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1.
Molecules ; 26(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361832

RESUMO

In recent times, researchers have aimed for new strategies to combat cancer by the implementation of nanotechnologies in biomedical applications. This work focuses on developing protein-based nanoparticles loaded with a newly synthesized NIR emitting and absorbing phthalocyanine dye, with photodynamic and photothermal properties. More precisely, we synthesized highly reproducible bovine serum albumin-based nanoparticles (75% particle yield) through a two-step protocol and successfully encapsulated the NIR active photosensitizer agent, achieving a good loading efficiency of 91%. Making use of molecular docking simulations, we confirm that the NIR photosensitizer is well protected within the nanoparticles, docked in site I of the albumin molecule. Encouraging results were obtained for our nanoparticles towards biomedical use, thanks to their negatively charged surface (-13.6 ± 0.5 mV) and hydrodynamic diameter (25.06 ± 0.62 nm), favorable for benefitting from the enhanced permeability and retention effect; moreover, the MTT viability assay upholds the good biocompatibility of our NIR active nanoparticles. Finally, upon irradiation with an NIR 785 nm laser, the dual phototherapeutic effect of our NIR fluorescent nanoparticles was highlighted by their excellent light-to-heat conversion performance (photothermal conversion efficiency 20%) and good photothermal and size stability, supporting their further implementation as fluorescent therapeutic agents in biomedical applications.


Assuntos
Indóis/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Soroalbumina Bovina/química , Proliferação de Células , Feminino , Humanos , Indóis/química , Luz , Simulação de Acoplamento Molecular , Nanopartículas/química , Neoplasias Ovarianas/patologia , Fármacos Fotossensibilizantes/química , Espectroscopia de Luz Próxima ao Infravermelho , Células Tumorais Cultivadas
2.
Antioxidants (Basel) ; 10(5)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067035

RESUMO

This study aimed to obtain and characterize extracted hemp oil enriched in cannabidiol (CBD) by decarboxylation of cannabidiolic acid (CBDA) and to give new insights into its antioxidant and anticancer effects. Optimization of CBDA decarboxylation in hemp oil was performed, and CBD and CBDA contents and purities were determined by flash chromatography, 1H- and 13C-NMR. The antioxidant properties of CBD-enriched oil were investigated by Fe2+ chelating activity, Fe3+ reducing antioxidant power assay, O2●- scavenging activity, HO● scavenging ability and lipid peroxidation inhibitory assay, and its cytotoxicity, apoptosis- and oxidative stress-inducing effects on NHDF, MeWo, HeLa, HepG2 and HOS cells were determined. The CBD concentration in hemp oil was increased by CBDA soft decarboxylation optimized at 90 °C, for 1 h and the resulting oil was capable of reducing iron, scavenging free radicals and inhibiting lipid peroxidation in cell-free oxidative conditions. CBD-enriched oil promoted NHDF proliferation at up to 15 µg CBD/mL, while inducing apoptosis and ROS production and modulating antioxidant enzymes' gene expression in cancer cells, being selective for osteosarcoma cells, and induced apoptosis by p53- and ROS-independent mechanisms. CBD-enriched hemp oil demonstrated antioxidant properties in oxidative conditions and promoted normal fibroblasts' proliferation, while inducing apoptosis and ROS production in cancer cells.

4.
Molecules ; 25(19)2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32987884

RESUMO

We have designed and synthesized a series of novel, supramolecular, long-lived fluorescent probes based on the host-guest inclusion complexes formation between fluorescent indolizinyl-pyridinium salts and ß-cyclodextrin. Fluorescence and electrospray ionisation mass spectrometry experiments, supported by theoretical molecular docking studies, were utilized in the monitoring of the inclusion complexes formation, evidencing the appearance of corresponding 1:1 and 1:2 species. Additionally, the influence of the guest molecule over the aggregation processes of the cyclodextrin inclusion complexes was investigated by transmission electron microscopy. The absence of cytotoxicity, cellular permeability, long-lived intracellular fluorescence, and in time specific accumulation within acidic organelles identified the investigated supramolecular entities as remarkable candidates for intracellular fluorescence probes. Co-staining experiments using specific organelle markers revealed the fact that, after a 24-h incubation period, the inclusion complexes accumulate predominantly in lysosomes rather than in mitochondria. This study opens new possibilities for a broad range of fluorescent dyes with solubility and high toxicity issues, able to form inclusion complexes with ß-cyclodextrin, to be tested as intracellular fluorescence probes.


Assuntos
Ciclodextrinas/química , Corantes Fluorescentes/química , Simulação de Acoplamento Molecular , Espectrometria de Fluorescência
5.
Sci Rep ; 10(1): 6591, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313258

RESUMO

The paper aims to investigate the cytotoxic effect on tumor cells of irradiated AuNPs in green light and subsequently functionalized with HS-PEG-NH2. The toxicity level of gold conjugates after their functionalization with DOX and TAT peptide was also evaluated. The AuNPs were prepared using the modified Turkevich method and exposed to visible light at a wavelength of 520 nm prior their PEGylation. The optical properties were analyzed by UV-vis spectroscopy, the surface modification was investigated using FTIR and XPS spectroscopies and their sizes and morphologies were evaluated by TEM and DLS techniques. DOX and TAT peptide were linked to the surface of PEGylated AuNPs by reacting their amino groups with glycidyloxypropyl of PEGylated DOX or TAT conjugates under mild conditions at room temperature and in the presence of ethanol as catalyst. The conjugates containing DOX or DOX and TAT have been characterized by fluorescence and FTIR techniques. The changes of electrochemical features were observed using cyclic voltammetry, suggesting a better stability of irradiated nanoparticles. By mass spectrometry it was confirmed that the compounds of interest were obtained. The cell viability test showed that irradiated and non-irradiated nanoparticles coated with PEG are not toxic in normal cells. Tumor cell viability analysis showed that the PEGylated nanoparticles modified with DOX and TAT peptide were more effective than pristine DOX, indicating cytotoxicity up to 10% higher than non-irradiated ones.


Assuntos
Doxorrubicina/farmacologia , Produtos do Gene tat/farmacologia , Nanopartículas Metálicas/química , Osteossarcoma/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Produtos do Gene tat/química , Ouro/química , Humanos , Osteossarcoma/genética , Osteossarcoma/patologia , Peptídeos/química , Peptídeos/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
6.
J Ethnopharmacol ; 252: 112559, 2020 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31935497

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Crataegus leaves, flowers and fruits have been traditionally used to improve blood circulation, numerous preclinical and clinical studies supporting the cardiovascular benefits of Crataegus preparations. In this respect, there is very limited data on Crataegus pentagyna; in addition, the chemical profile of this species is still incompletely elucidated. AIM OF THE STUDY: The objective of this study was to examine the cardiovascular benefits of Crataegus pentagyna Waldst. et Kit. ex Willd. (small-flowered black hawthorn, Rosaceae) extracts (leaf, flower and fruit ethyl acetate extracts) and the underlying mechanisms. We hypothesized that C. pentagyna extracts might exert vasodilatory effects and inhibit arginase activity due, in large part, to their polyphenolic constituents. MATERIALS AND METHODS: C. pentagyna extracts induced-relaxation and the mechanisms involved were studied ex vivo in isolated aortic rings from Sprague-Dawley rats. The inhibitory effects on bovine liver arginase I were assessed by an in vitro assay. Metabolite profiling of C. pentagyna extracts was performed and the most endothelium- and nitric oxide synthase-dependent; flower extract additionally reduced Ca2+ entry and, to a lesser extent, Ca2+ release from the sarcoplasmic reticulum. C. pentagyna proved to be an important source of arginase inhibitors with potential benefits in endothelial dysfunction that remains to be explored.


Assuntos
Aorta Torácica/efeitos dos fármacos , Arginase/antagonistas & inibidores , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Vasodilatadores/farmacologia , Animais , Aorta Torácica/fisiologia , Cálcio/fisiologia , Crataegus , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Flores , Frutas , Masculino , Folhas de Planta , Canais de Potássio/fisiologia , Ratos Sprague-Dawley
7.
Food Chem Toxicol ; 133: 110764, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437471

RESUMO

The present study investigated the effects of Cornus mas, Sorbus aucuparia and Viburnum opulus fruit extracts on arginase activity and arterial vasodilation. V. opulus fruit extract exerted the highest vasorelaxant activity in phenylephrine precontracted rat aortic rings (EC50 = 6.31 ±â€¯1.61 µg/mL) and a significant inhibition of arginase (IC50 = 71.02 ±â€¯3.06 µg/mL). By contrast, S. aucuparia and C. mas fruit extracts showed no important anti-arginase activity and a significantly weaker activity in the rat aortic rings relaxation assay (EC50 = 100.9 ±â€¯11.63 and 78.52 ±â€¯8.59 µg/mL, respectively). For all extracts, the main mechanism of vasodilation was proven to be endothelium-dependent. HPLC-ESI-Q-TOF-MS/MS studies revealed a very complex metabolite profiling in all three extracts with chlorogenic acid accounting for 30.89, 0.72 and 2.03 mg/g in V. opulus, C. mas and S. aucuparia fruit extracts, respectively. All extracts were declared non-toxic in the brine shrimp acute toxicity test. Our study highlights potential benefits of V. opulus fruit extract in diseases associated with endothelial dysfunction and impaired vasodilation.


Assuntos
Arginase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Frutas/química , Extratos Vegetais/farmacologia , Vasodilatadores/farmacologia , Animais , Aorta/efeitos dos fármacos , Artemia/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cornus/química , Endotélio/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Masculino , Metaboloma , Extratos Vegetais/toxicidade , Ratos Sprague-Dawley , Sorbus/química , Espectrometria de Massas em Tandem , Vasodilatadores/toxicidade , Viburnum/química
8.
Adv Exp Med Biol ; 1140: 685-701, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31347079

RESUMO

An important and well-designed solution to overcome some of the problems associated with new drugs is provided by the molecular encapsulation of the drugs in the cyclodextrins (CDs) cavity, yielding corresponding inclusion complexes (ICs). These types of non-covalent complexes are of current interest to the pharmaceutical industry, as they improve the solubility, stability and bioavailability of the guest molecules. This review highlights several methods for cyclodextrin ICs preparation and characterization, focusing mostly on the mass spectrometry (MS) studies that have been used for the detection of noncovalent interactions of CDs inclusion complexes and binding selectivity of guest molecules with CDs. Furthermore, the MS investigations of several ICs of the CD with antifungal, antioxidants or fluorescent dyes are presented in greater details, pointing out the difficulties overcome in the analysis of this type of compounds.


Assuntos
Química Farmacêutica/métodos , Ciclodextrinas/análise , Espectrometria de Massas , Solubilidade
9.
Environ Sci Pollut Res Int ; 26(19): 19684-19696, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31081534

RESUMO

Doxorubicin (DOX) is a chemotherapeutic agent from anthracycline class, which acts unselectively on all cells; thus, it may have genotoxic and/or mutagenic effects and cause serious environmental problems. Herein, the decomposition of a diluted solution of DOX hydrochloride for injection has been investigated under photo-oxidative conditions, in ambient light and without pH modification, using hydrogen peroxide as oxidizing agent and hydrophobic siloxane-based metal-organic frameworks (MOFs) as heterogeneous catalysts. The kinetics of the photodegradation process was followed by UV-Vis spectroscopy and by ESI-MS. According to UV-Vis data, two pseudo-first-order kinetic steps describe the process, with rate constants in the order of 10-3-10-2 min-1 for the rate-determining one. ESI-MS provided more accurate information, with a rate constant of 2.6 · 10-2 min-1 calculated from the variation of DOX ion abundance. Complete decomposition of DOX was achieved after 120 min in the shade and after only 20 min by exposure to sunlight. The analysis of the residual waters by mass spectrometry and 1D and 2D NMR spectroscopy showed complete disappearance of DOX in all cases, excluded any anthracycline species, which are destroyed in the tested conditions, and proved formation of an un-harmful compound-glycerol, while no trace of metal was detected by XRF. Preliminary data also showed decomposition of oxytetracycline in similar conditions. By this study, we bring into attention a less-addressed pollution issue and we propose a mild and effective method for the removal of drug emerging pollutants.


Assuntos
Doxorrubicina/análise , Luz , Estruturas Metalorgânicas/química , Fotólise , Siloxanas/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Catálise , Doxorrubicina/efeitos da radiação , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Cinética , Oxidantes/química , Oxirredução , Poluentes Químicos da Água/efeitos da radiação
10.
Int J Biol Macromol ; 131: 134-146, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30857965

RESUMO

Currently, biosorption is considered a leading-edge environmentally-friendly method for the low-cost remediation of wastewaters contaminated with metal ions. However, the safe disposal of metal-loaded biosorbents is still a challenging issue. In this context, our major objective was to explore the possibility of "waste minimization" by reusing the metal-loaded biosorbents in further environmental applications, particularly into the oxidative catalysis of dyes. Thus, the decolourisation efficiency (DE) of Methyl Orange (MO) in aqueous solutions under ambient light using copper-imprinted chitosan-based composites in comparison to non-imprinted ones was investigated in this work. The MO degradation was established first in the absence of any co-catalyst, when a DE value of 95.3% was achieved by the ion-imprinted catalysts within 360 min of reaction, compared to only 67.4% attained by the non-imprinted ones. Under Fenton-like conditions, the apparent degradation rate constant was seventy times higher, the DE increasing within 40 min to about 98.6%, and 70.5% respectively, whereas the content of co-catalyst (H2O2) was significantly lowered compared to other reported studies. The straightforward preparation of copper-loaded composites, along with their excellent stability and high efficiency even after four consecutive reaction runs support our ion-imprinted systems as potential catalysts for dye removal by oxidative decolourisation treatments.


Assuntos
Quitosana/química , Cobre/química , Íons/química , Nanoestruturas/química , Adsorção , Algoritmos , Catálise , Modelos Teóricos , Nanoestruturas/ultraestrutura , Porosidade , Análise Espectral , Poluentes Químicos da Água/química , Purificação da Água
11.
PLoS One ; 13(8): e0202441, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30153262

RESUMO

Young wheat plantlets (wheatgrass), represent a significant source of minerals, enzymes, vitamins, while also rich in phenolics and chlorophylls, with considerable bioactivities. As the biosynthesis of such compounds may be influenced by growth conditions, the current research assesses wheatgrass composition in soil based and hydroponic systems, using water with different elemental composition. FTIR spectroscopy did not reveal significant variations between juice and extracts cultivated in different setups. Surface elemental composition indicated higher Na, P, Si concentrations in hydroponic plants, while AAS analyses showed increased Ca and Mn in soil presence. HPLC-MS of extracts showed that soil and spring water increased chlorophyll and hydroxychlorophyll a concentrations. Phenolic contents were higher in hydroponic plants, while maximum values were recorded for spring water. Radical scavenging activity was stimulated by the use of spring water. Results indicate that wheatgrass with improved mineral and macromolecular composition may be obtained using accessible cultivation setups.


Assuntos
Fósforo/metabolismo , Polifenóis/metabolismo , Dióxido de Silício/metabolismo , Sódio/metabolismo , Triticum/crescimento & desenvolvimento
12.
Food Chem Toxicol ; 108(Pt B): 429-437, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28174115

RESUMO

Ramaria largentii Marr & D. E. Stuntz (orange coral mushroom) is a wild edible mushroom whose chemical composition and bioactivity have not been investigated. Herein, we present a study on the phenolic constituents, antioxidant and antigenotoxic effects of a hydromethanolic extract of the fruiting bodies. Total phenolic content, estimated by Folin-Ciocalteu assay, was found to be 42.33 ± 0.18 mg GAE/g. Protocatechuic and vanillic acids were detected by HPLC-DAD-ESI-MS. The extract showed good free radical scavenging and reducing capacities (EC50 = 64.3 ± 0.2 and 61.54 ± 0.46 µg/mL, respectively). In normal Vero cells, the extract (100, 200 and 300 µg/mL) showed no genotoxic potential and moreover, almost completely protected DNA against H2O2-induced damage (2.09-7.91% tail DNA) (24 and 48 h pre-treatment). Taken together, the results of our study show that Ramaria largentii extract is devoid of genotoxicity and has a remarkable DNA protective activity against H2O2-induced damage.


Assuntos
Agaricales/química , Antioxidantes/farmacologia , Animais , Antioxidantes/química , Araquidonato 15-Lipoxigenase/metabolismo , Sobrevivência Celular , Quelantes , Chlorocebus aethiops , Análise de Alimentos , Ferro , Inibidores de Lipoxigenase/química , Inibidores de Lipoxigenase/farmacologia , Testes de Mutagenicidade , Oxirredução , Fenóis/química , Fenóis/farmacologia , Romênia , Células Vero
13.
Nat Prod Res ; 28(22): 2076-80, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24931335

RESUMO

The aim of this study was to investigate the phenolic content and antibacterial activity of the methanol extract from Helichrysum arenarium (L.) Moench subsp. arenarium inflorescences against lower respiratory tract pathogens (standard strains and clinical isolates). The extract was characterised by a total phenolic content of 160.17 mg/g. Several caffeic acid conjugates (chlorogenic acid and dicaffeoylquinic acids) and flavonoids (apigenin, naringenin, apigenin-7-O-glucoside and naringenin-O-hexosides) were identified as major constituents by HPLC-DAD-ESI-MS. Staphylococcus aureus ATCC 25923 was more susceptible to Helichrysum extract than Streptococcus pneumoniae ATCC 49619 (minimum inhibitory concentration [MIC] = 0.62  and 1.25 mg/mL, respectively). The extract exhibited similar antibacterial effects against methicillin-resistant S. aureus and penicillin-resistant S. pneumoniae clinical isolates (MIC = 2.5 mg/mL) displaying a higher activity against ampicillin-resistant Moraxella catarrhalis isolate (MIC = 0.15 mg/mL). The combination with ciprofloxacin exhibited additivity against both standard strains (fractional inhibitory concentration [FIC] index = 0.75 and 0.73) and S. aureus isolates (FIC index = 0.62) and synergy against S. pneumoniae isolates (FIC index = 0.5).


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Helichrysum/química , Fenóis/farmacologia , Sistema Respiratório , Antibacterianos/química , Ciprofloxacina/farmacologia , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Moraxella catarrhalis/efeitos dos fármacos , Fenóis/análise , Pseudomonas aeruginosa/efeitos dos fármacos , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pneumoniae/efeitos dos fármacos
14.
Chemistry ; 20(22): 6678-83, 2014 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-24756773

RESUMO

Herein, we consider Müller's spherical, porous, anionic, molybdenum oxide based capsule, (NH4)42[{(Mo(VI))Mo(VI)5O21(H2O)6}12{Mo(V)2O4(CH3COO)}30]⋅10 CH3COONH4⋅300 H2O≡(NH4)42⋅1 a⋅crystal ingredients≡1, {Mo132}, as an effective sugar-decorated nanoplatform for multivalent lectin recognition. The ion-exchange of NH4(+) ions of 1 with cationic-sugars, D-mannose-ammonium chloride (2) or D-glucose-ammonium chloride (3) results in the formation of glyconanocapsules (NH4)(42-n)2n⋅1 a and (NH4)(42-m)3m⋅1 a. The Mannose (NH4)(42-n)2n⋅1 a capsules bind selectively Concanavalin A (Con A) in aqueous solution, giving an association avidity constant of K(a)(multi)=4.6×10(4) M(-1) and an enhancement factor of ß=K(a)(multi)/K(ass)(mono)=21.9, reminiscent of the formation of "glycoside clusters" on the external surface of glyconanocapsule. The glyconanocapsules (NH4)(42-n)2n⋅1 a and (NH4)(42-m)3m⋅1 a self-assemble in "hybrid multilayers" by successive layer-by-layer deposition of (NH4)(42-n)2n⋅1 a or (NH4)(42-m)3m⋅1 a and Con A. These architectures, reminiscent of versatile mimics of artificial tissues, can be easily prepared and quantified by using quartz crystal microgravimetry (QCM). The "biomimetic hybrid multilayers" described here are stable under a continual water flow and they may serve as artificial networks for a greater depth of understanding of various biological mechanisms, which can directly benefit the fields of chemical separations, sensors or storage-delivery devices.


Assuntos
Materiais Biocompatíveis/química , Concanavalina A/química , Molibdênio/química , Nanocápsulas/química , Cloreto de Amônio/química , Glucose/química , Cinética , Manose/química , Ligação Proteica , Técnicas de Microbalança de Cristal de Quartzo , Compostos de Tungstênio/química
15.
Mater Sci Eng C Mater Biol Appl ; 34: 176-85, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24268247

RESUMO

Phosphate diacrylates (CO-DAP, TMP-DAP) based on castor oil or trimethylolpropane were synthesized and evaluated in dental adhesive formulations in comparison with 3-acryloyloxy-2-hydroxypropyl methacrylate phosphate (AMP-P). In an attempt to promote antibacterial activity, another photopolymerizable monomer (TCS-UMA) containing 5-chloro-2-(2,4-dichlorophenoxy)phenol moiety (triclosan) was prepared and incorporated in adhesive resins. Each of these monomers had a molecular structure confirmed by spectral methods. The photopolymerization rates for monomers (0.063-0.088s(-1)) were lower than those determined in the monomer combinations (0.116-0.158s(-1)) incorporating phosphate diacrylate (11wt.%), BisGMA (33wt.%), TEGDMA (10wt.%), UDMA (10wt.%) and HEMA (15wt.%), the degree of conversion varying between 63.4 and 74.5%. The formed copolymers showed high values for water sorption (18.65-57.02µg/mm(3)) and water solubility (3.51-13.38µg/mm(3)), and the contact angle was dependent on the presence of CO-DAP (θF1: 66.67°), TMP-DAP (θF2: 55.05°) or AMP-P (θF3: 52.90°) in the photocrosslinked specimens compared to the sample without phosphate monomer (θF4: 82.14°). The scanning electron microscopy image of the dentin-resin composite interface after applying our F1 formulation (pH: 4.1) and its light-curing for 20s supports the evidence of the formation of the hybrid layer with the tooth structure created by self-etching approach, with no gaps or cracks in the adhesive. A comparative analysis of the adhesion achieved with commercial adhesive systems (Single Bond Universal, C-Bond) rather indicates similarities than differences between them. The addition of triclosan methacrylate (1wt.%) into the formulation inhibited the bacterial growth of the Streptococcus mutans and Escherichia coli in the direct contact area due to the covalently linked antibacterial monomer.


Assuntos
Acrilatos/química , Cimentos Dentários/química , Luz , Fosfatos/química , Polimerização/efeitos da radiação , Triclosan/química , Acrilatos/síntese química , Antibacterianos/farmacologia , Resinas Compostas/química , Escherichia coli/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Fosfatos/síntese química , Solubilidade , Espectrometria de Massas por Ionização por Electrospray , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Streptococcus mutans/efeitos dos fármacos , Triclosan/farmacologia , Água/química
16.
Beilstein J Org Chem ; 9: 1285-95, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23843924

RESUMO

Full characterization of fullerenol C60(OH)24 by HPLC ESI-MS in negative and positive ionization modes was achieved. Fragmentor voltage and capillary voltage were optimized in order to obtain a good signal stability and the best peak intensity distribution for the fullerenol C60(OH)24 in both negative and positive modes. While the predominant base peak observed for C60(OH)24 in the negative ionization mode was [M - H](-) at m/z 1127, those observed in the positive mode were multiply charged [M - H2O + 4H](4+) at m/z 279 and [M - 12H2O + 2NH3 + 6H](6+) at m/z 158.

17.
Chem Commun (Camb) ; 49(29): 3004-6, 2013 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-23459764

RESUMO

Multivalent biorecognition of lectin layers by glyconanoparticle sugar-clusters has been used to generate multilayer nanoplatform architectures in a QCM sensing setup.


Assuntos
Carboidratos/análise , Lectinas/análise , Nanopartículas/química , Técnicas de Microbalança de Cristal de Quartzo , Concanavalina A/análise , Concanavalina A/metabolismo , Lectinas/metabolismo
18.
Results Pharma Sci ; 1(1): 27-37, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-25755979

RESUMO

A novel inclusion complex of the propiconazole nitrate (NO3PCZ) with ß-cyclodextrin (ß-CD) was prepared by treatment of propiconazole (PCZ) with an acidic nitrating agent. The formation of NO3PCZ and its inclusion complex with ß-CD has been studied by NMR, ESI-MS, TGA, DSC methods. Using the undecoupled signal in the HMBC correlation spectra, almost identical coupling constants of CH from trizolic ring of PCZ and NO3PCZ compounds ((1)J(HC)3=207 Hz, (1)J(CH)5=214 Hz, for PCZ; (1)J(HC)3=208 Hz and (1)J(CH)5=215 Hz, for NO3PCZ) were determined, confirming that the geometry of the heterocyclic skeleton is identical in both the forms. The 1:1 stoichiometry of the complex was determined by ESI-MS and was confirmed using Scott's equation in DMSO and Higuchi and Connors equation in water. The solubility curve obtained for NO3PCZ in presence of ß-CD in distilled water was constructed, resulting in a solubility diagram of AL type. Solubility of NO3PCZ in water was determined by DLS studies. The results showed that NO3PCZ was encapsulated within the ß-CD cavity with a binding constant of 330 M-1 in DMSO and 975 M-1 in water. Preliminary pharmacological studies showed higher antifungal activities for NO3PCZ and its inclusion complex, compared with its PCZ analog. The acute toxicity of the complex is smaller than the pure or modified drug, recommending the inclusion complex as future promising therapeutic agents.

19.
J Mater Sci Mater Med ; 21(11): 3009-18, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20820886

RESUMO

Ketoprofen (Ket) was intercalated into layered double hydroxides (ZnAlLDH and MgAlLDH) using the ionic exchange method. The drug intercalation was confirmed by X-ray diffraction (XRD) and FTIR spectroscopy. Ket release from the inorganic matrix was studied at pH 7.4 in continuous regime with a flow rate of 0.5 and respectively 1.0 ml/min. The kinetical data were interpreted using the Ritger and Peppas model. The data prove that the release kinetics and mechanism depend on the eluent flow rate. Quantification of gastric tolerance shows that the ulcerogenic effect of the intercalated drug is lower than the one of the raw Ket. The antinociceptive effect of both formulations was studied by the hot-plate method performed on mice. The MgAlLDH_Ket formulation shows a tendency towards a stronger antinociceptive effect than its ZnAlLDH_Ket counterpart during the 210 min recorded period.


Assuntos
Química Farmacêutica/métodos , Portadores de Fármacos/química , Hidróxidos/química , Cetoprofeno/farmacocinética , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacocinética , Portadores de Fármacos/metabolismo , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/patologia , Hidróxidos/metabolismo , Cetoprofeno/administração & dosagem , Cetoprofeno/efeitos adversos , Masculino , Camundongos , Medição da Dor , Polímeros/química , Polímeros/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/epidemiologia , Resultado do Tratamento , Difração de Raios X
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