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1.
Artigo em Inglês | MEDLINE | ID: mdl-38538871

RESUMO

Chromium aluminum carbide (Cr2AlC) MAX phase and Cr2CTx (MXene-Cr) were synthesized by the pressureless sintering method and hydrothermal method, respectively. In addition to this, the free radical scavenging activities (FRSA) of MAX-Cr phase and MXene-Cr compounds were tested and compared with ascorbic acid and trolox as standard compounds. The obtained FRSA results of MAX-Cr phase and MXene-Cr were 42.82 and 59.64%, respectively, at 100 mg/L concentration. MXene-Cr showed a 66.90% inhibitory effect on α-amylase at 200 mg/L. The DNA nuclease activity of compounds was determined to be extremely satisfactory at 50, 100, and 200 mg/L concentrations. Moreover, the prepared MAX-Cr phase and MXene-Cr were investigated for antimicrobial activity against six bacterial and two fungal strains by the broth microdilution method. Compounds provided more significant inhibition against Gram-positive bacteria than Gram-negative bacteria and fungi. MAX-Cr phase and MXene-Cr almost completely inhibited microbial cell viability at a 25 mg/L concentration. Additionally, MXene-Cr showed 89.86% and 87.01% antibiofilm activity against S. aureus and P. aeruginosa, respectively, while the antibiofilm activity of the MAX-Cr phase was over 90%.

2.
Chem Biodivers ; 20(12): e202301411, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38015743

RESUMO

Copper oxide nanoparticles (CuONPs) were synthesized using a rapid, eco-friendly, cost-effective, efficient, and biological method employing aqueous Agaricus bisporus extract as a capping and reducing agent. The formation of CuONPs was checked by UV-vis spectroscopy and was characterized by X-ray diffraction analysis (XRD), dynamic light scattering spectroscopy (DLS), transmission electron microscopy (TEM), and surface area and porosimetry analyzer. The characterization results showed that the synthesized nanoparticles had a spherical-like appearance and a crystal structure with 40-100 nm particle size. The green synthesized CuONPs were found to be an excellent and sustainable heterogeneous catalyst (TOF up to 29700 h-1 ) for the Suzuki C-C coupling of aryl halides with phenylboronic acid in a very short reaction time (10 minutes). Moreover, the easily recovered catalyst can be reused five times with just a negligible reduction in catalytic behavior.


Assuntos
Nanopartículas Metálicas , Nanopartículas Metálicas/química , Catálise , Cobre/química , Extratos Vegetais/química
3.
Dalton Trans ; 52(29): 9993-10004, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37403542

RESUMO

In this study, a glycerol group substituted bis(2-pyridylamino)isoindoline (BPI-OH) ligand and its metal complexes (M = Pt, Cu and Co) were synthesized. Characterization of all new compounds was carried out using FT-IR, NMR, UV-Vis, and mass spectroscopy. Various biological activities of BPI derivatives were also tested. The antioxidant activities of BPI-OH, Pt-BPI-OH, Cu-BPI-OH, and Co-BPI-OH were 87.52 ± 4.62%, 98.05 ± 5.61%, 92.20 ± 5.12%, and 89.27 ± 4.74%, at 200 mg L-1 concentration respectively. BPI derivatives displayed perfect DNA cleavage activity and plasmid DNA was completely broken at all tested concentrations. The antimicrobial and antimicrobial photodynamic therapy (APDT) activities of the compounds were investigated and BPI derivatives showed good APDT. E. coli cell viability was inhibited at 125 and 250 mg L-1. BPI-OH, Pt-BPI-OH, Cu-BPI-OH, and Co-BPI-OH also successfully inhibited the biofilm formation of S. aureus and P. aeruginosa. Furthermore, the antidiabetic activity of BPI derivatives was studied. This study also evaluates the binding affinities of four compounds (BPI-OH, Pt-BPI-OH, Cu-BPI-OH, and Co-BPI-OH) to various residues of DNA using hydrogen bond distance measurements and binding energies. The results show that the BPI-OH compound forms hydrogen bonds with residues in the major groove of DNA, while BPI-Pt-OH, BPI-Cu-OH, and BPI-Co-OH compounds form hydrogen bonds with residues in the minor groove. The hydrogen bond distances for each compound range from 1.75 to 2.2 Angstroms.


Assuntos
Anti-Infecciosos , Complexos de Coordenação , Glicerol , Espectroscopia de Infravermelho com Transformada de Fourier , Cobre/química , Escherichia coli , Staphylococcus aureus , Complexos de Coordenação/química , Anti-Infecciosos/química , DNA/metabolismo
4.
Chemosphere ; 339: 139340, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37379977

RESUMO

Antimicrobial resistance to antibiotics for current bacterial infection treatments is a medical problem. 2D nanoparticles, which can be used as both antibiotic carriers and direct antibacterial agents due to their large surface areas and direct contact with the cell membrane, are important alternatives in solving this problem. This study focuses on the effects of a new generation borophene derivative obtained from MgB2 particles on the antimicrobial activity of polyethersulfone membranes. MgB2 nanosheets were created by mechanically separating magnesium diboride (MgB2) particles into layers. The samples were microstructurally characterized using SEM, HR-TEM, and XRD methods. MgB2 nanosheets were screened for various biological activities such as antioxidant, DNA nuclease, antimicrobial, microbial cell viability inhibition, and antibiofilm activities. The antioxidant activity of nanosheets was 75.24 ± 4.15% at 200 mg/L. Plasmid DNA was entirely degraded at 125 and 250 mg/L nanosheet concentrations. MgB2 nanosheets exhibited a potential antimicrobial effect against tested strains. The cell viability inhibitory effect of the MgB2 nanosheets was 99.7 ± 5.78%, 99.89 ± 6.02%, and 100 ± 5.84% at 12.5 mg/L, 25 mg/L, and 50 mg/L, respectively. The antibiofilm activity of MgB2 nanosheets against S. aureus and P. aeruginosa was observed to be satisfactory. Furthermore, a polyethersulfone (PES) membrane was prepared by blending MgB2 nanosheets from 0.5 wt to 2.0 wt %. Pristine PES membrane also has shown the lowest steady-state fluxes at 30.1 ± 2.1 and 56.6 L/m2h for BSA and E. coli, respectively. With the increase of MgB2 nanosheets amount from 0.5 to 2.0 wt%, steady-state fluxes increased from 32.3 ± 2.5 to 42.0 ± 1.0 and from 15.6 ± 0.7 to 24.1 ± 0.8 L/m2h, respectively for BSA and E. coli. E. coli elimination performance of PES membrane coated with MgB2 nanosheets at different rates and the membrane filtration procedure was obtained from 96% to 100%. The results depicted that BSA and E. coli rejection efficiencies of MgB2 nanosheets blended PES membranes increased when compared to pristine PES membranes.


Assuntos
Anti-Infecciosos , Boro , Escherichia coli , Staphylococcus aureus , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Pseudomonas aeruginosa
5.
Anal Bioanal Chem ; 413(4): 1107-1116, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33388846

RESUMO

This paper proposes the use of Anoxybacillus flavithermus SO-15 immobilized on iron oxide nanoparticles (NPs) as a novel magnetized biosorbent for the preconcentrations of uranium (U) and thorium (Th). The SPE procedure was based on biosorption of U(VI) and Th(IV) on a column of iron oxide NPs loaded with dead and dried thermophilic bacterial biomass prior to U(VI) and Th(IV) measurements by ICP-OES. The biosorbent characteristicswere explored using FT-IR, SEM, and EDX. Significant operational factors such as solution pH, volume and flow rate of the sample solution, amounts of dead bacteria and iron oxide nanoparticles, matrix interference effect, eluent type, and repeating use of the biosorbent on process yield were studied. The biosorption capacities were found as 62.7 and 56.4 mg g-1 for U(VI) and Th(IV), respectively. The novel extraction process has been successfullyapplied to the tap, river, and lake water samples for preconcentrations of U(VI) and Th(IV).


Assuntos
Anoxybacillus/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Extração em Fase Sólida/métodos , Tório/isolamento & purificação , Urânio/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Células Imobilizadas/química
6.
Int J Biol Macromol ; 161: 1581-1590, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32777412

RESUMO

In this study, a herbal infused oil (Hypericum perforatum, HP) incorporated chitosan (CS) cryogel as a wound dressing material was produced in order to be used in wound healing process. The main strategy is to combine the traditional perspective of using medicinal oils with polymeric scaffolds manufactured by an engineering approach to fabricate a potential tissue engineering product that provides both new tissue formation and wound healing. The scaffolds manufactured by cryogelation were soft, spongy, highly porous, physically stable, elastic and could be easily cut in any desired shape. Physicochemical, mechanical and morphological analyzes were used to characterize the produced cryogels. Young modulus of the plain chitosan cryogel was about 21 kPa whereas it increased with increasing HP oil content and became 61 kPa for 20% HP oil ratio. Further, the antimicrobial studies, antioxidant and DNA cleavage effects were investigated. Samples including the highest ratio of oil (CS4) showed the highest DPPH scavenging activity as 69.9%. In addition, 20% HP oil loaded chitosan cryogel demonstrated single strain DNA cleavage activitiy at 500 µg/mL concentration. Antimicrobial studies were applied against seven strains. The lowest activities were obtained against E. hirae and B. cereus, the highest against E. coli and L. pneumophila. This study concluded that the newly developed HP oil loaded chitosan cryogel scaffolds with unique antimicrobial and antioxidant properties are promising candidates to be used in tissue engineering applications as wound dressing for exudative and long-term healing wounds.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Bandagens , Quitosana/química , Hypericum/química , Óleos de Plantas/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Materiais Biocompatíveis/química , Fenômenos Químicos , Criogéis/química , Clivagem do DNA/efeitos dos fármacos , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Fenômenos Mecânicos , Espectroscopia de Infravermelho com Transformada de Fourier , Cicatrização/efeitos dos fármacos
7.
Mikrochim Acta ; 186(6): 355, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31098920

RESUMO

The fungus Bovista plumbea immobilized on γ-Fe2O3 nanoparticles is shown to be a novel sorbent for magnetic solid-phase extractions of U(VI) and Th(IV). The biosorbent was characterized by FT-IR, SEM, and EDX. The effects of pH value, flow rate and volume of sample, amounts of biomass and support material, eluent type, foreign ions and repeated use of the sorbent on extraction efficiency were investigated. The sorption capacities are 41 and 44 mg g-1, respectively, for U(VI) and Th(IV). The results indicated that B. plumbea immobilized onto γ-Fe2O3 nanoparticles can be utilized as a novel material for the preconcentrations of U(VI) and Th(IV) in certified materials and in spiked tap, river and lake waters. Graphical abstract Schematic presentation of a method for preconcentrations of Th(IV) and U(VI) ions using γ-Fe2O3 nanoparticles loaded with the fungus Bovista plumbea.


Assuntos
Basidiomycota/química , Poluentes Ambientais/análise , Óxido Ferroso-Férrico/química , Nanopartículas de Magnetita/química , Extração em Fase Sólida , Tório/análise , Urânio/análise , Análise Espectral
8.
Food Chem ; 266: 126-132, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30381167

RESUMO

This study deals with the preconcentrations of Ni(II) and Co(II) ions in real samples using the solid phase extraction method (SPE) before their determinations by inductively coupled plasma optical emission spectrometry (ICP-OES). Thermophilic bacterium Geobacillus stearothermophilus SO-20 (Accession number: KJ095002), loaded with Amberlite XAD-4, was utilized as a novel biosorbent. Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscope (SEM) were employed for the investigation of the bacterial surface before and after Ni(II) and Co(II) biosorption. The experimental parameters were examined to find the best conditions. The retained Ni(II) and Co(II) ions on the biosorbent were eluted by using 5.0 ml of 1.0 mol l-1 HCI as the best eluent. The sorption capacities were found to be 16.8 mg g-1 for Ni(II) and 21.6 mg g-1 for Co(II). It was also successfully used for the quantification of Ni(II) and Co(II) in a river water sample, some vegetables and soil.


Assuntos
Cobre/química , Geobacillus stearothermophilus/química , Níquel/química , Adsorção , Células Imobilizadas/química , Cobre/isolamento & purificação , Água Doce/química , Concentração de Íons de Hidrogênio , Íons/química , Microscopia Eletrônica de Varredura , Níquel/isolamento & purificação , Poliestirenos/química , Polivinil/química , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Biosens Bioelectron ; 111: 10-17, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29631158

RESUMO

Herein, we prepared a novel quartz crystal microbalance (QCM) sensor for synthetic cannabinoids (JWH-073, JWH-073 butanoic acid, JWH-018 and JWH-018 pentanoic acid,) detection. Firstly, the synthetic cannabinoid (SCs) imprinted (MIP) and non-imprinted (NIP) nanoparticles were synthesized by mini-emulsion polymerization system. The SCs-imprinted nanoparticles were first characterized by SEM, TEM, zeta-size and FTIR-ATR analysis and then were dropped onto the gold QCM surface. The SCs-imprinted QCM sensor was characterized by an ellipsometer, contact angle, and AFM. The limit of detection was found as 0.3, 0.45, 0.4, 0.2 pg/mL JWH-018, JWH-073, JWH-018 pentanoic acid and JWH-073 butanoic acid, respectively. The selectivity of the SCs-imprinted QCM sensor was shown by using JWH-018, JWH-018 pentanoic acid, JWH-073 and JWH-073 butanoic acid. According to the results, the SCs-imprinted QCM sensors show highly selective and sensitive in a broad range of synthetic cannabinoid concentrations (0.0005-1.0 ng/mL) in both aqueous and synthetic urine solutions.


Assuntos
Canabinoides/urina , Drogas Ilícitas/urina , Indóis/urina , Impressão Molecular/métodos , Naftalenos/urina , Polímeros/química , Técnicas de Microbalança de Cristal de Quartzo/métodos , Humanos , Limite de Detecção , Nanopartículas/química , Detecção do Abuso de Substâncias/métodos , Propriedades de Superfície
10.
Artif Cells Nanomed Biotechnol ; 44(5): 1276-84, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25811997

RESUMO

The covalent immobilization of Trichoderma reesei cellulase onto modified ReliZyme HA403 and Sepabeads EC-EP supports were carried out. The optimal immobilization conditions were determined using response surface methodology. The hydrolysis of cellulose using the free and immobilized cellulase preparations in ionic liquids (IL) using cosolvents was investigated. The hydrolytic activities in buffer medium containing 25% (v/v) of 1-butyl-3-methylimidazolium hexafluorophosphate were around 2.6-, 1.6-, and 5.5-fold higher than the activities in buffer medium. The retained initial activities were 32% and 57%, respectively for cellulase preparations immobilized onto Sepabeads EC-EP support and onto modified ReliZyme HA403 support after 5 reuses.


Assuntos
Celulase/química , Celulose/química , Proteínas Fúngicas/química , Trichoderma/enzimologia , Enzimas Imobilizadas/química , Hidrólise
11.
Int J Radiat Biol ; 90(1): 95-103, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23952340

RESUMO

PURPOSE: Many strategies have been investigated to exclude the several side-effects of pharmacological or invasive treatments. Non-invasive pulsed magnetic field (PMF) treatment with no toxicity or side-effects can be an alternative to pharmacologic treatments. The purpose of this study was, therefore, to investigate the pain-relieving effects of PMF treatment in the inflammatory pain conditions. MATERIALS AND METHODS: Effects of PMF treatment on the hallmarks of the inflammatory pain indices such as hyperalgesia, allodynia, edema and several biochemical parameters that evaluate oxidative stress were investigated using a well established carrageenan (CAR)-induced hindpaw inflammation model in rats. RESULTS: CAR injection lowered the paw withdrawal thermal latencies (hyperalgesia) and mechanical thresholds (allodynia). CAR also decreased the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) levels and increased malondialdehyde (MDA) levels compared with healthy rat paw tissues. PMF treatment produced significant increases in the thermal latencies and mechanical thresholds in CAR-injected paws. In the inflamed paw tissues, PMF increased the activities of SOD, CAT and GPx and decreased MDA level. We also demonstrated that PMF decreased paw mass indicating that it has an anti-edematous potential. CONCLUSIONS: The present results reveal that PMF treatment can ameliorate the CAR-induced inflammatory pain indices such as mechanical allodynia, thermal hyperalgesia and edema, and attenuate the oxidative stress. The action mechanisms of PMF in CAR-induced inflammation might be related to the increases in the levels of antioxidant enzymes in inflamed tissues. The findings suggest that PMF treatment might be beneficial in inflammatory pain conditions.


Assuntos
Hiperalgesia/prevenção & controle , Inflamação/prevenção & controle , Magnetoterapia/métodos , Animais , Carragenina , Modelos Animais de Doenças , Feminino , Humanos , Hiperalgesia/induzido quimicamente , Inflamação/induzido quimicamente , Ratos , Ratos Wistar , Resultado do Tratamento
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