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1.
Ecotoxicol Environ Saf ; 208: 111621, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396141

RESUMO

The study explored the polycyclic aromatic hydrocarbon tolerance of indigenous biosurfactant producing microorganisms. Three bacterial species were isolated from crude oil contaminated sites of Haldia, West Bengal. The three species were screened for biosurfactant production and identified by 16S rRNA sequencing as Brevundimonas sp. IITISM 11, Pseudomonas sp. IITISM 19 and Pseudomonas sp. IITISM 24. The strains showed emulsification activities of 51%, 57% and 63%, respectively. The purified biosurfactants were characterised using FT-IR, GC-MS and NMR spectroscopy and found to have structural similarities to glycolipopeptides, cyclic lipopeptides and glycolipids. The biosurfactants produced were found to be stable under a wide range of temperature (0-100 °C), pH (4-12) and salinity (up to 20% NaCl). Moreover, the strains displayed tolerance to high concentrations (275 mg/L) of anthracene and fluorene and showed a good amount of cell surface hydrophobicity with different hydrocarbons. The study reports the production and characterisation of biosurfactant by Brevundimonas sp. for the first time. Additionally, the kinetic parameters of the bacterial strains grown on up to 300 mg/L concentration of anthracene and fluorene, ranged between 0.0131 and 0.0156 µmax (h-1), while the Ks(mg/L) ranged between 59.28 and 102.66 for Monod's Model. For Haldane-Andrew's model, µmax (h-1) varied between 0.0168 and 0.0198. The inhibition constant was highest for Pseudomonas sp. IITISM 19 on anthracene and Brevundimonas sp. IITISM 11 on fluorene. The findings of the study suggest that indigenous biosurfactant producing strains have tolerance to high PAH concentrations and can be exploited for bioremediation purposes.


Assuntos
Antracenos/metabolismo , Biodegradação Ambiental , Fluorenos/metabolismo , Tensoativos/metabolismo , Antracenos/química , Bactérias/metabolismo , Fluorenos/química , Glicolipídeos , Hidrocarbonetos/metabolismo , Cinética , Petróleo/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Pseudomonas/metabolismo , RNA Ribossômico 16S/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química
2.
Macromol Rapid Commun ; 41(15): e2000314, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32608550

RESUMO

Light induced degradation of polymers has drawn increasing interest due to the need for externally controllable modulation of materials properties. However, the portfolio of polymers, that undergo precisely controllable degradation, is limited and typically requires UV light. A novel class of backbone-degradable polymers that undergo aerobic degradation in the presence of visible light, yet remain stable against broad-spectrum light under anaerobic conditions is reported. In this design, the polymer backbone is comprised of 9,10-dialkoxyanthracene units that are selectively cleaved by singlet oxygen in the presence of green light as confirmed by NMR and UV/vis spectroscopy. The resulting polymers have been processed by electrohydrodynamic (EHD) co-jetting into bicompartmental microfibers, where one hemisphere is selectively degraded on demand.


Assuntos
Antracenos/química , Polímeros/química , Polímeros/efeitos da radiação , Luz , Espectroscopia de Ressonância Magnética , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Oxigênio Singlete/química , Análise Espectral , Raios Ultravioleta
3.
Environ Toxicol Chem ; 39(9): 1702-1711, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32495402

RESUMO

Recent studies investigating the influence of carbon nanotubes (CNTs) on the bioavailability of organic contaminants have mostly focused on single-solute systems; however, a more likely scenario in the natural environment is a multisolute system where chemical interactions at the surface of the CNT may alter the bioavailability of these chemicals. In the present study bisolute adsorption isotherms of pairs of chemically similar polycyclic aromatic hydrocarbons (PAHs) by multiwalled carbon nanotubes (MWCNTs) were established, in conjunction with quantifying the bioavailability of the 2 competing MWCNT-adsorbed PAHs to Pimephales promelas using bile analysis by high-performance liquid chromatography with fluorescence detection. The results showed that whereas adsorption and bioavailability of chemically similar PAHs (anthracene and phenanthrene, and fluoranthene and pyrene) were the same in a single-solute system, in bisolute systems, PAHs that could better align or flex with the MWCNT surface due to morphological characteristics would outcompete the more rigid or planar PAHs. The bioavailability of individual PAHs in bisolute solutions increased by as much as 50% compared with single-solute solutions. However, the relationship between adsorption (i.e., Kd ) and concentration of PAH in the fish bile was similar in single and bisolute systems. This finding indicates that competitive interactions at the surface of MWCNTs influence bioavailability by way of altering adsorption affinity in a moderately predictable manner. Environ Toxicol Chem 2020;39:1702-1711. © 2020 SETAC.


Assuntos
Cyprinidae/metabolismo , Nanotubos de Carbono/química , Hidrocarbonetos Policíclicos Aromáticos/química , Adsorção , Animais , Antracenos/química , Bile/metabolismo , Disponibilidade Biológica , Fluorenos/química , Fenantrenos/química
4.
J Agric Food Chem ; 68(20): 5579-5585, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32348138

RESUMO

The effective prevention of plant bacterial infections has been complicated and challenged by unceasing bacterial resistance. The application of traditional bactericides has achieved certain effects to alleviate this situation. However, these chemicals also have limitations, such as short half-life in reality, limited bioavailability, and pollutant emission from their formulations. These disadvantages drive the demand for promoting antibacterial therapeutics. Self-assembled nanostructures based on amphiphiles have inherently versatile characteristics, including high durability, good bioavailability, sustained release, and regenerability. As such, they have garnered wide interest because of these advantages that may serve as a feasible platform for the management of pathogenic infections. Flexible tuning of the shapes of these nanostructures by manipulating noncovalent driving forces consequently results in different levels of antibacterial activity. Herein, an antibacterial amphiphile, 1-[11-(9-anthracenylmethoxy)-11-oxoundecyl]pyridinium bromide (AP), was assembled into microfilms in screening medium. Hierarchical nanofibers were constructed by introducing an electron-deficient trinitrofluorenone (TNF) molecule into the assembling system directed by charge-transfer (CT) interactions to further investigate the contribution of aggregate shape to bioactivity. Biological evaluation revealed that antibacterial efficacy improved after CT complex formation. This study provides an innovative platform for developing versatile assembled structures for restraining the propagation of plant pathogens and an improved understanding of the actual interplay between the self-assembly and antibacterial ability of bactericides at the supramolecular level.


Assuntos
Antracenos/química , Antracenos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Doenças das Plantas/microbiologia , Xanthomonas/efeitos dos fármacos , Portadores de Fármacos/química , Nanofibras/química , Xanthomonas/fisiologia
5.
Eur J Med Chem ; 195: 112202, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32302880

RESUMO

We have designed and synthesized anthraquinone containing compounds which have oligopyrrole side chains of varying lengths. These compounds stabilized the G-quadruplex DNA formed in the promoter regions of c-MYC oncogenes selectively over the duplex DNA. These observations were recorded using UV-vis spectroscopic titrations, fluorescence measurements and circular dichroism (CD) spectral titrations. The potency of the compounds to stabilize the G4 DNA has been shown from the thermal denaturation experiments. The compound interacts with c-MYC G-quadruplex DNA through stacking mode as obtained from ethidium bromide displacement assay, cyclic voltammetric titration, and docking experiments. Molecular modeling studies suggested that the stacking of the anthraquinone moiety over the G-tetrad of the G4 structures are responsible for the stability of such quadruplex secondary structure. Furthermore, polymerase stop assay also supported the formation of stable G4 structures in the presence of the above-mentioned compounds. The compounds have shown selective cancer cell (HeLa and HEK293T) cytotoxicity over normal cells (NIH3T3 and HDFa) under in vitro conditions as determined from MTT based cell viability assay. Apoptosis was found to be the mechanistic pathway underlying the cancer cell cytotoxicity as obtained from Annexin V-FITC and PI dual staining assay which was further substantiated by nuclear morphological changes as observed by AO/EB dual staining assay. Cellular morphological changes, as well as nuclear condensation and fragmentation upon treatment with these compounds, were observed under bright field and confocal microscopy.


Assuntos
Antracenos/química , Dimerização , Distamicinas/química , Distamicinas/farmacologia , Quadruplex G/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-myc/genética , Antineoplásicos/química , Antineoplásicos/farmacologia , DNA/química , DNA/genética , Desenho de Fármacos , Modelos Moleculares
6.
Biomater Sci ; 8(11): 3072-3077, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32270804

RESUMO

Triplet-triplet annihilation upconversion (TTA-UC) has great potential in many fields. However, a stable TTA-UC system with adjustable UC efficiency in non-deoxygenated water is still in urgent demand. Here, the first example of short peptide-tuned UC luminescence in water is reported. With only a small amount of peptides, UC chromophores can assemble into tetrahedral microrods with adjustable size and UC efficiency. Successful TTA-UC luminescence of these microrods in water is achieved due to the regular and dense organization of molecular upconversion chromophores tuned by peptides, which allows rapid triplet exciton migration, avoids aggregation-induced quenching and screens molecular oxygen to upconversion chromophores.


Assuntos
Antracenos/química , Metaloporfirinas/química , Compostos Organoplatínicos/química , Peptídeos/química , Fármacos Fotossensibilizantes/química , Platina/química , Leucina/química , Luminescência , Microscopia Confocal , Oxigênio/química , Água
7.
J Chromatogr A ; 1621: 461084, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32303345

RESUMO

This work presents a new triptycene-based dicationic guanidinium ionic liquid (TPG) as the stationary phase for gas chromatography (GC). To our knowledge, this is the first example of employing a dicationic guanidinium ionic liquid (GIL) for chromatographic analyses. As a result, the TPG column exhibited moderate polarity and column efficiency of 3840 plates/m and 3120 plates/m measured by naphthalene and 1-octanol at 120 °C, respectively. Particularly, the TPG column exhibited distinctly advantageous performance for the challenging Grob test mixture and the isomer mixture of phenols and anilines over the monocationic GIL and its counterpart with dicationic immidazolium units (TP-2IL). Also, it showed higher selectivity towards the isomers of alkanes, alcohols, diethylbenzenes, bromotoluenes, bromonitrobenzenes than the commercial DB-35MS column. Moreover, the TPG column achieved improved thermal stability over the GIL column and excellent repeatability with the RSD values of 0.01-0.05% for run-to-run, 0.11-0.24% for day-to-day and 2.4-4.1% for column-to-column. Its application to GC-MS analysis of the essential oil of Mentha haplocalyx proved its good potential for analysis of complex samples.


Assuntos
Antracenos/química , Guanidina/química , Líquidos Iônicos/química , Alcanos/química , Compostos de Anilina/química , Cromatografia Gasosa-Espectrometria de Massas , Líquidos Iônicos/análise , Isomerismo , Mentha/química , Óleos Voláteis/análise , Fenóis/química , Reprodutibilidade dos Testes , Solventes , Temperatura
8.
Int J Pharm ; 580: 119212, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32165226

RESUMO

A new class of non-ionic amphiphiles have been synthesised using a combination of polyethylene glycol (PEG) and oligoglycerol dendrons as hydrophilic units and an alkoxy aryl moiety as hydrophobic unit. The resulting amphiphiles were found to aggregate in aqueous medium. Their aggregation behaviour was studied using dynamic light scattering (DLS), fluorescence spectroscopy, and cryogenic electron microscopy (cryo-TEM). The inner hydrophobic core of these aggregates in aqueous medium is capable of encapsulating lipophilic guest molecules. The encapsulation behaviour was studied using Nile red as a hydrophobic dye as well as Curcumin and Dexamethasone as hydrophobic drug candidates. Furthermore, for biological evaluation, cytotoxicity and cellular uptake was studied using different cancer cell lines. The biomedical application of synthesised amphiphiles was further investigated for dermal drug delivery on excised human skin using Nile red encapsulated in the nanocarrier. The release profile of drug/dye encapsulated amphiphiles was studied under physiochemical conditions in the presence of immobilized lipase Novozym 435.


Assuntos
Antracenos/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Polietilenoglicóis/química , Absorção Cutânea/fisiologia , Células A549 , Antracenos/administração & dosagem , Antracenos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/metabolismo , Células HeLa , Humanos , Células MCF-7 , Nanopartículas/administração & dosagem , Nanopartículas/metabolismo , Técnicas de Cultura de Órgãos , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/metabolismo , Absorção Cutânea/efeitos dos fármacos
9.
Molecules ; 25(6)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192025

RESUMO

Synthesis of the new scorpiand ligand L composed of a [9]aneN3 macrocyclic ring bearing a CH2CH2NHCH2-anthracene tail is reported. L forms both cation (Zn2+) and anion (phosphate, benzoate) complexes. In addition, the zinc complexes of L bind these anions. The equilibrium constants for ligand protonation and complex formation were determined in 0.1 M NaCl aqueous solution at 298.1 ± 0.1 K by means of potentiometric (pH-metric) titrations. pH Controlled coordination/detachment of the ligand tail to Zn2+ switch on and off the fluorescence emission from the anthracene fluorophore. Accordingly, L is able to sense Zn2+ in the pH range 6-10 down to nM concentrations of the metal ion. L can efficiently sense Zn2+ even in the presence of large excess of coordinating anions, such as cyanide, sulphide, phosphate and benzoate, despite their ability to bind the metal ion.


Assuntos
Antracenos/química , Compostos Macrocíclicos/química , Água/química , Zinco/análise , Ânions , Fluorescência , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Ligantes , Prótons , Soluções , Espectrometria de Fluorescência
10.
Inorg Chem ; 59(7): 4567-4575, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32149510

RESUMO

We report the postsynthetic functionalization of Prussian blue (PB) nanoparticles by two different luminophores (2-aminoanthracene and rhodamine B). We show that the photoluminescence properties of the fluorophores are modified by a confinement effect upon adsorption and demonstrate that such multifunctional nanosized systems could be used for in vitro imaging.


Assuntos
Antracenos/química , Ferrocianetos/química , Corantes Fluorescentes/química , Nanopartículas/química , Rodaminas/química , Adsorção , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Humanos , Microscopia de Fluorescência
11.
J Phys Chem Lett ; 11(7): 2701-2707, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32191834

RESUMO

Light-matter interactions have always been a fundamentally significant topic that has attracted much attention. It is important to reveal a fluorophore-plasmon interaction on the nanoscale. However, as a powerful investigative tool, fluorescence spectroscopy still suffers from a limited spectral resolution and the susceptibility to interfering substances. In this work, excitation-emission synchronization-mediated surface-plasmon-coupled emission (EES-SPCE) is proposed to break the bottleneck. By actively screening the energy transitions for observation, an improved spectral resolution has been achieved, which is advantageous to the investigation of the fluorophore-plasmon interactions under different coupling modes. The spectral information related to the plasmonic interactions through tuning vibrational energy levels is clearly distinguished at directional emission angles. EES-SPCE is demonstrated to selectively and efficiently extract the coupled emission from the vibrational resolution, which would open up the opportunity to improve the capability of spectral feature identification and signal collection for practical applications of plasmonic fluorescence spectroscopy.


Assuntos
Antracenos/análise , Pirenos/análise , Antracenos/química , Fluorescência , Estudo de Prova de Conceito , Pirenos/química , Espectrometria de Fluorescência , Ressonância de Plasmônio de Superfície , Vibração
12.
Molecules ; 25(5)2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32138280

RESUMO

A current trend within photo-dynamic therapy (PDT) is the development of molecular systems targeting hypoxic tumors. Thus, type I PDT sensitizers could here overcome traditional type II molecular systems that rely on the photo-initiated production of toxic singlet oxygen. Here, we investigate the cell localization properties and toxicity of two polymeric anthracene-based fluorescent probes (neutral Ant-PHEA and cationic Ant-PIm). The cell death and DNA damage of Chinese hamster ovary cancer cells (CHO-K1) were characterized as combining PDT, cell survival studies (MTT-assay), and comet assay. Confocal microscopy was utilized on samples incubated together with either DRAQ5, Lyso Tracker Red, or Mito Tracker Deep Red in order to map the localization of the sensitizer into the nucleus and other cell compartments. While Ant-PHEA did not cause significant damage to the cell, Ant-PIm showed increased cell death upon illumination, at the cost of a significant dark toxicity. Both anthracene chromophores localized in cell compartments of the cytosol. Ant-PIm showed a markedly improved selectivity toward lysosomes and mitochondria, two important biological compartments for the cell's survival. None of the two anthracene chromophores showed singlet oxygen formation upon excitation in solvents such as deuterium oxide or methanol. Conclusively, the significant photo-induced cell death that could be observed with Ant-PIm suggests a possible type I PDT mechanism rather than the usual type II mechanism.


Assuntos
Fármacos Fotossensibilizantes/química , Polímeros/química , Animais , Antracenos/química , Linhagem Celular Tumoral , Cricetulus , Feminino , Neoplasias Ovarianas , Fotoquimioterapia , Oxigênio Singlete/química
13.
Anal Chem ; 92(5): 3940-3948, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32037802

RESUMO

Here we described an effective recognition strategy using the target-triggered DNA structure transition as an affinity switch for nucleic acid detection based on the strong electrochemiluminescence (ECL) platform of 9,10-diphenylanthracene (DPA) doped perylene (Pe) microcrystals (DPA@Pe MCs). Specifically, the target-triggered rolling-circle amplification (RCA) could generate a long, single-stranded DNA with repeated G-quadruplex units, which would hinder the access of quenching probes due to the steric hindrance effects offered by the DNA structure transition. Using this effective recognition strategy, an ECL biosensor with ultrasensitive and accurate characteristics was proposed to detect microRNA-21, which showed an excellent linear response from 10 aM to 1 pM with the detection limit down to 4.14 aM. The DNA structure transition-induced affinity switch strategy offered a potential applications in clinical diagnosis analysis.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , MicroRNAs/análise , Antracenos/química , Técnicas Eletroquímicas , Eletrodos , Humanos , Limite de Detecção , Medições Luminescentes , Células MCF-7 , MicroRNAs/metabolismo , Microesferas , Técnicas de Amplificação de Ácido Nucleico , Perileno/química
14.
J Chromatogr A ; 1618: 460928, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32008822

RESUMO

This work presents a new triptycene-based stationary phase (TP-PEG) combining the three-dimensional (3D) triptycene (TP) framework with polyethylene glycol (PEG) moieties for gas chromatographic (GC) separations. Its statically coated capillary column showed high column efficiency of 5263 plates/m determined by naphthalene at 120 °C. Its Rohrschneider-McReynolds constants and Abraham solvation system constants were measured to characterize its polarity and molecular interactions with analytes of different types. As evidenced, the TP-PEG column showed high-resolution performance for the isomers of anilines, phenols, halobenzenes and alkanes with distinct advantages over the PEG columns, particularly those critical isomers such as 3,5-/2,3-xylidine (R = 2.94), m-/p-chlorotoluene (R = 1.92), p-/m-cresol (R = 1.89), 2,2-dimethylbutane/2-methylpentane (R = 1.51), 2,2,3-trimethylbutane /2,3-dimethyl pentane (R = 1.74) and 2,3-dimethylpentane/n-heptane (R = 1.92). In addition, it exhibited good column repeatability and reproducibility with the relative standard deviation (RSD) values of 0.02%-0.09% for run-to-run, 0.13%-0.22% for day-to-day and 2.7%-4.1% for column-to-column, respectively, and a wide operational temperature range (30 °C-280 °C) . Its application to GC-MS analysis of the essential oil of Osmanthus fragrans has proven its good potential for practical analysis of complex samples.


Assuntos
Antracenos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/química , Oleaceae/química , Polietilenoglicóis/química , Alcanos/análise , Alcanos/química , Compostos de Anilina/análise , Compostos de Anilina/química , Derivados de Benzeno/química , Isomerismo , Fenóis/análise , Fenóis/química , Reprodutibilidade dos Testes
15.
Colloids Surf B Biointerfaces ; 189: 110876, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32088559

RESUMO

Poly(methacrylate oligoethylene glycol dendron-co-citric acid) (PGCA) that is based on citric acid and oligoethylene glycol (OEG) dendrons is utilized as a nanomaterial for the removal of heavy metal ions from aqueous solution. PGCA shows excellent solubility in aqueous solution and realizes satisfactory removal efficacy for Pb2+ ions; the removal rate exceeds 95 %. In addition, PGCA can be utilized in Chinese herbal decoctions; the removal rate of Pb2+ ions in the ligusticum wallichii decoction exceeds 90 %, meanwhile the concentration of the active ingredient, namely, ferulic acid, is maintained. In this nanoadsorbent, citric acid provides the active site for the chelation of heavy metal ions, and OEG dendron serves as a protective layer that reduces the opportunity for carboxyl groups to be occupied by other ingredients. In summary, nanomaterial PGCA is designed and synthesized successfully that can be applied as a nanoadsorbent for the removal of Pb2+ ions from aqueous solution, especially in Chinese herbal decoctions that have acidic compounds as active ingredients.


Assuntos
Antracenos/química , Ácido Cítrico/química , Etilenoglicóis/química , Chumbo/isolamento & purificação , Ligusticum/química , Nanopartículas/química , Adsorção , Íons/química , Íons/isolamento & purificação , Chumbo/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
16.
Phys Chem Chem Phys ; 22(3): 1115-1121, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31898709

RESUMO

Symmetry-breaking charge transfer (SBCT) is an important process at the early stages of the photoinduced processes in multichromophore systems such as the photosynthetic apparatus. We investigated the photoinduced SBCT dynamics of 9,9'-bianthracene (BA), a representative molecule showing SBCT, by time-resolved fluorescence (TF) with the highest time-resolution and excited-state quantum mechanics/effective fragment potential molecular dynamics (MD) simulation. TF experiments show that the SBCT kinetics matches quantitatively with the solvation function excluding the initial ultrafast component that is assigned to the inertial motion of the solvent. Therefore, it is established that the SBCT of BA is coupled solely with the rotational diffusion of solvent molecules excluding the inertial motion of solvents. MD simulations show that random rotational fluctuation of solvents mostly in the first solvation shell generates a transient electric field as high as 1.0 × 109 V m-1, which provides an asymmetric environment required for the generation of a CT state in this symmetric dimer. Once the CT state is formed, the dipole moment in the solute causes further rotation of solvent molecules leading to an augmented electric field, which in turn further stabilizes the CT state prohibiting the reverse reaction.


Assuntos
Antracenos/química , Processos Fotoquímicos , Solventes/química , Simulação de Dinâmica Molecular , Teoria Quântica , Eletricidade Estática
17.
J Photochem Photobiol B ; 204: 111787, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31958676

RESUMO

The sensitivity for singlet oxygen (1O2) of two convenient 1O2 probes, 1,3-diphenylisobenzofuran (DPBF) and 9,10-Anthracenediyl-bis(methylene)dimalonic acid (ABDA), has been investigated in different aqueous environments. Both probes are commercially available at reasonable cost and can be used with standard UV-vis spectrometers. Although DPBF is not soluble in neat water and is not specific to the detection of 1O2, it has very high, essentially diffusion-limited, reactivity towards 1O2; it can trap up to 50% of all 1O2 created in alcohol/water or micellar solution, and even more when replacing H2O by D2O, which makes it highly useful when the process under investigation does not yield much 1O2. On the other hand, ABDA has a much lower reactivity, reacting with only 2% of the singlet oxygen generated in H2O, as well as a smaller extinction coefficient, resulting in a much smaller spectroscopic response, but is soluble in neat water and is specific for 1O2, allowing for discrimination from other reactive oxygen species. The results presented here not only allow a comparative assessment of the usefulness of the two 1O2 probes, but also provide a reference for an accurate absolute quantification of the amount of 1O2 generated in an experiment from the observed absorbance bleach.


Assuntos
Antracenos/química , Benzofuranos/química , Oxigênio Singlete/análise , Água/química , Óxido de Deutério/química , Luz , Solventes/química , Espectrofotometria
18.
Int J Mol Sci ; 21(1)2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31948078

RESUMO

In this work, we studied the anthracene oxidation by hydroxyl radicals. Hydroxyl radical was generated by reaction of 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin Fe (III) (TPPFe) with hydrogen peroxide under visible radiation at a nitrogen atmosphere. The TPPFe was synthesized by Adler Method followed by metal complexation with Fe (III) chloride hexahydrate. Hydroxyl radical was detected by fluorescence emission spectroscopy and we studied kinetic of anthracene selective oxidation by hydroxyl radicals through the differential method. The TPPFe was characterized by UV-Vis spectrophotometry, Dynamic Light Scattering (DLS) and Scanning Electron Microscopy (SEM) measurements. The results indicated that TPPFE was compound by micro-particles with a size distribution of around 2500 nm. Kinetic results showed that the apparent rate constant for the oxidation of anthracene increased exponentially on as temperature increases, furthermore, the activation energy for the Anthracene oxidation by hydroxyl radicals under visible irradiation was 51.3 kJ/mol. Finally, anthraquinone was the main byproduct generated after oxidation of anthracene by TPP-Fe under visible irradiation.


Assuntos
Antracenos/química , Radical Hidroxila/química , Antracenos/efeitos da radiação , Difusão Dinâmica da Luz , Compostos Férricos/síntese química , Compostos Férricos/química , Peróxido de Hidrogênio/química , Cinética , Luz , Microscopia Eletrônica de Varredura , Nitrogênio , Oxirredução , Porfirinas/síntese química , Porfirinas/química , Porfirinas/efeitos da radiação , Espectrometria de Fluorescência
19.
J Liposome Res ; 30(1): 21-36, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30741049

RESUMO

Mammary gland tumour has the highest incidence rate and mortality in women, worldwide. The present study envisaged a molecularly targeted nanostructured lipid carrier (NLCs) for doxorubicin (Dox) delivery capable of inducing cellular apoptosis in mammary gland tumour. NLCs were prepared utilizing Perilla frutescens oil (54-69% ω3-fatty acid) as liquid lipid to enhance entrapment of Dox through molecular ion pairing. Biotin decorated NLCs (b-Dox-NLCs) were evaluated in vitro and in vivo. The b-Dox-NLCs showed particle size of 105.2 ± 3.5 nm, zeta potential -35 ± 2 mV, entrapment 99.15 ± 1.71%, drug content 19.67 ± 2.6 mg.g-1, biotin content 5.85 ± 0.64 µg.g-1 and drug release 98.67 ± 2.43% (facilitated by acidic microenvironment) respectively. MTT assay and Flow cytometric analysis revealed higher anti-proliferative capability of b-Dox-NLCs to force apoptosis in MCF-7 cell line vis-à-vis marketed Dox, evidenced by reactive oxygen species level and mitochondrial membrane potential mediated apoptosis. Enhanced antitumor targeting, therapeutic safety and efficacy was exhibited by b-Dox-NLCs, as investigated through tumour volume, animal survival, weight variation, cardiotoxicity and biodistribution studies in 7,12-Dimethylbenz[a]anthracene induced mammary gland tumour. Immunoblotting assay demonstrated b-Dox-NLCs downregulated anti-apoptotic proteins, i.e. bcl-2, MMP-9 while upregulated pro-apoptotic proteins, i.e. caspase-9, p16 and BAX. The experimental results suggest that biotinylated ω3-fatty acid augmented NLCs loaded with Dox are capable of inducing programmed cell death in mammary tumour and can be utilized as safe and effective delivery system with enhanced potential for mammary gland carcinoma therapy.


Assuntos
Antineoplásicos/química , Biotina/química , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/química , Ácidos Graxos/química , Lipossomos/química , Nanoestruturas/química , Animais , Antracenos/química , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos , Biotina/metabolismo , Cardiotoxicidade/metabolismo , Preparações de Ação Retardada/química , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Composição de Medicamentos , Liberação Controlada de Fármacos , Feminino , Humanos , Células MCF-7 , Membranas Mitocondriais/metabolismo , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície , Distribuição Tecidual , Microambiente Tumoral/efeitos dos fármacos
20.
J Chromatogr A ; 1614: 460714, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761436

RESUMO

Developing highly selective stationary phases is essential to address the issues for separation of analytes with similar properties and various components in complex samples. Herein, we report a new triptycene-based material functionalized with polycaprolactone moieties (TP-PCL) as the stationary phase with high-resolution performance for gas chromatography (GC). The TP-PCL capillary column exhibited column efficiency of 5555 plates/m and moderate polarity. On the column, dozens of mixtures of positional and structural isomers can be well resolved, involving benzene derivatives with varying substituents (alkyl, halo, nitro, hydroxyl, amino), naphthalene derivatives, alkanes and alcohols. It exhibits advantageous performance for high resolution of the critical pairs of alkylbenzenes, phenols, anilines and alkanes over the PCL column and commercial DB-35 MS column with similar polarity. Moreover, the TP-PCL column showed excellent separation repeatability and reproducibility with RSD values of 0.02%-0.07% for run-to-run (n = 4), 0.11%-0.18% for day-to-day (n = 4) and 2.1%-4.7% for column-to-column (n = 4). In addition, it exhibited distinctly enhanced thermal stability in contrast to the PCL column. Its application to analysis of the essential oil from Artemisiae argyi proves its good potential for practical use.


Assuntos
Antracenos/química , Cromatografia Gasosa/métodos , Poliésteres/química , Álcoois/análise , Álcoois/química , Alcanos/análise , Alcanos/química , Compostos de Anilina/análise , Compostos de Anilina/química , Derivados de Benzeno/análise , Derivados de Benzeno/química , Isomerismo , Naftalenos/análise , Naftalenos/química , Fenóis/análise , Fenóis/química , Reprodutibilidade dos Testes
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