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1.
Virus Res ; 286: 198068, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32565126

RESUMO

The emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to a renewed interest in studying the role of the spike S glycoprotein in regulating coronavirus infections in the natural host. Taking advantage of the cryo-electron microscopy structure of SARS-CoV-2 S trimer in the prefusion conformation, we performed a virtual screening simulation with the aim to identify novel molecules that could be used as fusion inhibitors. The spike glycoprotein structure has been completed using modeling techniques and its inner cavity, needful for the postfusion transition of the trimer, has been scanned for the identification of strongly interacting available drugs. Finally, the stability of the protein-drug top complexes has been tested using classical molecular dynamics simulations. The free energy of interaction of the molecules to the spike protein has been evaluated through the MM/GBSA method and per-residue decomposition analysis. Results have been critically discussed considering previous scientific knowledge concerning the selected compounds and sequence alignments have been carried out to evaluate the spike glycoprotein similarity among the betacoronavirus family members. Finally, a cocktail of drugs that may be used as SARS-CoV-2 fusion inhibitors has been suggested.


Assuntos
Antivirais/química , Betacoronavirus/química , Compostos Heterocíclicos de 4 ou mais Anéis/química , Indóis/química , Perileno/análogos & derivados , Glicoproteína da Espícula de Coronavírus/química , Sulfonamidas/química , Antivirais/farmacologia , Betacoronavirus/patogenicidade , Sítios de Ligação , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Expressão Gênica , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Ensaios de Triagem em Larga Escala , Humanos , Indóis/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Pandemias , Perileno/química , Perileno/farmacologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Sulfonamidas/farmacologia , Termodinâmica , Interface Usuário-Computador , Internalização do Vírus/efeitos dos fármacos
2.
Chemosphere ; 253: 126751, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32302913

RESUMO

A novel n-n type inorganic/organic heterojunction of flaky-like BiOCl/PDI photocatalyst was constructed by water bath heating method. Meanwhile, a simple method - secondary self-assembly was used to prepare the BiOCl/PDI with a special band structure. The photocatalytic activities were evaluated by degrading aqueous organic pollutants under visible light (λ > 420 nm). The removal rates of 5 mg L-1 phenol (non-ionic type), methyl orange (MO, anionic type), rhodamine B (RhB, cationic type) and 10 mg L-1 RhB by secondary self-assembly BiOCl/PDI (BiOCl/PDI-2) were 8.0%, 3.4%, 27.8% and 78.9% higher than self-assembly BiOCl/PDI (BiOCl/PDI-1) under visible light (λ > 420 nm). The better photocatalytic activity for BiOCl/PDI-2 was attributed to the optimization of energy-band structures, which arose from different exposed surfaces, narrower interplanar spacing and stronger visible light absorption performance. Under acidic condition, BiOCl/PDI-2 showed a good photocatalytic activity, which was not affected by neutral ionic intensity and had good recycling properties. Moreover, the photocatalytic mechanism was explored by free radical capture test and electron paramagnetic resonance (EPR), and contribution of active species was calculated. The main active species of BiOCl/PDI-2 were ·O2-, 1O2 and h+. Our work may provide a route to design efficient inorganic/organic heterojunctions for organic pollutants degradation.


Assuntos
Bismuto/química , Imidas/química , Luz , Nanoestruturas/química , Perileno/análogos & derivados , Poluentes Químicos da Água/análise , Compostos Azo/análise , Compostos Azo/efeitos da radiação , Catálise , Perileno/química , Fenóis/análise , Fenóis/efeitos da radiação , Rodaminas/análise , Rodaminas/efeitos da radiação , Propriedades de Superfície , Poluentes Químicos da Água/efeitos da radiação
3.
Mar Drugs ; 18(1)2020 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-31963874

RESUMO

Five new perylenequinone derivatives, altertoxins VIII-XII (1-5), as well as one known compound cladosporol I (6), were isolated from the fermentation broth of the marine-derived fungus Cladosporium sp. KFD33 from a blood cockle from Haikou Bay, China. Their structures were determined based on spectroscopic methods and ECD spectra analysis along with quantum ECD calculations. Compounds 1-6 exhibited quorum sensing inhibitory activities against Chromobacterium violaceum CV026 with MIC values of 30, 30, 20, 30, 20 and 30 µg/well, respectively.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Cladosporium/química , Perileno/análogos & derivados , Quinonas/química , Percepção de Quorum/efeitos dos fármacos , China , Testes de Sensibilidade Microbiana/métodos , Naftalenos/química , Naftalenos/farmacologia , Perileno/química , Perileno/farmacologia , Quinonas/farmacologia
4.
Chem Commun (Camb) ; 56(11): 1705-1708, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31942910

RESUMO

We report ultrathin organic photovoltaic elements optimized to run photofaradaic reactions in biological conditions. We demonstrate concurrent oxygen reduction to hydrogen peroxide and glucose oxidation. The devices are powered by deep-red irradiation in the tissue transparency window. We utilize bilayers of phthalocyanine, acting as the light absorber, and perylene diimide, functioning as both electron-acceptor and the hydrogen peroxide evolution electrocatalyst. These heterojunction bilayers are stable when irradiated in simulated physiological conditions, producing photovoltages sufficient to simultaneously drive cathodic oxygen reduction to H2O2 and anodic oxidation of glucose. We find that optimization of the anode metal is critical for sustained photofaradaic reactivity. Our results demonstrate a robust "wet" thin film photovoltaic with potential for physiological applications where localized electrochemical manipulation is desired, in particular the delivery of reactive oxygen species.


Assuntos
Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/síntese química , Imidas/química , Indóis/química , Perileno/análogos & derivados , Técnicas Eletroquímicas/instrumentação , Desenho de Equipamento , Glucose/química , Ouro/química , Imidas/efeitos da radiação , Indóis/efeitos da radiação , Luz , Membranas Artificiais , Oxirredução , Oxigênio/química , Perileno/química , Perileno/efeitos da radiação , Fotoquímica/métodos
5.
Chem Biodivers ; 17(1): e1900596, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31782894

RESUMO

Within Sicilian flora, the genus Hypericum (Guttiferae) includes 10 native species, the most popular of which is H. perforatum. Hypericum's most investigated active compounds belong to naphtodianthrones (hypericin, pseudohypericin) and phloroglucinols (hyperforin, adhyperforin), and the commercial value of the drug is graded according to its total hypericin content. Ethnobotanical sources attribute the therapeutic properties recognized for H. perforatum, also to other Hypericum species. However, their smaller distribution inside the territory suggests that an industrial use of such species, when collected from the wild, would result in an unacceptable depletion of their natural stands. This study investigated about the potential pharmacological properties of 48 accessions from six native species of Hypericum, including H. perforatum and five 'minor' species, also comparing, when possible, wild and cultivated sources. The variability in the content of active metabolites was remarkably high, and the differences within the species were often comparable to the differences among species. No difference was enlightened between wild and cultivated plants. A carefully planned cultivation of Hypericum seems the best option to achieve high and steady biomass yields, but there is a need for phytochemical studies, aimed to identify for multiplication the genotypes with the highest content of the active metabolites.


Assuntos
Hypericum/química , Perileno/análogos & derivados , Floroglucinol/análogos & derivados , Terpenos/química , Hypericum/metabolismo , Perileno/química , Perileno/metabolismo , Floroglucinol/química , Floroglucinol/metabolismo , Sicília , Especificidade da Espécie , Terpenos/metabolismo
6.
Chemistry ; 26(12): 2741-2748, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31886910

RESUMO

To achieve a highly efficient, dual-state emission platform for picric acid (PA) detection and latent fingerprint (LFP) visualization, flexible alkyl chains have been facilely attached to the commercial organic dye 3,4,9,10-perylenetetracarboxylic dianhydride to provide the target perylenetetracarboxylate molecules PTCA-C4, PTCA-C6, and PTCA-C12. Interestingly, all these molecules exhibited impressive fluorescence characteristics with high photoluminescence quantum yields (PLQYs) of around 93.0 % in dilute solution. Also, emissive features were observed in the solid state because close molecular packing is prevented by the alkyl chains, especially for PTCA-C6, which has a high PLQY value of 49.0 %. Benefiting from its impressive fluorescence performance in both solution and as aggregates, PTCA-C6 was used as a dual-state emission platform for PA detection and also LFP visualization. For example, double-responsive fluorescence quenching in solution was observed in PA detection studies, resulting in high quenching constants (KSV ) and also low limit-of-detection values. Furthermore, the fingerprint powder based on PTCA-C6 also presented an impressive performance on various substrates in terms of fluorescence intensity and resolution, clearly providing the specific fine details of latent fingerprints. These results demonstrate that the facilely synthesized PTCA-C6 with efficient dual-state emission exhibits great potential in the real-world applications of PA detection and LFP visualization.


Assuntos
Anidridos/química , Dermatoglifia , Corantes Fluorescentes/síntese química , Perileno/análogos & derivados , Picratos/análise , Teoria da Densidade Funcional , Humanos , Limite de Detecção , Estrutura Molecular , Perileno/química , Espectrometria de Fluorescência
7.
Mater Sci Eng C Mater Biol Appl ; 106: 110230, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753349

RESUMO

There is an urgent need for new antibacterial strategies to overcome the emergence of antibiotic resistance. Antibacterial photodynamic therapy (APDT) may be an effective method to deliver photosensitizers for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. Here, we report that the photosensitizer hypocrellin A (HA) loaded into lipase-sensitive methoxy poly (ethylene glycol)-block-poly(ε-caprolactone) (mPEG-PCL) micelles showed high anti-MRSA activity in vitro and in vivo by PDT. Once the micelles come into contact with bacteria that secrete lipase, the PCL is degraded to release HA. Our results showed that the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of mPEG-PCL/HA micelles after light irradiation were 0.69 and 1.38 mg/L (HA concentration), respectively. In the dark, the MIC and MBC of the micelles were 250 and 500 mg/L (HA concentration), respectively. The fluorescent stain results further demonstrated the photodynamic antibacterial activity of mPEG-PCL/HA micelles. The survival rate of mice subjected to experimental acute peritonitis increased to 86% after treated with the micelles. The polymeric micelles showed low hemolytic activity and biocompatibility, simultaneously preventing aggregation in vivo and enhancing the water solubility of HA. Thus, the photosensitizer HA loaded micelles could be used as APDT for infections caused by bacteria without antibiotic resistance.


Assuntos
Lipase/química , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Perileno/análogos & derivados , Polímeros/química , Quinonas/química , Quinonas/uso terapêutico , Animais , Antibacterianos/química , Antibacterianos/uso terapêutico , Portadores de Fármacos/química , Feminino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Micelas , Testes de Sensibilidade Microbiana , Perileno/química , Perileno/uso terapêutico , Fotoquimioterapia
8.
Molecules ; 24(23)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810324

RESUMO

Perylene diimide (PDI) is one of the most studied functional dyes due to their structural versatility and fine tuning of the materials properties. Core substituted PDIs are prominent n-type semiconductor materials that could be used as non-fullerene acceptors in organic photovoltaics. Herein, we develop versatile organic building blocks based on PDI by decorating the PDI core with quinoline groups. Styryl and hydroxy phenyl mono and difunctionalized molecules were prepared using mono-nitro and dibromo bay substituted PDIs by Suzuki coupling with the respective boronic acid derivatives. A novel methodology using nitro-PDI under Suzuki coupling conditions as an electrophile partner was successfully tested. Furthermore, the PDI derivatives were used for the synthesis of soluble, electron accepting small molecules combining PDI with weak electron withdrawing quinoline derivatives. The new molecules presented wide absorbance in the visible spectrum from 450 to almost 700 nm while their LUMO levels and their energy levels are in the range of -3.8 to -4.2 eV.


Assuntos
Imidas/química , Perileno/análogos & derivados , Quinolinas/química , Fenômenos Químicos , Técnicas de Química Sintética , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Perileno/química , Quinolinas/síntese química , Solubilidade
9.
Chem Commun (Camb) ; 55(96): 14446-14449, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31724658

RESUMO

A rational design of a benzoperylene probe BP-3 with positive charge allows for turn-on excimer emission, and wash-free cell membrane imaging. BP-3 possesses excellent chemical, thermal and photo stability. And the Stokes shift of the excimer emission is considerably large (90-100 nm), which very much avoids the background fluorescence interference.


Assuntos
Membrana Celular/química , Corantes Fluorescentes/química , Perileno/análogos & derivados , Humanos , Células MCF-7 , Microscopia Confocal , Perileno/química , Solventes , Espectrometria de Fluorescência
10.
ACS Appl Mater Interfaces ; 11(48): 44989-44998, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31755268

RESUMO

Tumor hypoxia severely limits the therapeutic efficacy of solid tumors in photodynamic therapy. One strategy is to develop photosensitizers with simultaneously high efficiency in photodynamic (PDT) and photothermal therapies (PTT) in a single natural-origin phototheranostic agent to overcome this problem. However, less attention has been paid to the natural-origin phototheranostic agent with high PDT and PTT efficiencies even though they have negligible side effects and are environmentally sustainable in comparison with many reported phototheranostic agents. In addition, almost all clinical applied photosensitizers are of natural origin so far. Herein, we synthesized a natural product-based hypocrellin derivative (AETHB), with a high singlet oxygen quantum yield of 0.64 as an efficient photosensitizer different from commercially available porphyrin-based photosensitizers. AETHB is further assembled with human serum albumin to construct nanoparticles (HSA-AETHB NPs) with a high photothermal conversion efficiency (more than 50%). As-prepared HSA-AETHB NPs have shown good water solubility and biocompatibility, pH and light stability, wide absorption (400-750 nm), and NIR emission centered at 710 nm. More importantly, HSA-AETHB NPs can be applied for fluorescent/photoacoustic dual-mode imaging and simultaneously highly efficient PDT/PTT in hypoxic solid tumors. Therefore, this natural-origin multifunctional phototheranostic agent is showing very promising for effective, precise, and safe cancer therapy in clinical applications.


Assuntos
Hipertermia Induzida , Neoplasias/terapia , Perileno/análogos & derivados , Fotoquimioterapia , Quinonas/química , Albumina Sérica/química , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Raios Infravermelhos , Camundongos , Camundongos Nus , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Perileno/administração & dosagem , Perileno/química , Quinonas/administração & dosagem , Nanomedicina Teranóstica
11.
Int J Mol Sci ; 20(20)2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31635234

RESUMO

In order to improve the poor film-forming ability of polymeric ladderphane, di-block copolymers containing perylene diimide (PDI)-linked double-stranded poly(1,6-heptadiyne) ladderphane and branched alkyl side chains modified single-stranded poly(1,6-heptadiyne) were synthesized by metathesis cyclopolymerization (MCP) using Grubbs third-generation catalyst (Ru-III) in tetrahydrofuran solvent. The first block containing the ladderphane structure leads to higher thermal-stability, wider UV-vis absorption, lower LUMO level and ladderphane-induced rigidity and poor film-forming ability. The second block containing long alkyl chains is crucial for the guarantee of excellent film-forming ability. By comparing the effect of ladderphane structure on the resulted copolymers, single-stranded poly(1,6-heptadiyne) derivatives with PDI pedant were also processed. The structures of copolymers were proved by 1H NMR and gel permeation chromatography, electrochemical, photophysical, and thermal-stability performance were achieved by cyclic voltammetry (CV), UV-visible spectroscopy and thermogravimetric analysis (TGA) measurements. According to the experiment results, both copolymers possessed outstanding film-forming ability, which cannot be realized by small PDI molecules and oligomers. And they can serve as a superior candidate as for n-type materials, especially for their relatively wide range of light absorption (λ = 200~800 nm), and lower LUMO level (-4.3 and -4.0 eV).


Assuntos
Imidas/química , Perileno/análogos & derivados , Polímeros/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Perileno/química , Polimerização , Análise Espectral , Termogravimetria
12.
Nanoscale ; 11(43): 20910-20916, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31660563

RESUMO

In the cathodic electrochemiluminescence (ECL) field, most reported luminophores produced ECL emission at high potentials (more than -1.3 V vs. Ag/AgCl), which was adverse for both fundamental studies and practical application. It was important to screen novel ECL luminophores and coreactants for the development of ECL. In this work, N,N'-dimethyl-3,4,9,10-perylenedicarboximide (PDI-CH3) is reported to produce ECL at -0.47 V using K2S2O8 as a coreactant in an aqueous system. In addition, the ECL wavelength was 689 nm, which was interpreted with the emission of excited PDI-CH3 dimers. Finally, this low-triggering-potential ECL system was used to construct sandwiched immunosensors to detect carcinoembryonic antigen (CEA) with the potential range from 0 to -0.8 V. In this immunosensor, PDI-CH3 and gold nanoparticles (AuNPs) reduced by citrate were grafted onto graphite oxide (GO) to label secondary antibodies (Ab2). This immunosensor could sensitively detect CEA with the linear response range between 1 fg mL-1 and 1 µg mL-1 and detection limit 0.29 fg mL-1. In addition, this immunosensor showed good feasibility in various cancer serum samples.


Assuntos
Corantes Fluorescentes/química , Imidas/química , Imunoensaio/métodos , Perileno/análogos & derivados , Anticorpos/imunologia , Antígeno Carcinoembrionário/análise , Antígeno Carcinoembrionário/imunologia , Técnicas Eletroquímicas , Eletrodos , Ouro/química , Grafite/química , Limite de Detecção , Medições Luminescentes , Nanopartículas Metálicas/química , Perileno/química
13.
Analyst ; 144(21): 6193-6196, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31577279

RESUMO

We here describe a photocurrent generation system exploiting gold nanoparticles (AuNPs) that cover perylenediimide-DNA complexes on electrode surfaces. Enhanced photocurrents were generated by the irradiation of the AuNPs, attributed to the efficient excitation of the perylenediimides by a local electric field on the surface of the AuNPs.


Assuntos
DNA/química , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Fotoquímica/métodos , Técnicas Eletroquímicas/instrumentação , Eletrodos , Ouro/química , Ouro/efeitos da radiação , Imidas/química , Imidas/efeitos da radiação , Luz , Nanopartículas Metálicas/efeitos da radiação , Perileno/análogos & derivados , Perileno/química , Perileno/efeitos da radiação
14.
Chemistry ; 25(66): 15062-15066, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31553484

RESUMO

The aldol reaction is one of the most fundamental stereocontrolled carbon-carbon bond-forming reactions and is mainly catalyzed by aldolases in nature. Despite the fact that the aldol reaction has been widely proposed to be involved in fungal secondary metabolite biosynthesis, a dedicated aldolase that catalyzes stereoselective aldol reactions has only rarely been reported in fungi. Herein, we activated a cryptic polyketide biosynthetic gene cluster that was upregulated in the fungal wheat pathogen Parastagonospora nodorum during plant infection; this resulted in the production of the phytotoxic stemphyloxin II (1). Through heterologous reconstruction of the biosynthetic pathway and in vitro assay by using cell-free lysate from Aspergillus nidulans, we demonstrated that a berberine bridge enzyme (BBE)-like protein SthB catalyzes an intramolecular aldol reaction to establish the bridged tricyclo[6.2.2.02,7 ]dodecane skeleton in the post-assembly tailoring step. The characterization of SthB as an aldolase enriches the catalytic toolbox of classic reactions and the functional diversities of the BBE superfamily of enzymes.


Assuntos
Alcanos/química , Berberina/química , Frutose-Bifosfato Aldolase/metabolismo , Perileno/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Aspergillus nidulans/metabolismo , Biocatálise , Frutose-Bifosfato Aldolase/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Conformação Molecular , Família Multigênica , Perileno/análogos & derivados , Perileno/química , Estereoisomerismo
15.
Mater Sci Eng C Mater Biol Appl ; 105: 110052, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546360

RESUMO

Novel duck reovirus (NDRV) disease is a serious infectious disease for poultry, for which no effective therapy has been established. Therefore, development of novel antivirals against NDRV is urgently needed. In present study, we developed a complex wherein hypericin (HY), which shows broad-spectrum antiviral activity, was loaded onto graphene oxide (GO), which has a high drug-loading capacity and low cytotoxicity. The antiviral activity of the complex (GO/HY) was studied in DF-1 cells and in ducklings infected with the NDRV TH11 strain. GO/HY showed a dose-dependent inhibition of NDRV replication, which may be attributed to direct virus inactivation or inhibition of virus attachment. Western blotting and indirect immunofluorescence assay (IFA) showed markedly suppressed protein expression in GO/HY-treated NDRV-infected DF-1 cells. Moreover, GO/HY prolonged the survival time of the ducklings by reducing pathological lesions caused by the infection and inhibiting viral replication in the liver and lungs. These results suggest that GO/HY has antiviral activity against NDRV both in vitro and in vivo.


Assuntos
Portadores de Fármacos , Patos , Grafite , Orthoreovirus Aviário/metabolismo , Perileno/análogos & derivados , Doenças das Aves Domésticas , Infecções por Reoviridae , Animais , Linhagem Celular , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Patos/metabolismo , Patos/virologia , Grafite/química , Grafite/farmacologia , Perileno/química , Perileno/farmacologia , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/patologia , Doenças das Aves Domésticas/virologia , Infecções por Reoviridae/tratamento farmacológico , Infecções por Reoviridae/metabolismo , Infecções por Reoviridae/patologia , Infecções por Reoviridae/veterinária
16.
Biosens Bioelectron ; 145: 111702, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31561096

RESUMO

Photoelectrochemical (PEC) assay with low background, simple instrumentation and high sensitivity has deemed as one of the most potential strategies to simultaneous multi-component detection. How to distinguish photocurrent changes caused by various targets on a single sensing platform thus becomes the key issue to be resolved. Herein, we innovatively proposed a multiplex PEC biosensor based on wavelength distinguishable signal quenching and enhancing toward photoactive material 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) for simultaneous assay of dual metal ions. Briefly, S1 and S2 ssDNA containing sensitizer methylene blue and quencher ferrocene (termed as MB-S1 and Fc-S2), respectively, were first generated through target Pb2+ and Mg2+-induced DNAzyme-assisted target recycling, which thereafter were modified on PTCDA sensing platform specifically via host-guest recognition with ß-cyclodextrin (ß-CD). Interestingly, the sensitizer MB could enhance photocurrent of PTCDA under the excitation wavelength of 623 nm and 590 nm, respectively, while the quencher Fc just quencher the photocurrent of PTCDA under the excitation wavelength of 590 nm, thereby achieving wavelength distinguishable signal quenching and enhancing toward photoactive material PTCDA for simultaneous assay of dual metal ions. As a result, the conceived biosensor for Mg2+ and Pb2+ detection realized high sensitivity with detection limit of 0.3 pM and 0.3 nM, respectively. The proposed strategy not only for the first time achieved the discrimination of varied PEC signal caused by two targets with usage of sole photoelectric material, but also realized the simultaneous multiplex assay on a single sensing platform, providing a new way for constructing effective and sensitive PEC biosensor for multi-component detection.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Chumbo/isolamento & purificação , Magnésio/isolamento & purificação , Anidridos/química , Compostos Ferrosos/química , Ouro/química , Chumbo/química , Magnésio/química , Metalocenos/química , Azul de Metileno/química , Nanoestruturas/química , Perileno/análogos & derivados , Perileno/química
17.
Molecules ; 24(17)2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31470637

RESUMO

Metastatic melanoma (MM) has a poor prognosis and is attributed to late diagnoses only when metastases has already occurred. Thus, early diagnosis is crucial to improve its overall treatment efficacy. The standard diagnostic tools for MM are incisional biopsies and/or fine needle aspiration biopsies, while standard treatments involve surgery, chemotherapy, or irradiation therapy. The combination of photodynamic diagnosis (PDD) and therapy (PDT) utilizes a photosensitizer (PS) that, when excited by light of a low wavelength, can be used for fluorescent non-destructive diagnosis. However, when the same PS is activated at a higher wavelength of light, it can be cytotoxic and induce tumor destruction. This paper focuses on PS drugs that have been used for PDD as well as PDT treatment of MM. Furthermore, it emphasizes the need for continued investigation into enhanced PS delivery via active biomarkers and passive nanoparticle systems. This should improve PS drug absorption in MM cells and increase effectiveness of combinative photodynamic methods for the enhanced diagnosis and treatment of MM can become a reality.


Assuntos
Melanoma/diagnóstico por imagem , Melanoma/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/tratamento farmacológico , Ácido Aminolevulínico/química , Ácido Aminolevulínico/farmacocinética , Ácido Aminolevulínico/uso terapêutico , Biópsia por Agulha Fina , Portadores de Fármacos/síntese química , Diagnóstico Precoce , Humanos , Indóis/química , Indóis/farmacocinética , Indóis/uso terapêutico , Luz , Metástase Linfática , Melanoma/patologia , Imagem Molecular/métodos , Nanopartículas/administração & dosagem , Nanopartículas/química , Perileno/análogos & derivados , Perileno/química , Perileno/farmacocinética , Perileno/uso terapêutico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacocinética , Neoplasias Cutâneas/patologia
18.
Int J Pharm ; 570: 118666, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31494239

RESUMO

The naturally occurring anthraquinone derivative hypericin is a highly potent photosensitiser. Several in vitro studies show high phototoxicity of the pigment towards gram-positive bacteria. Nevertheless, the highly lipophilic nature and poor bioavailability prevent its application in daily clinical practice thus leading to a limited therapeutic value of hypericin. Liposomal encapsulation could help overcome these limitations and would make hypericin available for daily clinical practice. The use of liposomes as carriers for hypericin in antimicrobial photodynamic therapy (aPDT) is quite new. The aim of this work was to improve the photodynamic efficiency of the previously mentioned carriers by entrapping hypericin in the aqueous compartment of the liposomes. Therefore, a water-soluble inclusion complex of hypericin and (2-hydroxypropyl)-beta-cyclodextrin (Hyp-HPßCD) was prepared. After encapsulation of the inclusion complex into DSPC and DSPC/DPPC/DSPE-PEG liposomes with the dehydration-rehydration vesicle (DRV) method, the formulations were physicochemical characterised. The photodynamic efficiency towards the gram-positive model strain Staphylococcus saprophyticus subsp. bovis. was tested on planktonic cells as well as on biofilms. DSPC liposomes achieved a 4.1log reduction and the DSPC/DPPC/DSPE-PEG liposomes a 2.6log reduction in growth of planktonic bacteria, while Hyp-HPßCD showed total eradication. Even bacterial cells growing in a biofilm could be treated effectively in vitro.


Assuntos
Antibacterianos/química , Lipossomos/química , Perileno/análogos & derivados , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Composição de Medicamentos/métodos , Perileno/química , Fosfatidiletanolaminas/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Polietilenoglicóis/química , Staphylococcus saprophyticus/efeitos dos fármacos , beta-Ciclodextrinas/química
19.
Mikrochim Acta ; 186(10): 677, 2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511998

RESUMO

A Pb(II)-DNAzyme is used in an amperometric method for the determination of Pb(II). The method is based on two feedback processes. In the first, the Pb(II)-DNAzyme initiates a reaction in presence of Pb(II) in a micro-tube to release a linear DNA (S1). In the second, the S1 triggers the recycling amplification between two types of hairpin-shaped DNA templates (H1 and H2) which consist of a primer sequence and a Pb(II)-DNAzyme substrate sequence. The Pb(II)-DNAzyme has excellent cleavage specificity toward the substrate sequence in S1 that combined firstly with H1 and then is linked to H2. This process will connect H1 and H2. After hybridization with H1 and H2 to form two DNA complexes, S1 is released and initiates the next recycling process. This results in efficient amplification. A glassy carbon electrode (GCE) was immersed into solution of HAuCl4 to electrodeposit a layer of gold nanoparticles. This is followed by the assembly of the hairpin probe H1 on the GCE. In addition, a nanohybrid consisting of 3, 4, 9, 10-Perylenetetracarboxylic acid (PTCA) and nitrogen-doped graphene (NG) was loaded with electroactive thionine (Thi) and gold to form nanoparticles of type NG-PTCA-Thi-Au. This is responsible for generating the amperometric signal (best measured at around -0.30 V vs. SCE) and also acts as the reducing agent for synthesizing the NG-PTCA-Thi-Au nanohybrid. H2 is immobilized on NG-PTCA-Thi-Au to form a new tracer label. The concentration of Pb(II) in a solution can be quantified by determination of the amount of cleaved S1. The method has high sensitivity and selectivity for Pb(II). The detection limit is 0.42 pM (S/N = 3), and the detection range extends from 1 pM to 1000 nM. Graphical abstract Schematic representation of electrodes for the determination of the lead ions (Pb2+). The sensor is using Pb2+-DNAzyme assisted recycling amplification based on hairpin assembly on a composite prepared from nitrogen doped graphene, perylenetetracarboxylic anhydride, thionine and gold nanoparticles (NG-PTCA-Thi-Au). This versatile platform expands studies on the detection of heavy metal ions.


Assuntos
DNA Catalítico/química , Técnicas Eletroquímicas , Chumbo/análise , Nanocompostos/química , Técnicas de Amplificação de Ácido Nucleico , Técnicas Biossensoriais , Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Nitrogênio/química , Hibridização de Ácido Nucleico , Perileno/química , Fenotiazinas/química
20.
Photodiagnosis Photodyn Ther ; 28: 38-52, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31430575

RESUMO

Hypericin (Hyp) is a naturally occurring compound used as photosensitizer in photodynamic therapy and diagnosis. Recently, we have shown that Hyp presence alone, without illumination, resulted in substantial biological effects at several sub-cellular levels. Hyp induced changes in cellular ultrastructure, mitochondria function and metabolism, and distribution of Bcl2 proteins in malignant and non-malignant cells. The molecular mechanisms that underlie Hyp light-independent effects are still elusive. We have hypothesized that Bcl2-Hyp interactions might be one possible mechanism. We performed molecular docking studies to determine the Hyp-Bcl2 interaction profile. Based on the interaction profiles small Bcl2 peptide segments were selected for further study. We designed small peptides corresponding to Bcl2 BH3 and BH1 domains and tested the binding of Hyp and Bcl2 known inhibitor, ABT263, to the peptides in computer modeling and in vitro binding studies. We employed endogenous tryptophan and tyrosine in the BH3 and BH1 peptides, respectively, and their fluorescent properties to show interaction with Hyp and ABT263. Overall, our results indicate that Hyp can interact with Bcl2 protein at its BH3-BH1 hydrophobic groove, and this interaction may trigger changes in intracellular distribution of Bcl2 proteins. In addition, our computer modeling results suggest that Hyp also interacts with other anti-apoptotic members of Bcl2 family similar to the known BH3 mimetics. Our findings are novel and might contribute to understanding Hyp light-independent effects. In addition, they may substantiate the therapeutic use of Hyp as a BH3 mimetic molecule to enhance other cancer treatments.


Assuntos
Glioma/tratamento farmacológico , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Compostos de Anilina/química , Compostos de Anilina/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fluorescência , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Perileno/química , Perileno/farmacologia , Fármacos Fotossensibilizantes/química , Sulfonamidas/química , Sulfonamidas/farmacologia , Triptofano/farmacologia , Tirosina/farmacologia
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