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1.
J Photochem Photobiol B ; 222: 112274, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34330082

RESUMO

Photodynamic therapy (PDT) has gained much attention in tumor therapy because of its special advantages. PDT heavily depends on the oxygen, yet the tumor microenvironment (TME) is a hypoxic and acid milieu, which weakens the PDT effect. Based on the consideration that the TME deteriorated by the PDT oxygen consumption could activate the hypoxic-sensitive small-molecule drug, we designed and prepared an integrated nanocomposite including zirconium ion metal organic framework (carrier), pyropheophorbide-a (PPa, photosensitizer), and 6-amino flavone (AF, hypoxic-sensitive drug), aiming to exert a cascaded PDT-chemotherapy (CT) antitumor effect and to solve the hypoxic challenge. The prepared nanocomposite showed great stability under the physiological (pH 7.4) condition and could continuously release PPa and AF under slightly acidic pH condition (pH 6.4), suggesting a tumor microenvironment responsive feature. Systematical in vitro and in vivo researches under various conditions (light, dark, hypoxic and normoxic) have showed that the obtained Zr-MOF@PPa/AF@PEG nanoparticles (NPs) had good biocompatibility and could achieve efficient antitumor effects based on PDT- chemotherapy (CT) cascade process. Finally, bright red fluorescence was observed in the tumor cells after internalization implying an application potential in tumor imaging.


Assuntos
Clorofila/análogos & derivados , Flavonoides/química , Estruturas Metalorgânicas/química , Nanocompostos/química , Fotoquimioterapia/métodos , Nanomedicina Teranóstica , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Clorofila/química , Clorofila/metabolismo , Clorofila/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Flavonoides/metabolismo , Flavonoides/uso terapêutico , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanocompostos/uso terapêutico , Nanocompostos/toxicidade , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Polietilenoglicóis/química , Oxigênio Singlete/metabolismo , Microambiente Tumoral , Zircônio/química
2.
J Chromatogr A ; 1637: 461829, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33383244

RESUMO

A gallic acid-affinity molecularly imprinted polymer (G-MIP) was first used as an adsorbent for selective identification and capture of luteolin (LTL) in herbal medicine samples. The G-MIP was prepared by using LTL as the template, gallic acid (GA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the crosslinking agent, and 2,2'-azobis(2-methylpropionitrie) (AIBN) as the initiator. The properties of G-MIP were characterized by FT-IR, transmission electron microscope, scanning electron microscope, dynamic light scattering, specific surface area, and X-ray photoelectron spectrum. The adsorption conditions were optimized, and the adsorption equilibrium model and adsorption kinetics model of the adsorbent were investigated under the best experimental conditions. The saturated adsorption capacity is 1.24 mg g-1, which is not only higher than the adsorption capacity of 4-carboxyphenylboronic acid-affinity MIP adsorbent but also superior to those of many reported adsorbents for enriching of LTL. The LTL was quantified by HPLC. The linear range is 0.05-100 mg L-1, the detection limit is 0.020 mg L-1. This method was successfully applied in the selective recognition of LTL in herbal medicines with recoveries of 93.9-114.2%, and the relative standards deviations (RSDs) are 0.4-5.6%. Thus, this work provides a potential possibility and practical platform for the determination of LTL in complex matrices.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácido Gálico/química , Luteolina/análise , Polímeros Molecularmente Impressos/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Bioorg Med Chem Lett ; 29(22): 126730, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31607609

RESUMO

Cyclic peptides combine several favorable properties such as good binding affinity, target selectivity and low toxicity that make them an attractive modality for drug development. In an effort to identify what conformation could be accounting for the bioactive disparity of natural and synthetic cyclic peptides, some structurally-constrained analogs of cyclopeptide Axinastatin 3 were prepared by photo-induced single electron transfer (SET) reaction. Detailed stereochemistry study was performed by experimental electronic circular dichroism combined with theoretical calculations. Our study suggested that the cyclopeptide 1 with ßI-turn presented stronger antitumor activity comparing with those without such secondary structures. Moreover, a rare 'π helix unit' (compound 3) was realized because of the constrained cyclic structure, which could be considered an important research object for future study of unique helix secondary structures.


Assuntos
Peptídeos Cíclicos/farmacologia , Animais , Antineoplásicos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Transporte de Elétrons , Fibroblastos/efeitos dos fármacos , Humanos , Camundongos , Modelos Moleculares , Conformação Molecular , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/química , Processos Fotoquímicos , Estereoisomerismo , Relação Estrutura-Atividade
4.
Dalton Trans ; 48(27): 10151-10159, 2019 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-31185070

RESUMO

In recent years, organic-inorganic hybrid metal halides have emerged as a highly promising class of semiconducting light emitting diodes (LEDs) due to their fascinating photoluminescence properties. Here, by specifically selecting different organic cations as templates, a series of new hybrid cuprous halides have been solvothermally prepared, namely [Me-Py]CuI2 (1), [(Me)2-DABCO]Cu2I4 (2), [Me-MePy]Cu2I3 (3), and [H2DABCO]Cu3X5 (X = I (4) and Br (5)). These hybrid cuprous halides feature one-dimensional (1D) [CuI2]-, [Cu2I3]- and [Cu3X5]2- (X = Br, I) chains surrounded and charge-balanced by organic cations. Under UV photoexcitation, these hybrid cuprous halides exhibit strong tunable photoluminescence from cyan (480 nm) to red (675 nm) emissions with large Stokes shifts (345 nm). The intrinsic nature of PL emissions is also investigated based on temperature-dependent PL emission, lifetime, photoluminescence quantum efficiencies, etc.

5.
Chem Commun (Camb) ; 55(48): 6874-6877, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31125034

RESUMO

Here, we prepared the first series of 3D hybrid iodoplumbates with novel porous frameworks of [Pb8I21]5- directed by transition metal complex (TMC) cationic dyes of [TM(2.2-bipy)3]2+. The microporous materials exhibit outstanding visible light-driven photoelectric properties due to the effective photosensitization of the TMC dyes. The coexistence of stronger face- and weaker corner-shared connecting manners affords the feasibility of tailoring the 3D framework into low-dimensional skeletons, which provide a new structural prototype to modify the semiconducting properties similar to those of classic perovskites.

6.
Biomed Pharmacother ; 87: 263-273, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28063407

RESUMO

Photodynamic therapy (PDT) is entering the mainstream of the cancer treatments recently. Pyropheophorbide-a (Pa), as a degradation product of chlorophyll-a, has been shown to be a potent photosensitizer in photodynamic therapy. In this paper, we investigated the in vitro photodynamic therapy of 131-ortho-trifluoromethyl-phenylhydrazone modified pyropheophorbide-a (PHPa) against human HeLa cervical cancer cell line, together with ultraviolet-visible spectra, fluorescence emission spectra, stability in various solvents, and single oxygen quantum yield. The results indicated that PHPa not only showed a greater molar extinction coefficient reached 4.55×104 Lmol-1cm-1, the long absorption wavelength (681nm) as we expected that makes it potential in deep tumor treatment, but also showed better stability in near neutral phosphate buffers (pH 7.4) and culture medium, as well as higher single oxygen quantum yield (ФD=40.5%) in DMF solutions. Moreover, cell experiments suggested that PHPa could be uptaken by HeLa cells successfully, and has low dark toxicity without irradiation, but remarkable photo-cytotoxicity (IC50, 1.92±0.59µM) that the inhibition rate of HeLa cells could increase up 91.4% at 30µM of PHPa after irradiation. In addition, morphological changes of HeLa cells further demonstrated that PHPa can induce damage and apoptotic cell death. Furthermore, the mechanism of photochemical processes was investigated by using specific quenching agent sodium azide (SA) and D-mannitol (DM), respectively, which showed the formation of singlet oxygen (Type II reaction mechanism) may play a predominant role, Type I and Type II photodynamic reactions could occur simultaneously in this PHPa mediated PDT process.


Assuntos
Clorofila/análogos & derivados , Hidrazonas/síntese química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/síntese química , Porfirinas/síntese química , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Clorofila/síntese química , Clorofila/farmacologia , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Hidrazonas/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia
7.
Photochem Photobiol Sci ; 15(12): 1567-1578, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27872929

RESUMO

Magnetic iron oxide modified pyropheophorbide-a fluorescence nanoparticles, Fe3O4@SiO2@APTES@PPa (FSAP), were designed as magnetically targeted photodynamic antineoplastic agents and prepared through continuous covalent chemical modification on the surface of Fe3O4 nanoparticles. The properties of the intermediates and the final product were comprehensively characterized by transmission electron microscopy, powder X-ray diffraction analysis, Fourier transform infrared spectroscopy, vibrating sample magnetometry, zeta potential measurement, ultraviolet-visible absorption spectroscopy, fluorescence emission spectroscopy, and thermogravimetric analysis. In this work, we demonstrated the in vitro photodynamic therapy (PDT) of FSAP against ovarian cancer (SKOV-3) cells, which indicated that FSAP could be taken up successfully and showed low dark toxicity without irradiation, but remarkable phototoxicity after irradiation. Meanwhile, FSAP had showed good biocompatibility and low dark toxicity against normal cells in the biological experiments on mouse normal fibroblast cell lines (L929 cells). In addition, in the photochemical process of FSAP mediated photodynamic therapy, the Type-II photo-oxygenation process (generated singlet oxygen) played an important role in the induction of cell damage.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Compostos Férricos/química , Magnetismo , Nanopartículas/química , Fármacos Fotossensibilizantes/química , Animais , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Neoplasias Ovarianas , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Dióxido de Silício
8.
Molecules ; 21(5)2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27136527

RESUMO

Photodynamic therapy (PDT) has attracted widespread attention due to its potential in the treatment of various cancers. Porphyrinic pyropheophorbide-a (PPa) has been shown to be a potent photosensitizer in PDT experiments. In this paper, a C-3¹,13¹ bisphenylhydrazone modified methyl pyropheophorbide-a (BPHM) was designed and synthesized with the consideration that phenylhydrazone structure may extend absorption wavelength of methyl pyro-pheophorbide-a (Mppa), and make the photosensitizer potential in deep tumor treatment. The synthesis, spectral properties and in vitro photodynamic therapy (PDT) against human HeLa cervical cancer cell line was studied. Methyl thiazolyl tetrazolium (MTT) assay showed the title compound could achieve strong inhibition of cervical cancer cell viability under visible light (675 nm, 25 J/cm²). Cell uptake experiments were performed on HeLa cells. Morphological changes were examined and analyzed by fluorescent inverted microscope. In addition, the mechanism of the photochemical processes of PDT was investigated, which showed that the formation of singlet oxygen after treatment with PDT played a moderate important role.


Assuntos
Antineoplásicos/uso terapêutico , Hidrazonas/uso terapêutico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Antineoplásicos/química , Antineoplásicos/metabolismo , Células HeLa , Humanos , Hidrazonas/química , Manitol/farmacologia , Estrutura Molecular , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/metabolismo , Porfirinas/química , Espécies Reativas de Oxigênio/metabolismo , Azida Sódica/farmacologia
9.
Molecules ; 21(1): E107, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-26797591

RESUMO

The design and synthesis of selective and sensitive chemosensors for the quantification of environmentally and biologically important ionic species has attracted widespread attention. Amidochlorin p6 (ACP); an effective colorimetric and fluorescent probe for copper ions (Cu(2+)) in aqueous solution derived from methyl pheophorbide-a (MPa) was designed and synthesized. A remarkable color change from pale yellow to blue was easily observed by the naked eye upon addition of Cu(2+); and a fluorescence quenching was also determined. The research of fluorescent quenching of ACP-Cu(2+) complexation showed the detection limit was 7.5 × 10(-8) mol/L; which suggested that ACP can act as a high sensitive probe for Cu(2+) and can be used to quantitatively detect low levels of Cu(2+) in aqueous solution. In aqueous solution the probe exhibits excellent selectivity and sensitivity toward Cu(2+) ions over other metal ions (M = Zn(2+); Ni(2+); Ba(2+); Ag⁺; Co(2+); Na⁺; K⁺; Mg(2+); Cd(2+); Pb(2+); Mn(2+); Fe(3+); and Ca(2+)). The obvious change from pale yellow to blue upon the addition of Cu(2+) could make it a suitable "naked eye" indicator for Cu(2+).


Assuntos
Colorimetria/métodos , Cobre/análise , Corantes Fluorescentes , Íons/análise , Corantes Fluorescentes/química , Concentração de Íons de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Sensibilidade e Especificidade
10.
Sci Technol Adv Mater ; 14(2): 025004, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27877572

RESUMO

Magnetic and macro/mesoporous bioactive glasses were synthesized by a one-pot method via a handy salt leaching technique. It was identified to be an effective and simple synthetic strategy. The non-ionic triblock copolymer, poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (P123), was used as the structure directing agent for mesoporous structure but also as the reductant to reduce the iron source into magnetic iron oxide. The prepared materials exhibited excellent super-paramagnetic property with interconnected macroporous (200-300 µm) and mesoporous (3.4 nm) structure. Furthermore, their outstanding drug storage/release properties and rapid (5) induction of hydroxyapatite growth ability were investigated after immersing in simulated body fluid solution at 37 °C. Notably, the biocompatibility assessment confirmed that the materials obtained presented good biocompatibility and enhanced adherence of HeLa cells. Herein, the novel materials are expected to have potential application for bone tissue engineering.

11.
Org Lett ; 11(6): 1429-32, 2009 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-19231852

RESUMO

The synthesis of central-ring halogenated pentiptycene phenols 12-14 and dihalogenated pentiptycenes 15-17 is reported. Their utilities as building blocks for preparing new pentiptycene-derived pi-conjugated systems through the Sonogashira, Heck, and Suzuki reactions are also demonstrated.

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