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1.
Ecotoxicol Environ Saf ; 269: 115801, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38064791

RESUMO

In the present day, the widespread presence of lingering contaminants in ecosystems has prompted scientists to develop novel semiconductor nanoarchitectures that assist in photocatalytic reactions mediated by visible light. As a result, we propose to prepare a series of Dy-Mn-O based nano-catalysts using a sonochemical approach utilizing various ionic phases of surfactants as structure-directing agents. In this study, X-ray diffraction (XRD) and Rietveld refinement techniques were used to explore the fundamental effects of surfactants on the compositional-structural features of the materials. In terms of morphological profiles, DyMnO3/Dy2O3 (DM) nanostructures fabricated with Triton X-80 as a structure-directing agent showed the best uniformity with an acceptable size range between 14.14 and 52.35 nm. In the visible-light-driven photocatalytic domain, these nanocomposites provide high responsiveness based on their optical band gap value of 2.0 eV. According to our findings, two individual factors affect dye activity, namely dye type and concentration, which is why a high decomposition efficiency of 78.8% was obtained for 10 ppm Acid violet (AV) using DyMnO3/Dy2O3 nanocomposites after 120 min of exposure to visible light. Furthermore, radical quenching test confirmation confirmed the mechanistic behind the degradation process. This indicates that active species of O2•- and •OH may play a significant role in photocatalysis. As a result of repeated processes over three consecutive cycles, binary DyMnO3/Dy2O3 nanocomposites had an efficiency of 64.4% in removing dyes from the environment, indicating their high stability.


Assuntos
Ecossistema , Nanocompostos , Luz , Nanocompostos/química , Tensoativos , Catálise
2.
Ecotoxicol Environ Saf ; 266: 115578, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37856984

RESUMO

In this study, a green approach was used to synthesize SmMnO3 magnetic nanoparticles via the auto combustion method, where pomegranate juice was utilized as a natural fuel. The concentration of fuel was varied to investigate its effect on the purity and morphology of SmMnO3 nanoparticles. The physiochemical properties of the synthesized nanoparticles, including crystal structures, morphology, optical, and magnetic properties, were investigated using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier-Transform Infrared Spectroscopy (FTIR), Vibrating Sample Magnetometer (VSM), Diffuse Reflectance Spectroscopy (DRS), X-ray fluorescence (XRF) and Brunauer-Emmett-Teller (BET). The band gap of the as-synthesized nanoparticles was determined to be 1.8 eV, indicating their potential as a photocatalyst. The photocatalytic activity of SmMnO3 nanoparticles was evaluated against Methyl violet and Erythrosine, and the mechanism of photocatalyst was determined using EDTA, benzoic acid, and benzoquinone as scavengers. Photocatalytic activity was studied in both UV and visible light, and it was found that the maximum degradation (94%) was related to the degradation of Erythrosine (10 ppm) in the presence of visible light. The stability test of SmMnO3 performed and confirmed the stability of nanoparticles after 5 cycles. The results suggest that SmMnO3 nanoparticles synthesized via the green auto combustion method using pomegranate juice as a natural fuel can serve as a promising photocatalyst for the degradation of organic pollutants in the environment. Further studies can be conducted to investigate their potential in other applications.


Assuntos
Poluentes Ambientais , Nanopartículas , Poluentes da Água , Samário , Eritrosina , Luz , Água , Catálise
3.
Inorg Chem ; 61(18): 6750-6763, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35465668

RESUMO

Owing to the extensive requirement for renewable energy sources such as hydrogen, great efforts are being devoted to optimizing the active ingredients for advanced hydrogen storage. In this regard, an ideal spinel-perovskite nanocomposite based on Li-Mn-Fe-Si materials was successfully fabricated via a one-pot hydrothermal route to store hydrogen electrochemically. To optimize both the phase composition and morphological features of nanostructures, the reaction was engineered under different conditions. Li-Mn-Fe-Si spinel-perovskite diphase structures were created with diverse shapes of polyhedral-shaped bulk particles, nanoparticles, nanoplates, and hierarchical structures. The alteration of multiple factors such as hydrothermal reaction time, temperature, polymeric surfactant type, and calcination temperature was surveyed to achieve the optimized size and morphology of the nanoproducts to be obtained. The morphological changes, structural regulations, porosity, and magnetic properties of the nanosized products were studied via field-emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray powder diffraction (XRD), Raman spectroscopy, Brunauer-Emmett-Teller (BET), and vibrating sample magnetometer (VSM) analyses. In addition, the electrochemistry features of the Li0.66Mn1.85Fe0.43O4/Fe2.57Si0.43O4/FeSiO3 (LMFO/FSO) nanocomposites were introduced on the basis of discharge capacity, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry(CV) methods in an alkaline electrolyte. The discharge capacity of the LMFO/FSO nanostructures with a nanoplate-like morphology as an optimal sample was calculated to be 910 mAh/g after 15 cycles at a constant current of 1 mA. The electrochemistry results confirm that the hydrogen storage capability of nanoplate composites is higher than those of other morphologies due to their superior surface area and faster electron transfer. Besides, this proposed strategy could simultaneously manipulate the architectural and compositional complexities to generate a superior electrochemical behavior in energy storage devices.

4.
Ecotoxicol Environ Saf ; 208: 111712, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396043

RESUMO

The photocatalytic process is an environmentally-friendly procedure that has been well known in the destruction of organic pollutants in water. The multiple semiconductor heterojunctions are broadly applied to enhance the photocatalytic performances in comparison to the single semiconductor. Polymeric semiconductors have received much attention as inspiring candidates owing to their adjustable optical absorption features and simply adaptable electronic structure. The shortcomings of the current photocatalytic system, which restricts their technical applications incorporate fast charge recombination, low-utilization of visible radiation, and low immigration capability of the photo-induced electron-hole. This paper indicates the novel fabrication of new CuI/g-C3N4 nanocomposite by hydrothermal and ultrasound-assisted co-precipitation methods. The structure, shape, and purity of the products were affected by different weight percentages and fabrication processes. Electron microscope unveils that CuI nanoparticles are distributed on g-C3N4. The bandgap of pure carbon nitride is estimated at 2.70 eV, and the bandgap of the nanocomposite has increased to 2.8 eV via expanding the amount of CuI. The CuI/C3N4 nanocomposite has a great potential to degrade cationic and anionic dyes in high value because of its appropriate bandgap. It can be a great catalyst for water purification. The photocatalytic efficiency is affected by multiple factors such as types of dyes, fabrication methods, the light sources, mass ratios, and scavengers. The fabricated CuI/C3N4 nanocomposite exposes higher photocatalytic performance than the pure C3N4 and CuI. The photocatalytic efficiency of nanocomposite is enhanced by enhancing the amount of CuI. Besides, the fabricated CuI/C3N4 revealed remarkable reusability without the obvious loss of photocatalytic activity. The antibacterial activity of the specimens reveals that the highest antimicrobial activities are revealed against P. aeruginosa and E. coli. These results prove that the nanocomposite possesses high potential for killing bacteria, and it can be nominated as a suitable agent against bacteria.


Assuntos
Antibacterianos/farmacologia , Cobre/química , Grafite/química , Iodetos/química , Compostos de Nitrogênio/química , Poluentes Químicos da Água/isolamento & purificação , Antibacterianos/química , Catálise , Corantes/química , Corantes/isolamento & purificação , Corantes/metabolismo , Cobre/farmacologia , Grafite/farmacologia , Iodetos/farmacologia , Luz , Nanocompostos/química , Compostos de Nitrogênio/farmacologia , Poluentes Químicos da Água/química , Purificação da Água/métodos
5.
J Am Chem Soc ; 142(26): 11428-11433, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32391696

RESUMO

The employment of 2D perovskites is a promising approach to tackling the stability and voltage issues inherent in perovskite solar cells. It remains unclear, however, whether other perovskites with different dimensionalities have the same effect on efficiency and stability. Here, we report the use of quasi-3D azetidinium lead iodide (AzPbI3) as a secondary layer on top of the primary 3D perovskite film that results in significant improvements in the photovoltaic parameters. Remarkably, the utilization of AzPbI3 leads to a new passivation mechanism due to the presence of surface dipoles resulting in a power conversion efficiency (PCE) of 22.4%. The open-circuit voltage obtained is as high as 1.18 V, which is among the highest reported to date for single junction perovskite solar cells, corresponding to a voltage deficit of 0.37 V for a band gap of 1.55 eV.

6.
J Environ Manage ; 230: 266-281, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30292015

RESUMO

Neodymium Vanadate (NdVO4) nanostructures were successfully synthesized via a modified solid state method in the presence of ligand. These nanoparticles were further used as a photocatalyst. Primarily the best structural formations and smallest crystallite sizes of the systems were identified and optimized by changing the calcination time, calcination temperature and molar ratio of the ligand. The cationic (Methyl Violet (MV)), and anionic (Eosin Y (EY) and Eriochrome Black T (EBT)) dyes were used as a model to evaluate the photoactivity under UV-Vis irradiation. Several operational factors were examined to improve the photocatalytic efficiency include type of dye, type of light source, pH and dye concentration. As a result, the best efficiency in 5 ppm Eriochorome Black T at pH = 11 was achieved in the presence of 0.05 g NdVO4 nanocatalysts.


Assuntos
Nanopartículas/química , Neodímio/química , Vanadatos/química , Purificação da Água/métodos , Catálise , Corantes/química , Nanoestruturas/química , Processos Fotoquímicos
7.
J Environ Manage ; 233: 107-119, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30576958

RESUMO

A simple and clean synthesis for Nd2Sn2O7-SnO2 nanocomposites as high-efficiency visible-light responsive photocatalyst is described applying extract of pineapple, for the first time. As novel and non-toxic biofuel, extract of pineapple, is employed to fabricate Nd2Sn2O7-SnO2 nanocomposites through an environment-friendly procedure. The findings denote that the applied biofuel can play a meaningful role as capping agent during preparation of Nd2Sn2O7-SnO2 nanocomposites. Depending on the applied dosage of pineapple extract as well as time for fabrication, the grain size, photocatalytic yield and morphology of Nd2Sn2O7-SnO2 structures changed. A suite of identification methods like XRD, TEM, EDS, DRS, BET and FESEM are utilized for investigation of the produced Nd2Sn2O7-SnO2 nanocomposites. Nd2Sn2O7-SnO2 structures are utilized as visible-light responsive photocatalyst to degrade the rhodamine B and eosin Y contaminants. The produced Nd2Sn2O7-SnO2 nanocomposites have been found to be very effective as visible-light responsive photocatalyst to degrade contaminants which may bring to environmental pollution.


Assuntos
Poluentes Ambientais , Água , Catálise , Fotólise , Compostos de Estanho
8.
Inorg Chem ; 57(18): 11443-11455, 2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30160103

RESUMO

In the present study, Tl4CdI6 nanostructures were synthesized via a facile sonochemical method. The effect of molar ratio of TlI to CdI2, reaction time, power of sonication, and the capping agents was investigated on morphology, size, and purity of the products. The as-prepared nanomaterials were characterized by X-ray diffraction, X-ray energy dispersive spectroscopy, field emission scanning, transmission electron microscopy, and Raman spectroscopy. The optical property of Tl4CdI6 nanoparticles was investigated by ultraviolet-visible spectroscopy (UV-vis), and the band gap was estimated about 2.82 eV. The photocatalytic behaviors of the nanoparticles were investigated by removal and degradation of different organic dyes under the UV irradiation. The results indicated a highest degradation for acid black 1 of 85.7% in 110 min. This sample was selected as an optimum sample for photocatalytic application.

9.
Nanotechnology ; 29(7): 075404, 2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29244654

RESUMO

A new method for the deposition of a pinhole-free compact layer of TiO2 is introduced for the development of efficient perovskite solar cells. Acidic treatment of titanium layer (ATTL), deposited by rotational magnetron sputtering, presents a compact pinhole-free TiO2 thin film. Deposition of a compact TiO2 thin film on fluorine-doped tin oxide layers by ATTL did not change the surface roughness. To compare the introduced method, perovskite solar cell devices were fabricated and studied using different methods for the deposition of the TiO2 compact layers, which were used as common compact layer deposition methods. The ATTL method proposed considerable photovoltaic enhancement of perovskite solar cell performance (at least 22% enhancement in this work) by reducing the pinholes and sheet resistance of the TiO2 thin film. The improvement in the open-circuit voltage and the fill factor of the prepared devices using the ATTL method strongly confirmed the nature of the deposited pinhole-free TiO2 thin film. This method is shown to be an appropriate route for the reliable large-scale deposition of TiO2 compact layers.

10.
Luminescence ; 29(8): 1074-81, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24723462

RESUMO

We report the first detailed study of the characteristics of an octahydro-Schiff base derivative as a new luminophor in the peroxyoxalate chemiluminescence (POCL) system. The effect of reagents on this new POCL system was investigated. In addition, the response surface methodology was used for evaluating the relative significance of variables in this POCL system, establishing models and determining optimal conditions. The quenching effect of some cations and compounds such as Cu(2+), Fe(3+), Hg(2+), imidazole, histidine and cholesterol on an optimized POCL reaction were studied. The dynamic ranges were up to approximaterly 100 and 175 × 10(-6) M for Cu(2+) and cholesterol respectively. The detection limits were 3.3 × 10(-6) m and 2.58 × 10(-6) m for Cu(2+) and histidine, respectively. In all cases the relative standard deviations were 4-5% (n = 4).


Assuntos
Colesterol/química , Luminescência , Medições Luminescentes/métodos , Oxalatos/química , Aminoácidos/química , Cátions/análise , Cátions/química , Colesterol/análise , Cobre/química , Histidina/análise , Histidina/química , Imidazóis/análise , Imidazóis/química , Ferro/química , Limite de Detecção , Bases de Schiff/química , Sensibilidade e Especificidade
11.
Eur J Med Res ; 29(1): 224, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594732

RESUMO

The latest findings in iron metabolism and the newly uncovered process of ferroptosis have paved the way for new potential strategies in anti-leukemia treatments. In the current project, we reviewed and summarized the current role of nanomedicine in the treatment and diagnosis of leukemia through a comparison made between traditional approaches applied in the treatment and diagnosis of leukemia via the existing investigations about the ferroptosis molecular mechanisms involved in various anti-tumor treatments. The application of nanotechnology and other novel technologies may provide a new direction in ferroptosis-driven leukemia therapies. The article explores the potential of targeting ferroptosis, a new form of regulated cell death, as a new therapeutic strategy for leukemia. It discusses the mechanisms of ferroptosis and its role in leukemia and how nanotechnology can enhance the delivery and efficacy of ferroptosis-inducing agents. The article not only highlights the promise of ferroptosis-targeted therapies and nanotechnology in revolutionizing leukemia treatment, but also calls for further research to overcome challenges and fully realize the clinical potential of this innovative approach. Finally, it discusses the challenges and opportunities in clinical applications of ferroptosis.


Assuntos
Ferroptose , Leucemia , Humanos , Nanotecnologia , Leucemia/tratamento farmacológico
12.
Environ Sci Pollut Res Int ; 31(14): 21370-21379, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38388980

RESUMO

In this article, we present the synthesis of binary CdAl4O7/CdO nanocomposites using green tea extracts and green chemistry methods for high-performance hydrogen storage. The green tea extract contains bioactive compounds (polyphenols) that act as reducing agents, which facilitate the reaction between metal ions and water. By examining the structural and morphological characteristics of the obtained substrates using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR), it was demonstrated that the nanocomposites were successfully synthesized. We evaluated the electrochemical performance of the synthesized CdAl4O7/CdO nanocomposites using a three-electrode chronopotentiometry system. According to the results, the synthesized nanocomposites are capable of storing 1750 mAh/g of hydrogen at a constant current of 1 Amp. By using green tea extract as a natural structure-directing agent, the CdAl4O7/CdO nanocomposite can be developed more sustainably as high-performance hydrogen storage materials. Ultimately, this work contributes to the advancement of sustainable energy storage through the synthesis of a promising new material.


Assuntos
Hidrogênio , Nanocompostos , Espectroscopia de Infravermelho com Transformada de Fourier , Nanocompostos/química , Difração de Raios X , Chá/química
13.
Adv Colloid Interface Sci ; 329: 103204, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797070

RESUMO

Theranostic nanoparticles (NPs) have the potential to dramatically improve cancer management by providing personalized medicine. Inorganic NPs have attracted widespread interest from academic and industrial communities because of their unique physicochemical properties (including magnetic, thermal, and catalytic performance) and excellent functions with functional surface modifications or component dopants (e.g., imaging and controlled release of drugs). To date, only a restricted number of inorganic NPs are deciphered into clinical practice. This review highlights the recent advances of inorganic NPs in breast cancer therapy. We believe that this review can provides various approaches for investigating and developing inorganic NPs as promising compounds in the future prospects of applications in breast cancer treatment and material science.


Assuntos
Antineoplásicos , Neoplasias da Mama , Nanopartículas , Nanomedicina Teranóstica , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Nanopartículas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Animais , Medicina de Precisão
14.
Environ Sci Pollut Res Int ; 31(17): 24768-24787, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38523214

RESUMO

An alternative method to conventional synthesis is examined in this review by the use of plant extracts as reducing and capping agents. The use of plant extracts represents an economically viable and environmentally friendly alternative to conventional synthesis. In contrast to previous reviews, this review focuses on the synthesis of nano-compounds utilizing plant extracts, which lack comprehensive reports. In order to synthesize diverse nanostructures, researchers have discovered a sustainable and cost-effective method of harnessing functional groups in plant extracts. Each plant extract is discussed in detail, along with its potential applications, demonstrating the remarkable morphological diversity achieved by using these green synthesis approaches. A reduction and capping agent made from plant extracts is aligned with the principles of green chemistry and offers economic advantages as well as paving the way for industrial applications. In this review, it is discussed the significance of using plant extracts to synthesize nano-compounds, emphasizing their potential to shape the future of nanomaterials in a sustainable and ecologically friendly manner.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Nanopartículas Metálicas/química , Extratos Vegetais/química , Química Verde , Nanoestruturas/química , Plantas/química , Antibacterianos
15.
Chemosphere ; 338: 139564, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37467852

RESUMO

In recent years, water contamination has become a significant crisis, and it is crucial to find new materials that can efficiently eliminate these contaminants. The current work presents the Sm2CuO4 nanophotocatalyst for the decolorization of different water-soluble organic contaminants. The fabrication of Sm2CuO4 nanostructures was achieved using a simple and rapid sonochemical pathway, resulting in an optical bandgap of 1.62 eV as determined by diffuse reflectance spectroscopy. Several factors, including different organic contaminants, organic contaminant concentrations, Sm2CuO4 dosages, and the pH of the media, were scrutinized to achieve the best efficiency. The results manifested that Sm2CuO4 was highly effective in removing different organic contaminants from water. For example, when 30 mg of Sm2CuO4 was used with 20 mg L-1 methyl orange under visible irradiation for 100 min, 91.4% of the methyl orange was destroyed. Further investigation revealed that holes (h+) were primarily responsible for pollutant photodegradation when using Sm2CuO4 as a photocatalyst. This finding suggests that Sm2CuO4 could be an excellent candidate for developing new materials to effectively remove water contaminants.


Assuntos
Poluentes Ambientais , Nanoestruturas , Poluentes Químicos da Água , Poluentes da Água , Poluentes Químicos da Água/química , Nanoestruturas/química , Água , Catálise
17.
J Mech Behav Biomed Mater ; 148: 106155, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37852085

RESUMO

OBJECTIVES: This study aimed to synthesize and characterize an environmentally friendly nanohydroxyapatite (n-HA) and evaluate its impact on enamel mineral content when incorporated into a Pistachio oleo gum resin (Saqqez) bio-chewing gum for in-situ models. We compared the effects of this green nano-hydroxyapatite (G n-HA) with those of a commercially available synthetic nano-hydroxyapatite (S n-HA). METHODS: Various analytical techniques were employed including XRD, FESEM, FT-IR, EDX/SEM and TGA/DTA to characterize the crystallinity, size and composition of the G n-HA powder. Three chewing gum groups were formulated: (1) Saqqez gum containing 10% wt G n-HA, (2) Saqqez gum containing 10% wt S n-HA, and (3) pure Saqqez gum. In order to evaluate the impact of these chewing gums on enamel, intraoral appliances were fabricated, each containing six enamel specimens. Participants were instructed to chew the gums while wearing these appliances. The calcium (Ca+2) and phosphorus (P) levels in enamel specimens, both with and without exposure to an acid challenge, were quantified using EDX/SEM. FE-SEM was employed to capture the microstructure of the enamel surface. In terms of the statistical analysis, one-way ANOVA and Tukey's post hoc tests were utilized to compare the data, where the significance level (α) was set at 0.05. RESULTS: The characterization tests confirmed the successful synthesis of G n-HA. Furthermore, EDX/SEM analysis of the enamel specimens from the intraoral appliance revealed significant variations in calcium (Ca+2) content among the enamel specimens (P = 0.000). The S n-HA group, in particular, exhibited the highest Ca+2 content, while the pure Saqqez group displayed the lowest. Nonetheless, there was no statistically significant differences in phosphorus (P) content observed among the three groups (P = 0.27). CONCLUSIONS: Saqqez gum can be considered a wholesome natural chewing gum that serves, as a carrier for delivering remineralization agents to the tooth surfaces. This was evident in the groups containing n-HA, exhibiting elevated Ca+2 levels. It's noteworthy that G n-HA demonstrated less efficacy in enamel remineralization compared to S n-HA.


Assuntos
Pistacia , Humanos , Cálcio , Goma de Mascar , Durapatita , Fósforo , Método Simples-Cego , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Ultrason Sonochem ; 95: 106362, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36907102

RESUMO

Thulium vanadate (TmVO4) nanorods were successfully prepared by a simple sonochemical approach using Schiff-base ligands. Additionally, TmVO4 nanorods were employed as a photocatalyst. The most optimal crystal structure and morphology of TmVO4 have been determined and optimized by varying Schiff-base ligands, the molar ratio of H2Salen, the sonication time and power, and the calcination time. A Eriochrome Black T (EBT) analysis revealed that the specific surface area was 24.91 m2/g. A bandgap of 2.3 eV was determined by diffuse reflectance spectroscopy (DRS) spectroscopy, which makes this compound suitable for visible photocatalytic applications. In order to assess the photocatalytic performance under visible light, two anionic dyes (EBT) and cationic dyes (Methyl Violet (MV)) were used as models. A variety of factors have been studied in order to improve the efficiency of the photocatalytic reaction, including dye type, pH, dye concentration, and catalyst loading. Under visible light, the highest efficiency was achieved (97.7%) when 45 mg TmVO4 nanocatalysts were present in 10 ppm Eriochorome Black T at pH = 10.

19.
Int J Biol Macromol ; 253(Pt 8): 127583, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37866577

RESUMO

Modification surface of chitosan nanoparticles using ZnO nanoparticles is important interest in drug delivery because of the beneficial properties. In this study, we proposed a chitosan/ZnO nanocomposite for the targeted delivery of antibacterial peptide (LL37). Synthesized LL37-loaded chitosan/ZnO nanocomposite (CS/ZnO/LL37-NCs) was based on the ionotropic gelation method. The antibacterial activity of the synthesized platform versus Methicillin-resistant Staphylococcus aureus (MRSA) was determined by the microdilution method in 10 mM sodium phosphate buffer. The biofilm formation inhibitory was also evaluated using microtiter plate method. In addition, the ability of CS/ZnO/LL37-NCs on the icaA gene expression level was assessed by the Real-Time PCR. The loading and release investigations confirmed the suitability of CS/ZnO-NCs for LL37 encapsulation. Results showed 6 log10 CFU/ml reduction in MRSA treated with the CS/ZnO/LL37-NPs. Moreover, CS/ZnO/LL37-NCs showed 81 % biofilm formation inhibition than LL37 alone. Also, icaA gene expression decreased 1-fold in the face of CS/ZnO/LL37-NCs. In conclusion, the modification surface of chitosan nanoparticles with ZnO nanoparticles is a suitable chemical platform for the delivery of LL37 that could be used as a promising nanocarrier for enhancing the delivery of antibacterial peptide and improving the antibacterial activity of LL37.


Assuntos
Quitosana , Staphylococcus aureus Resistente à Meticilina , Nanocompostos , Óxido de Zinco , Quitosana/química , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Antibacterianos/farmacologia , Antibacterianos/química , Nanocompostos/química , Biofilmes , Peptídeos/farmacologia , Testes de Sensibilidade Microbiana
20.
Luminescence ; 27(5): 341-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22371380

RESUMO

Fluorescence study of the complexation between uranyl salophen (L) and some common anions in acetonitrile-water (90:10, v/v) solution showed a tendency of L toward acetate ion (AcO-). The fluorescence enhancement of L is attributed to a 1:1 complex formation between L and acetate ion which was utilized as the basis for the selective detection of AcO-. The association constant of the 1:1 complex formation of L-AcO- was calculated as 6.60 × 10(6) . The linear response range of the fluorescent chemosensor covers a AcO- concentration range of 1.6 × 10(-7) to 2.5 × 10(-5) mol/L, with a detection limit of 2.5 × 10(-8) mol/L. L showed a selective and sensitive fluorescence enhancement response toward acetate ion over I3- , NO3-, CN-, CO3 (2-), Br-, Cl-, F-, H2 PO4- and SO4 (2-) , which was attributed to the higher stability of inorganic complex between acetate and L.


Assuntos
Acetatos/química , Íons/química , Medições Luminescentes/métodos , Compostos Organometálicos/química , Fluorescência , Cinética , Limite de Detecção
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