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1.
Phys Chem Chem Phys ; 21(31): 17163-17169, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31342023

RESUMO

Two-dimensional (2D) heteromaterials with large interface contact and intimate interfacial charge transition have been considered to be an ideal model for constructing highly efficient photocatalysts. However, few studies have reported on these 2D heterojunctions. Herein, we report a series of new 2D heterojunctions comprising polyimide (PI) and perylene-3,4,9,10-tetracarboxylic dianhydride (TD). These heterojunctions, denoted as PI-TDx (where x represents the amount of TD added, i.e., x = 0.13, 0.18, 0.27, 0.54, and 1.08 g), were prepared by the solid thermal copolymerization of melamine (MA), pyromellitic dianhydride (PD), and different amounts of TD. FT-IR spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy analyses were used to verify the 2D heterojunction structure. Photocatalytic experiments reveal that PI-TDx exhibit excellent and stable photocatalytic performance for the degradation of the organic dyes rhodamine B (RhB) and methyl violet (MV), as well as for the photoreduction of Cr(vi), under visible-light irradiation. Among the samples, PI-TD0.18 exhibits the best photocatalytic performance. Its activity is about 2.7 times and 7.5 times higher than that of individual PIMP (formed by MA and PD) and PIMT (formed by MA and TD) for RhB degradation, respectively. Notably, PI-TD0.18 retains a certain photocatalytic activity under light irradiation at 600 nm. The photocatalytic-mechanism study demonstrates that PI-TD0.18 has a classic type-II heterojunction. Its 2D heterojunction greatly enhances the visible-light absorption of the composites and effectively suppresses the radiation recombination of photogenerated carriers, thereby improving its charge transfer and separation abilities and providing excellent photocatalytic performance. This work may serve as an important reference for the design and construction of new highly efficient 2D organic conjugated-polymer photocatalysts.


Assuntos
Poluentes Ambientais/química , Perileno/análogos & derivados , Perileno/química , Resinas Sintéticas/química , Catálise , Cromo/química , Corantes/química , Violeta Genciana/química , Luz , Oxirredução , Processos Fotoquímicos , Rodaminas/química , Propriedades de Superfície
2.
Photochem Photobiol Sci ; 18(8): 2023-2030, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31290525

RESUMO

Rising demands for renewable energy sources have led to the development of dye sensitized solar cells. It is a challenge to find a good and low cost sensitizer, which has a low environmental impact. In this work, we conducted spectroscopic and electrochemical experiments, as well as quantum-chemical calculations of the natural pigment hypericin, in order to provide insight into its sensitizing efficiency. To this end, three identical cells were made and characterized. Although this pigment exhibited good adsorption onto a semiconductor surface, a high molar absorption coefficient (43 700 L mol-1 cm-1) and favorable alignment of energy levels and provided a long lifetime of electrons (17.8 ms) in the TiO2 photoanode, it was found that the efficiency of hypericin-sensitized solar cells was very low, only 0.0245%. We suggest that this inefficiency originated from a low injection of electrons into the conduction band of TiO2. This conclusion is supported by the density functional theory calculations which revealed a low electron density in the anchoring groups of electronically excited hypericin. The results of this work could be valuable not only in the photovoltaic aspect, but also for application of hypericin in medicine in photodynamic therapy.


Assuntos
Corantes/química , Fontes de Energia Elétrica , Elétrons , Perileno/análogos & derivados , Energia Solar , Teoria da Densidade Funcional , Perileno/química , Titânio/química
3.
Chemistry ; 25(52): 12137-12144, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31276238

RESUMO

Isomerism heavily influences the optoelectronic properties and self-assembly behavior of compounds and subsequently affects their device performance. Herein, two pairs of isomeric perylene diimide (PDI) dimers, PDI and PDI2, were designed and synthesized. The electron-deficient 9,10-anthraquinone group was employed as the bridge, and thus, the resultant dimers exhibited an acceptor-acceptor-acceptor (A-A-A) structure. To determine the isomeric effects on the optoelectronic properties and photovoltaic performance of these dimers, their absorptivity, luminescence, and redox behavior were studied. Bulk heterojunction organic solar cells based on these four dimers were fabricated and measured. The two PDI dimers exhibited clear differences in photovoltaic performance, whereas the two PDI2 analogues showed similar power conversion efficiencies (PCEs). The PCEs of the two PDI2 dimers are much higher than those of the PDI dimers. These results illustrate that the isomeric effect of PDI dimers is much larger than that of PDI2 dimers on the device performance, and proper expansion of conjugation could improve the device performance.


Assuntos
Antraquinonas/química , Imidas/química , Perileno/análogos & derivados , Dimerização , Eletrônica , Isomerismo , Oxirredução , Perileno/química , Energia Solar
5.
Appl Spectrosc ; 73(8): 936-944, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31149836

RESUMO

Hypericin (Hyp) is a natural compound with interesting photophysical and pharmacological properties, which has been used in photodynamic therapy and photodynamic inactivation of microorganisms. Its synthesis is based on a series of chemical processes that ends with a light-drug interaction by the photoconversion of protohypericin (pHyp) to Hyp. Although this photosensitizer is used in a variety of medical applications, the photophysical and photochemical mechanisms involved in the final step related to the photo production of Hyp are not completely understood at the molecular level. Protohypericin concentration, solvents, light irradiation under different wavelengths, and a sort of variables could play an important role in predicting the yielding of this photoconversion process. Here, we used the high-sensitive and remote measurement characteristics of the time-resolved thermal lens technique to investigate the relation between the light-induced photoconversion rate of pHyp to Hyp and the initial concentration pHyp. The results show a linear dependence of the photoreaction rate with the concentration of pHyp, indicating that the overall reaction process includes steps comprising the formation of distinct intermediate species. We demonstrate the applicability of the thermal lens technique for the photochemical characterization of photosensitive drugs at low concentration levels.


Assuntos
Perileno/análogos & derivados , Fármacos Fotossensibilizantes/síntese química , Lentes , Perileno/síntese química , Perileno/química , Fotoquimioterapia
6.
Adv Mater ; 31(33): e1901965, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31237375

RESUMO

Antibacterial photocatalytic therapy has been reported as a promising alternative water disinfection technology for combating antibiotic-resistant bacteria. Numerous inorganic nanosystems have been developed as antibiotic replacements for bacterial infection treatment, but these are limited due to the toxicity risk of heavy metal species. Organic semiconductor photocatalytic materials have attracted great attention due to their good biocompatibility, chemically tunable electronic structure, diverse structural flexibility, suitable band gap, low cost, and the abundance of the resources they require. An all-organic composite photocatalytic nanomaterial C3 N4 /perylene-3,4,9,10-tetracarboxylic diimide (PDINH) heterostructure is created through recrystallization of PDINH on the surface of C3 N4 in situ, resulting in enhanced photocatalytic efficiency due to the formation of a basal heterostructure. The absorption spectrum of this composite structure can be extended from ultraviolet to near-infrared light (750 nm), enhancing the photocatalytic effect to produce more reactive oxygen species, which have an excellent inactivation effect on both Gram-negative and positive bacteria, while demonstrating negligible toxicity to normal tissue cells. An efficient promotion of infectious wound regeneration in mice with Staphylococcus aureus infected dermal wounds is demonstrated. This all-organic heterostructure shows great promise for use in wound disinfection.


Assuntos
Antibacterianos/química , Imidas/química , Nitrilos/química , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Semicondutores , Animais , Antibacterianos/uso terapêutico , Antibacterianos/toxicidade , Catálise , Sobrevivência Celular , Escherichia coli/efeitos dos fármacos , Feminino , Luz , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Nanoestruturas/química , Nitrilos/uso terapêutico , Nitrilos/toxicidade , Perileno/química , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/toxicidade , Porfirinas/uso terapêutico , Porfirinas/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Cicatrização , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia
7.
Chemistry ; 25(42): 9834-9839, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31173417

RESUMO

Introduction of chirality into a supramolecular self-assembly system plays an indispensable role in attaining specific molecular recognition ability. Herein, a chiral anticancer drug 5'-deoxy-5-fluorouridine (5'DFU) was explored for inducing the self-assembly of a cationic perylene diimide derivative containing boronic acid groups (PDI-PBA) into a highly ordered right-handed helical structure. As a result, PDI-PBA exhibited a molecular recognition ability towards 5'DFU among other cis-diols and anticancer drugs. With the help of a dynamic covalent bond and favorable hydrogen-bonding interactions, chirality transfer from chiral 5'DFU to achiral PDI-PBA breaks down the strong π-π stacking of PDI-PBA and makes it reorganize into highly ordered helical supramolecular structures. This work provides an insight into chiral anticancer drug tuning interactions of π-chromophores and the inducement of hierarchical self-assembly to achieve specific molecular recognition.


Assuntos
Antineoplásicos/química , Corantes Fluorescentes/química , Imidas/química , Perileno/análogos & derivados , Ácidos Borônicos/química , Ligações de Hidrogênio , Modelos Moleculares , Conformação Molecular , Perileno/química , Espectrometria de Fluorescência , Estereoisomerismo , Termodinâmica
8.
Bioelectrochemistry ; 129: 189-198, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31195330

RESUMO

A facile approach was reported to synthesize ß-cyclodextrin functionalized graphene that is bridged by 3,4,9,10-perylene tetracarboxylic acid (rGO-PTCA-CD) via a chemical route that involves the functionalization of rGO with PTCA followed by covalently cross-linking NH2-ß-CD. The as-prepared rGO-PTCA-CD was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy and electrochemical methods. The working electrodes were thoroughly studied for the cyclic voltammetry by using [Fe(CN)6]4-/3- as redox probe and using ferrocene as an internal standard. Furthermore, rGO-PTCA-CD was successfully applied to the recognition of phenylalanine enantiomers. The host-guest inclusion interaction between rGO-PTCA-CD and the phenylalanine enantiomers was investigated by differential pulse voltammetry with Fc used as a competitor. The recognition result showed that the rGO-PTCA-CD-modified glassy carbon electrode exhibited higher chiral recognition capability for L-Phe than for D-Phe with an enantioselectivity coefficient of 2.07. The proposed modified electrode had a limit of detection of 0.08 nM and 0.2 nM (S/N = 3) for L-Phe and D-Phe, respectively, with a linear response range of 0.01 mM to 5 mM, which was ascribed to the synergy of the rGO-PTCA (e.g., its excellent electrochemical performance) and ß-CD (e.g., the hydrophobic inner cavity with good molecular recognition and enrichment abilities).


Assuntos
Técnicas Eletroquímicas/métodos , Grafite/química , Perileno/química , Fenilalanina/análise , beta-Ciclodextrinas/química , Eletrodos , Limite de Detecção , Estereoisomerismo
9.
ACS Appl Mater Interfaces ; 11(18): 17079-17089, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30978000

RESUMO

Perylene bisimide derivatives show peculiar physical chemical features, such as a highly conjugated system, high extinction coefficients and elevated fluorescence quantum yields, making them suitable for the development of optical sensors of compounds of interest. In particular, they are characterized by the tendency to aggregate into π-π stacked supramolecular structures. In this contribution, the behavior of the PBI derivative N, N'-bis(2-(trimethylammonium)ethylene)perylene bisimide dichloride was investigated both in aqueous solution and on solid support. The electronic communication between PBI aggregates and biogenic amines was exploited in order to discriminate aromatic amines down to subnanomolar concentrations by observing PBI fluorescence variations in the presence of various amines and at different concentrations. The experimental findings were corroborated by density functional theory calculations. In particular, phenylethylamine and tyramine were demonstrated to be selectively detected down to 10-10 M concentration. Then, in order to develop a surface plasmon resonance (SPR) device, PBI was deposited onto a SPR support by means of the layer-by-layer method. PBI was deposited in the aggregated form and was demonstrated to preserve the capability to discriminate, selectively and with an outstanding analytical sensitivity, tyramine in the vapor phase and even if mixed with other aromatic amines.


Assuntos
Aminas Biogênicas/isolamento & purificação , Técnicas Biossensoriais , Fenetilaminas/isolamento & purificação , Tiramina/isolamento & purificação , Aminas Biogênicas/química , Corantes/química , Fluorescência , Imidas/química , Perileno/análogos & derivados , Perileno/química , Fenetilaminas/química , Pontos Quânticos/química , Soluções/química , Ressonância de Plasmônio de Superfície , Tiramina/química , Água/química
10.
ACS Appl Mater Interfaces ; 11(18): 16958-16964, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30993969

RESUMO

Photoelectrochemical (PEC) sensing techniques have attracted considerable concerns because of the intrinsic merit of complete separation between the excitation light and responsive current but still remain a great challenge for further potential application. It is assigned to the scarcity of photoactive materials with narrow band gap, good biosafety, and high photon-to-electron conversion efficiency and unfavorable processing methods for photoactive materials on indium tin oxide. Herein, we employed a perylene-based polymer (PTC-NH2) with exceptional photoelectrical properties to develop a red-light-driven PEC sensor for ultrasensitive biosensing based on its superior electrostatic intercalation efficiency in double-stranded DNA to that in single-stranded DNA, with DNA adenine methyltransferase (Dam MTase) as the model target. The prepared PTC-NH2 was characterized by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, and PEC techniques, and the results demonstrated that PTC-NH2 rather than metal oxides/metal sulfides/C3N4/metal complexes enjoyed the prominent capacity of converting light to current. Benefiting from the unique PEC properties of PTC-NH2 and target-initiated hybridization chain reaction (HCR) signal amplification, ultrasensitive detection of Dam MTase was accessibly realized with the detection limit of 0.015 U/mL, which is lower than that of PEC, electrochemical, or fluorescent biosensors previously reported. Furthermore, the proposed PEC sensor has been also applied in screening Dam MTase activity inhibitors. Therefore, the perylene-based PEC sensor exhibits great potential in early accurate diagnosis of DNA methylation-related diseases.


Assuntos
Técnicas Biossensoriais , DNA/química , Substâncias Intercalantes/química , DNA Metiltransferases Sítio Específica (Adenina-Específica)/isolamento & purificação , DNA de Cadeia Simples/efeitos da radiação , Técnicas Eletroquímicas/métodos , Humanos , Luz , Perileno/química , DNA Metiltransferases Sítio Específica (Adenina-Específica)/química , Compostos de Estanho/química
11.
Spectrochim Acta A Mol Biomol Spectrosc ; 218: 206-212, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30995578

RESUMO

Hydrogen sulfide (H2S) is a kind of gaseous signal molecule in many physiological processes. In order to detect H2S, a novel "turn on" fluorescent probe 6,12-dihydroxyperylene-1,7-dione (DPD) was designed and synthesized. The probe DPD is fluorescence silence, while the addition of H2S induces an obvious green fluorescence with an obvious color change from dark blue to yellow-green. The probe shows excellent selectivity, fast response (2.5min) and linear curve (0-90µM) in wide effective pH range (4-10). Competition experiments are also revealed in corresponding studies and the detection limit is 3.6µM. The response mechanism is proved to be the reduction of the probe by H2S, which is confirmed by 1H NMR. Furthermore, through the fluorescence turn-on signal toward H2S in Hela cells, probe DPD was successfully applied to monitor H2S in living Hela cells.


Assuntos
Corantes Fluorescentes/química , Sulfeto de Hidrogênio/análise , Perileno/análogos & derivados , Quinonas/química , Fluorescência , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Limite de Detecção , Microscopia Confocal , Imagem Óptica , Perileno/síntese química , Perileno/química , Quinonas/síntese química , Espectrometria de Fluorescência
12.
Chem Commun (Camb) ; 55(25): 3658-3661, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30855054

RESUMO

Due to the host-guest interaction between cucurbit[10]uril and perylenebisdiimide (PDI) derivatives, DNA-PDI conjugates can achieve morphological shifting from spherical micelles to two-dimensional nanosheets. The competitive binding between the guest 3,5-dimethyl-1-adamantanamine hydrochloride and PDI units induces the reversibility. The 2D nanosheets can act as addressable templates to organize the functional molecules through DNA hybridization.


Assuntos
DNA/química , Imidas/química , Difusão Dinâmica da Luz , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Perileno/química , Espectrometria de Fluorescência
13.
Chem Commun (Camb) ; 55(30): 4395-4398, 2019 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-30916082

RESUMO

A perylene probe PC4 is exploited as a membrane intercalating conjugated oligoelectrolyte for efficient antimicrobial photodynamic therapy. PC4 can also serve as a fluorescent microbial cell death marker.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Membranas Artificiais , Perileno/química , Perileno/farmacologia , Fotoquimioterapia , Polieletrólitos/química , Células A549 , Sobrevivência Celular/efeitos dos fármacos , Humanos
14.
Molecules ; 24(6)2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30897753

RESUMO

The Naoxinqing (NXQ) tablet is a standardised proprietary herbal product containing an extract of persimmon leaves (Diospyros kaki) for the management of cardio- and cerebrovascular diseases. Although previous reports suggested that the efficacy of NXQ is at least partly mediated by its anti-oxidative property, the anti-oxidative effect of the major components of NXQ has not been studied systematically. For quality control purposes, only analytical methods limited to 3 marker analytes have been reported, the extent to which the other components affect efficacy has not been explored. In this study, we developed an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC MS/MS) method for the identification of seven analytes (kaempferol-3-O-glucoside (astragalin), quercetin-3-O-galactoside (hypericin), quercetin-3-O-glucoside (isoquercitin), kaempferol, 3,4-dihydroxybenzoic acid (protocatechuic acid), and furan-2-carboxylic acid (pyromucic acid) and quercetin) in the NXQ. This is the first method reported and validated for the quantification of the seven major secondary metabolites in NXQ. The results for the quantified analytes were then compared in 15 different batches of NXQ. The variation observed in the seven components highlights the need to quantify key bioactive components to ensure product consistency. Radical scavenging activity and abundance was used to rank the analytes. The anti-oxidative effects of NXQ were examined using cultured human vascular endothelial cells (EA.hy926). Corrected 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) activity results revealed that quercetin and kaempferol have the strongest anti-oxidant capacity in the extract. Both quercetin and kaempferol significantly inhibited the hydrogen peroxide (H2O2)-induced EA.hy926 cell injury and intracellular reactive oxygen species (ROS) generation. In conclusion, we established and validated an UPLC-MS/MC method for the analysis of major bioactive components in the NXQ and demonstrated that its anti-oxidative property may play a critical role in cerebrovascular protection.


Assuntos
Diospyros/química , Medicamentos de Ervas Chinesas/química , Extratos Vegetais/química , Folhas de Planta/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Humanos , Hidroxibenzoatos/química , Quempferóis/química , Perileno/análogos & derivados , Perileno/química , Quercetina/análogos & derivados , Quercetina/química , Espécies Reativas de Oxigênio , Espectrometria de Massas em Tandem
15.
Analyst ; 144(8): 2773-2779, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30869659

RESUMO

With the use of a double-cycle system involving two catalytic reactions by RNase H and DNAzyme, the signal of oligoDNAs has been specifically amplified in an isothermal mode. The precursor of DNAzyme was introduced to the system as a ring-structured and inactivated form, which involves the 6-nt RNA portion being complementary to target oligoDNA. In the presence of target oligoDNA, the RNA portion forms a DNA/RNA hetero-duplex and is cut by RNase H. This scission converts the precursor to catalytically active DNAzyme, which in turn disconnects the molecular beacon to produce the amplified signal. Because the covalent bonds were disconnected to provide discrete structural changes in both cycles, high sensitivity and specificity are obtained, indicating the strong potential of this double catalytic cycle method for versatile applications.


Assuntos
DNA Catalítico/química , DNA de Cadeia Simples/análise , Técnicas de Amplificação de Ácido Nucleico/métodos , Oligonucleotídeos/análise , Ribonuclease H/química , Antraquinonas/química , DNA Catalítico/genética , DNA de Cadeia Simples/genética , Hibridização de Ácido Nucleico , Oligonucleotídeos/genética , Perileno/química , Ribonuclease H/genética
16.
Talanta ; 197: 270-276, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771934

RESUMO

Proteases, as one of the most significant kind of digestive enzymes, are closely related to a variety of physiological processes and diseases. Herein, a black phosphorus nanosheets (BPs) based sensitive fluorometric method for protease detection and inhibitor screening is proposed. The aqueous solution of perylene probe (probe 1) displays a strong fluorescence. BPs, as novel discovered two-dimensional (2D) materials, can adsorb probe 1 through electrostatic interactions, which causes fluorescence quenching of probe 1. Histone can control the interactions between the perylene probe and BPs, which can be further regulated by the introduction of a protease. Thus, the protease activity can be monitored by detecting the fluorescence intensity changes of probe 1. The method is label free, sensitive and selective. As low as 1 ng/mL trypsin can be easily detected.


Assuntos
Corantes Fluorescentes/química , Nanoestruturas/química , Peptídeo Hidrolases/análise , Perileno/química , Fósforo/química , Fluorescência , Corantes Fluorescentes/farmacologia , Humanos , Peptídeo Hidrolases/metabolismo , Perileno/farmacologia
17.
Analyst ; 144(6): 2034-2041, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30702092

RESUMO

A novel sensing strategy for acetylcholinesterase (AChE) and alpha-fetoprotein (AFP) is developed, based on the perylene probe monomer to excimer fluorescence transformation induced by the in situ generation of a metal coordination polymer. In the presence of AChE, acetylthiocholine chloride was hydrolyzed to thiocholine. Ag+ and the produced thiocholine formed a positively charged metal coordination polymer, which induced the aggregation of a negatively charged perylene probe and the formation of probe excimer emission. The intensity ratio of excimer to monomer emission was proportional to the AChE concentration. A sensing method for AChE was thus established with a detection limit of 0.02 mU mL-1. The excimer emission with a large Stokes shift could avoid the interference of background fluorescence from complex biological samples, and thus achieved selective and sensitive detection of AChE. In addition, a fluorescence immunoassay strategy for AFP was then developed. Gold nanoparticles (AuNPs) co-immobilized with acetylcholinesterase and the AFP antibody as the capture and amplification probe were first prepared. In the presence of AFP, the sandwich structure was formed by immunological recognition. The hydrolysis of acetylthiocholine was catalyzed by AChE on the AuNPs, and the metal coordination polymer was then formed which resulted in the aggregation of the perylene probe and the formation of the excimer emission. The proposed sensing method offers a new strategy for the detection of other biomarkers.


Assuntos
Acetilcolinesterase/urina , Complexos de Coordenação/química , Ouro/química , Nanopartículas Metálicas/química , Perileno/química , Polímeros/química , alfa-Fetoproteínas/análise , Técnicas Biossensoriais , Fluorescência , Humanos , Imunoensaio , Limite de Detecção
18.
Mini Rev Med Chem ; 19(11): 923-932, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30663566

RESUMO

OBJECTIVES: Staphylococcus aureus, a Gram-positive bacteria, is ranked second among the causes of hospital infections and is one of the three main causes of food poisoning. In recent times, the spread of antibiotic resistance in S. aureus has become very worrisome. Therefore, research for new effective drugs is important. The present study aims to investigate the phytochemical profiles and antibacterial effects of hydroalcoholic extracts of Origanum vulgare (Lamiaceae family) and Hypericum perforatum (Clusiaceae family) and their active compounds on S. aureus (ATCC 12600) in vitro. METHODS: The identification of phytochemical compounds in both plants was performed by Highperformance liquid chromatography (HPLC), headspace-solid-phase microextraction (HS-SPME) and Fourier-transform infrared spectroscopy (FTIR). To investigate microbial susceptibility, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and disc diffusion method (DAD) were used. Finally, the results of the study were compared with methicillin. RESULTS: Of the 42 combinations of O. vulgare, carvacrol (48%) and of the 38 combinations of H. perforatum, hypericin (46.2%) were the most abundant. The MIC, MBC and DAD of O. vulgare and H. perforatum, carvacrol, hypericin and methicillin were 625, 625, 312.5, 78.12 and 384 µg/mL, 10000, 10000, 2500, 2500 and 384 µg/mL, and 15.66 ± 4.49, 12.66 ± 0.47 and 22 ± 0.81 mm, respectively. CONCLUSION: Due to the significant effects of O. vulgare and H. perforatum and their active components against S. aureus, it is expected that in the future, hypericin, carvacrol and their derivatives can be used as effective antibacterial agents against S. aureus.


Assuntos
Antibacterianos/química , Hypericum/química , Monoterpenos/química , Origanum/química , Perileno/análogos & derivados , Compostos Fitoquímicos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Candida albicans/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Escherichia coli/efeitos dos fármacos , Hypericum/metabolismo , Testes de Sensibilidade Microbiana , Monoterpenos/farmacologia , Origanum/metabolismo , Perileno/química , Perileno/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Microextração em Fase Sólida , Staphylococcus aureus/efeitos dos fármacos
19.
Photochem Photobiol Sci ; 18(2): 487-494, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30534717

RESUMO

Chagas is a parasitic endemic disease caused by the protozoan Trypanosoma cruzi. It represents a strong threat to public health due to its strong resistance against commonly available drugs. We studied the in vitro ability to inactivate the trypomastigote form of this parasite using photodynamic inactivation of microorganisms (or antimicrobial Photodynamic Therapy, aPDT). For this, we chose to use the photosensitizer hypericin (Hyp) formulated in ethanol/water (1% v/v) and Hyp loaded in the dispersion of different aqueous nanocarrier systems. These included polymeric micelles of F-127 and P-123 (both Pluronic™ surfactants), and liposomal vesicles of phospholipid 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC). These systems with Hyp had their activity compared against trypomastigote forms under light and in the dark. Hyp revealed a high level of effectiveness to eradicate protozoa in vitro. Samples at concentrations higher than 0.8 µmol L-1 of Hyp in Pluronic micelles showed efficacy even in the dark, with the EC50 around (6-8) µmol L-1. Therefore, Hyp/Pluronics can be used also as a chemotherapeutic agent. The best result for EC50 is at approximately 0.31 µmol L-1 for illuminated systems of Hyp in F-127 micelles. For Hyp in P-123 micelles under light, the results also led to a low EC50 value of 0.36 µmol L-1. The highest value of EC50 was 2.22 µmol L-1, which was found for Hyp/DPPC liposomes under light. For the Hyp-free (ethanol/water, 1% v/v)/illuminated group, the EC50 value was 0.37 µmol L-1, which also is a value that shows effectiveness. However, in free-form, Hyp is not protected against blood components, unlike when Hyp is loaded into the nanocarriers.


Assuntos
Portadores de Fármacos/química , Nanoestruturas/química , Perileno/análogos & derivados , Trypanosoma cruzi/efeitos dos fármacos , Trypanosoma cruzi/efeitos da radiação , Micelas , Perileno/química , Perileno/farmacologia , Poloxâmero/análogos & derivados , Poloxâmero/química
20.
Molecules ; 23(12)2018 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-30558365

RESUMO

Intramolecular photocyclization of stilbene derivatives (Mallory reaction) is one of the efficient methods for building polycyclic aromatic hydrocarbon (PAH) frameworks, and is also expected to be applicable to synthesis of fluorine-containing PAHs (F-PAHs). In this study, dibenzoanthracene-type (4a) and benzoperylene-type (4b) F-PAHs were synthesized using the Mallory reaction of the 1,4-distyrylbenzene-type π-conjugated molecule (3a), which was prepared by addition-defluorination of available octafluorocyclopentene (OFCP) and aryllithium in three steps. The structure of 4a originating from π⁻π interaction was characterized by X-ray crystallographic analysis. The absorption maxima of UV-Vis spectra and emission maxima of photoluminescence spectra of the PAHs were positioned at a longer wavelength compared to those of the corresponding unsubstituted PAHs, presumably due to the electron-withdrawing nature of perfluorocyclopentene (PFCP) units. The effect of PFCP units in F-PAHs was also studied by time-dependent density functional theory (TD-DFT) calculation.


Assuntos
Benzo(a)Antracenos/química , Benzo(a)Antracenos/síntese química , Flúor/química , Perileno/análogos & derivados , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/síntese química , Modelos Moleculares , Perileno/síntese química , Perileno/química , Espectrofotometria Ultravioleta
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