF) with a tumor targeting agent (folic acid, FA), DOX@UiO-68-FA (3), as a multifunctional drug delivery system for hepatoma (Hep G2) therapy via tail-vein injection. Compared to free DOX, FA-unloaded DOX@Mi-UiO-68 (2), 3 exhibits a much higher antitumor efficacy, which was confirmed by cell imaging, standard 3-(4,5-dimethylthiahiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) proliferation and in vivo experiments.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Doxorrubicina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Nanopartículas/química , Compostos Organometálicos/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/patologia , Camundongos , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Relação Estrutura-Atividade
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