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1.
Anal Bioanal Chem ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39164506

RESUMO

Sample preparation in an analytical sequence increases the number of errors, is highly time-consuming, and involves the manipulation of hazardous reagents. Therefore, when an improvement in an analytical method is required, the sample preparation step needs to be optimised or redesigned. Moreover, this step can involve significant toxic reagents and a high volume of waste. In that regard, this study proposes a new procedure based on microwave-assisted wet digestion combining two green strategies: a miniaturised system (with a few microlitres of volume) and the only use of hydrogen peroxide. Three biological samples (human serum, urine, and plant in vitro material) were chosen due to their high potential for disease monitoring, toxicological studies, and biotechnology applications. Several trace elements (Ca, Cd, Co, Cu, Fe, Mg, Mn, Mo, Ni, Se, and Zn) were determined by inductively coupled plasma optical emission spectroscopy and inductively coupled plasma mass spectrometry. For human serum and urine, a certified reference material was used to check for accuracy; the recovery ranged from 72% (Cd, ICP-MS) to 105% (Mg, ICP OES) for serum, while for urine, they varied from 82% (Ni, ICP-MS) to 122% (Zn, ICP-MS). For the soybean callus sample (in vitro plant material), a comparison between the proposed method and the acid digestion method was conducted to evaluate the accuracy, and the results agreed. The detection limits were 0.001-60 µg L-1 (lowest for Cd), thus demonstrating a suitable sensitivity. Moreover, the decomposition efficiency was demonstrated by determining the residual carbon, and a low amount was found in the final product digested (below 0.8% w v-1). A green metric approach was calculated for the proposed method, and according to AGREEprep software, it was found to be around 0.4. Finally, the method was applied to urine samples collected in patients with COVID-19 and soybean callus cultivated with silver nanoparticles. This sample preparation method is a new acidless and miniaturised alternative for elemental analysis involving biological samples.

2.
Luminescence ; 39(8): e4844, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39103209

RESUMO

This study presents a novel approach for the fabrication of a Co,Ni/MoS2-derived nanohybrid material using wheat straw extract. The facile synthesis method involves a sol-gel process, followed by calcination, showcasing the potential of agricultural waste as a sustainable reducing and chelating reagent. The as-prepared nanohybrid has been characterized using different techniques to analyse its physicochemical properties. X-ray diffraction analysis confirmed the successful synthesis of the nanohybrid material, identifying the presence of NiMoO4, CoSO4 and Mo17O47 as its components. Fourier-transform infrared spectroscopy differentiated the functional groups present in the wheat straw biomass and those in the nanohybrid material, highlighting the formation of metal-oxide and sulphide bonds. Scanning electron microscopy revealed a heterogeneous morphology with agglomerated structures and a grain size of around 70 nm in the nanohybrid. Energy-dispersive X-ray spectroscopy analysis shows the composition of elements with weight percentages of (Mo) 9.17%, (S) 6.21%, (Co) 12.48%, (Ni) 12.18% and (O) 50.46% contributing to its composition. Electrochemical analysis performed through cyclic voltammetry showcased the exceptional performance of the nanohybrid material as compared with MoS2, suggesting its possible applications for designing biosensors and related technologies. Thus, the research study presented herein underscores the efficient utilization of natural resources for the development of functional nanomaterials with promising applications in various fields. This study paves a way for manufacturing innovation along with advancement of novel synthesis method for sustainable nanomaterial for future technological developments.


Assuntos
Cobalto , Dissulfetos , Molibdênio , Níquel , Triticum , Triticum/química , Molibdênio/química , Dissulfetos/química , Níquel/química , Cobalto/química , Extratos Vegetais/química , Tamanho da Partícula , Propriedades de Superfície
3.
Mikrochim Acta ; 191(3): 150, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386132

RESUMO

The modification of graphite screen-printed electrodes (SPEs) is reported using an eco-friendly and extremely fast method based on the direct cobalt pin electrode-to-SPE spark discharge at ambient conditions. This approach does not utilize any liquids or chemical templates, does not produce any waste, and allows the in-situ generation of CoxOy nanoparticles onto the electrode surface and the development of efficient electrocatalytic sensing surfaces for the determination of H2O2. Co-spark SPEs were characterized using scanning electron microscopy, energy-dispersive X-ray spectroscopy and x-ray photoelectron spectroscopy (XPS), revealing the formation of surface confined CoxOy nanoparticles and the diverse oxidation states of cobalt species. Co-spark SPEs were also characterized with cyclic voltammetry and electrochemical impedance spectroscopy. Redox transitions of the surface confined electrocatalysts are demonstrated by electrochemical polarization studies, showing the formation of different oxides (CoxOy), varying the XPS results. Amperometric measurements at 0.3 V vs. Ag/AgCl revealed a linear relationship between the current response and the concentration of H2O2 over the range 1 - 102 µM, achieving a limit of detection (3σ/m) of 0.6 µM. The interference effect of various electroactive species was effectively addressed by employing dual measurements in the absence and presence of the enzyme catalase. The analytical utility of the method was evaluated in antioxidant rich real-world samples, such as energy drinks, demonstrating sufficient recovery.

4.
Environ Res ; 235: 116703, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37474089

RESUMO

Based on a green approach, the potential use of waste tea biomass (fiber and second sieving) with rich polyphenol content was investigated as an alternative source of polyphenol to achieve an economic added value. In addition, this study demonstrated a comparative approach to explore the most sustainable green extraction method by the assessment of single ultrasound-assisted extraction (UAE) at various frequencies (20, 35, and 200 kHz) and the hybrid operations of ultrasound (US) and thermal extraction (50 °C and 80 °C). As a result, it has been determined that waste tea biomass, with a polyphenol extraction rate of more than 80%, provides a higher recovery capacity than tea leaf (the highest polyphenol recovery rate of 72.5%) in almost all single operations. Among the single UAE, 20 kHz was expressed as the method succeeding with high recovery rates (84%) within 30 min for fiber waste. In contrast, the hybrid operation consisting of 20 kHz US (20 min) with heating at 80 °C (10 min) yielded the highest extraction efficiency with 92% in the same time interval more economically for second sieving waste tea biomass. Therefore, this study has shown that it is possible to utilize UAE alone or in combination with heat extraction from tea waste for environmentally friendly, rapid, and effective polyphenol extraction.


Assuntos
Polifenóis , Chá , Biomassa , Extratos Vegetais , Temperatura Alta
5.
AAPS PharmSciTech ; 24(5): 127, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37264247

RESUMO

Mosapride citrate (MC) is a poorly soluble short half-life drug with more pronounced absorption in the stomach. The present study aimed to incorporate MC co-crystals with enhanced solubility into 3D-printed floating tablets. MC co-crystals were prepared via the green method using Saccharin sod. as a co-former at a (1:1) molar ratio. The prepared co-crystals were assessed for solubility, FTIR, thermal behavior, and SEM. Then, it was incorporated into zero % infill 3D-printed tablets of different configurations at two thickness levels by the FDM printing technique. Printed tablets were evaluated for dimensions, weight deviation, friability, and in vitro floating behavior. Drug release and kinetic of the MC release were also assessed. Solubility study of the co-crystals showed a significant (p value < 0.05) increased solubility over pure MC. FTIR and thermal behavior confirmed hydrogen bonding formation during co-crystallization. The obstructed particles had an erratic protrusion form, similar to a nodule, as illustrated by SEM. The printed tablets showed acceptable physicochemical properties. Tablets floated for about ≥ 12 h without floating lag time. In vitro drug release exhibited variable extended release profiles with different lag times depending on the configuration indicating that the tablet's wall thickness and surface area were the factors manipulated to control drug release. Kinetic analysis of the release data displayed intermediate kinetics between zero-order and diffusional kinetics. The intragastric extended release profile for MC co-crystals of improved solubility could be successfully, economically, and quickly developed utilizing the 3D printing technique.


Assuntos
Impressão Tridimensional , Sacarina , Cinética , Comprimidos/química , Liberação Controlada de Fármacos , Solubilidade , Tecnologia Farmacêutica/métodos
6.
Environ Res ; 209: 112750, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35090872

RESUMO

Herein, we report a Ceria-graphitic oxide sheets (CeO2-GOS) nanocomposites photo catalyst synthesized by simple and green methods for the degradation of textile effluents and dyes. In the first step, green treated CeO2 NPs were synthesized through a simple organic reduction method. Further, green synthesized CeO2 NPs were anchored with GOS to produce CeO2-GOS nanocomposites by a sol-gel method. The phase morphology and structure of CeO2-GOS nanocomposites was systematically characterized through X-ray diffraction, Raman spectroscopy, zeta potential, Fourier transform infrared spectroscopy (FT-IR), High-Resolution Transmission Electron Microscope (HR-TEM), and X-ray photoelectron spectroscopy (XPS) analysis. Under visible light irradiation, the CeO2-GOS nanocomposites photo catalyst exhibited 83%, 78%, and 70% degradation efficiencies for rhodamine B, methylene blue, and textile effluent, respectively. Due to the synergistic impact of GO, it act as an elastic conductive channel permitting improved charge transport, the fabricated CeO2-GOS nanocomposites showed a significant retort to photo catalysis of rhodamine B, methylene blue, and textile effluent. CeO2-GOS nanocomposites may yield unique insight into the synthesis of green nanocomposites and their application in environmental remediation due to their better photo catalytic activity.


Assuntos
Cério , Grafite , Nanocompostos , Nanopartículas , Catálise , Cério/química , Corantes/química , Grafite/química , Nanocompostos/química , Óxidos , Espectroscopia de Infravermelho com Transformada de Fourier , Têxteis
7.
Mater Chem Phys ; 287: 126249, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35581994

RESUMO

Almost existing anti-viral drugs are only organic molecules that are able to circumvent the system the virus works with, which leaves it facing the immune system of our bodies and then kills it. Unfortunately, this type of pharmacological fight did not succeed in a way to overcome this virus, so it became necessary to think outside the box, to find a drug that would kill the virus or alter its protein structure. This research aims to prepare silver nanoparticle (AgNPs) by the green method depending on the reaction of the silver nitrate (safe for humans) with the phoenix dactylifera extract (safe for humans) and then coated with the hydroxychloroquine (HQ, known antiviral drug). This substance will fight the virus with different mechanisms (i) silver will carry the drug to cells easily, and then (ii) nano silver will perform a physical inhibition of the virus and thus reduce its susceptibility to binding to host cells. In addition, (iii) silver nanoparticle is much smaller than the size of the virus which qualifies it to cross into the virus and change the structure of RNA. Furthermore, (iv) it is possible for silver to interact with the amino and carboxylic ends in the virus proteins. The results of TCID50 shows that the prepared nano drug is able to reduce the viability of covid-19 to about 22% using 400 mg/ml of AgNPs/HQ. The resulted nanodrug was also used for healing the wound infected with S. aureus and the histological results revealed that all of the disease symptoms improved, with the epidermal layer multiplying quickly and the infected wounds healing quickly.

8.
Molecules ; 27(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897850

RESUMO

The microwave (MW)-assisted direct esterification of certain P-acids is a green method. Quantum chemical calculations revealed that the activation enthalpy (ΔH#) for the exothermic monoalkylphosphate → dialkylphosphate transformation was on the average 156.6 kJ mol-1, while ΔH# for the dialkylphosphate → trialkylphosphate conversion was somewhat higher, 171.2 kJ mol-1, and the energetics of the elemental steps of this esterification was less favorable. The direct monoesterification may be performed on MW irradiation in the presence of a suitable ionic liquid additive. However, the second step, with the less favorable energetics as a whole, could not be promoted by MWs. Hence, dialkylphosphates had to be converted to triesters by another method that was alkylation. In this way, it was also possible to synthesize triesters with different alkyl groups. Eventually a green, P-chloride free MW-promoted two-step method was elaborated for the synthesis of phosphate triesters.


Assuntos
Líquidos Iônicos , Ácidos , Esterificação , Micro-Ondas , Termodinâmica
9.
J Sep Sci ; 43(15): 2981-2988, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32431004

RESUMO

Citicoline and piracetam were subjected separately to different stress conditions as recommended by the international conference on harmonization. In addition, new stability indicating thin layer chromatographic and ultra high performance liquid chromatographic methods have been developed and validated for simultaneous determination of citicoline and piracetam in presence of their degradation products. Separation on the proposed thin layer chromatographic method was carried out using a developing system containing methanol:chloroform:ammonium chloride buffer (9:1:2, v/v/v) on silica gel plates at 230 nm. On the other hand, the mobile phase in the ultra high performance liquid chromatographic method was composed of water (containing 0.1% triethylamine):ethanol (92:8, v/v). The flow rate was 1 mL/min and ultraviolet detection was at 230 nm. Moreover, results of the developed methods were statistically compared to those obtained by the reported high-performance liquid chromatography method and no significant difference between them was found. The greenness profile of ultra high performance liquid chromatographic method was assessed and compared with those of the previously published high-performance liquid chromatography methods, it was noticed that the proposed ultra high performance liquid chromatographic method more environmentally friendly and greener than other methods.


Assuntos
Citidina Difosfato Colina/análise , Piracetam/análise , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Composição de Medicamentos , Fotólise , Comprimidos , Temperatura
10.
Phytochem Anal ; 31(5): 575-582, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31997419

RESUMO

INTRODUCTION: Rosmarinic acid is a bioactive compound with various pharmaceutical effects and applications. OBJECTIVE: This work developed a new approach for aqueous enzymatic extraction of rosmarinic acid from the leaves of Salvia officinalis. METHODS: Different enzymes (proteases and cellulase) were evaluated for their extraction activity. Response surface methodology (RSM) was subsequently employed to optimise the extraction conditions. Thin layer chromatography was also used to identify rosmarinic acid in the extract of S. officinalis. RESULTS: Among the tested enzymes, a Cellulase A and Protamex mixture (1:1, w/w) exhibited maximum effectiveness in the extraction. Through the use of RSM, the maximum rosmarinic acid content of 28.23 ± 0.41 mg/g was obtained with enzyme loading of 4.49%, water-to-sample ratio of 25.76 mL/g, temperature of 54.3°C, and extraction time of 2 h. CONCLUSION: This study suggests that S. officinalis is a promising source of rosmarinic acid and aqueous enzymatic extraction is an efficient and ecofriendly method for extracting rosmarinic acid, with a short extraction time and without the contamination of a toxic solvent.


Assuntos
Salvia officinalis , Cinamatos , Depsídeos , Extratos Vegetais , Folhas de Planta , Ácido Rosmarínico
11.
Artigo em Inglês | MEDLINE | ID: mdl-32181694

RESUMO

In the past decade, Mexican coasts have received an enormous influx of macroalgae species, producing serious environmental and public health concerns. Here, we developed a green methodology to generate a new polymer from the lignin contained in the macroalgae. The methodology consists in lignin extraction-by-boiling and its subsequent polymerization with a laccase-like enzyme from the green algae Tetraselmis gracilis (Tg-laccase). Mass spectrometry revealed the presence of guaiacyl (G), p-hydroxyphenyl (H), and sinapyl alcohol as the main monolignols in the lignin from Sargassum sp. On the other hand, MALDI-TOF spectra shows an increase in the size of the lignin chain after enzymatic polymerization process with Tg-laccase. Besides, the characterization of the novel polymer -using 1H NMR, FTIR, SEC-FPLC, and UV/Vis- allowed establishing that during the polymerization process there is a decrease in the number of phenolic groups as well as loss of aromatic protons, which allowed proposing a polimerizacion mechanism. This methodology could be promising in the development of a new lignin-based polymer and would open a new direction for the environmental management of the macroalgae on the Mexican beaches.


Assuntos
Clorófitas/enzimologia , Química Verde/métodos , Lacase/química , Lignina/síntese química , Polimerização , Alga Marinha/química , Lignina/química , Peso Molecular , Fenóis/química
12.
J Food Sci Technol ; 57(4): 1233-1241, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32180619

RESUMO

Powdered soft drinks (PSDs), fortified with antioxidants such as ascorbic acid (AA), are normally controlled by titration or chromatographic methods. This study evaluated the feasibility of using near-infrared spectroscopy (NIRS) and multivariate analysis to predict AA contents in PSDs as an alternative not-destructive method. The AA content of sixty-seven samples of commercial fortified grape and passion fruit PSDs was analyzed by the standard method (titration) and showed significant variance between flavors within the same brand. In addition, 75% of the samples required from 0.3 to 10.2 more cups of grape than passion fruit flavor to supply the AA Reference Nutrient Intake for children and adults. Spectral and reference data sets were split into calibration and validation sets. Partial least squares regression models were built and validated for the determination of AA in both PSDs. The model's basic statistics for grape flavor PSDs (RMSEC = 0.49 mg g-1, Rcal 2 = 0.84; RMSECV = 0.67 mg g-1, RCV 2 = 0.70; RMSEP = 0.50 mg g-1, Rpred 2 = 0.84), and that for passion fruit flavor PSDs (RMSEC = 0.24 mg g-1, Rcal 2 = 0.95; RMSECV = 0.56 mg g-1, RCV 2 = 0.76; RMSEP de 0.57 mg g-1, Rpred 2 = 0.72) indicated that NIRS-PLS methodology produced reasonable results. The limits of detection and quantification obtained showed that the method is useful to detect and quantify AA in the studied samples. A new set of grape drinks was used for external prediction and the RMSEP was 0.62 mg g-1, Rpred 2 was 0.72. Based on the results, NIRS-multivariate analysis proved to be useful for quality control of AA in commercialized grape and passion fruit in PSDs and a faster, objective and environmentally friendly method alternative to standard methods.

13.
Chemistry ; 24(65): 17205-17209, 2018 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-30207397

RESUMO

An efficient electrochemical 1,2-sulfonylation/alkynylation of alkenes via radical 1,4-alkynyl migration of alkynyl-substituted tertiary alcohols is described, which used sodium sulfinates as sulfonyl sources affording the corresponding α-sulfonyl-ß-alkynylated products in moderate to excellent yields. This electrochemical reaction proceeds smoothly without the use of any metal catalyst, additive and oxidant and thus represents a new and eco-friendly strategy for the difunctionalization of unactive olefins, and also the first example of the electrochemical distal radical migration reaction.

14.
J Environ Sci (China) ; 73: 47-57, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30290871

RESUMO

Dyestuffs and heavy metal ions in water are seriously harmful to the ecological environment and human health. Three-dimensional (3D) flowerlike Fe(OH)3 microspheres were synthesized through a green yet low-cost injection method, for the removal of organic dyes and heavy metal ions. The Fe(OH)3 microspheres were characterized by thermal gravimetric analysis (TGA), Fourier transform infrared (FT-IR), and transmission electron microscopy (TEM) techniques. The adsorption kinetics of Congo Red (CR) on Fe(OH)3 microspheres obeyed the pseudo-second-order model. Cr6+ and Pb2+ adsorption behaviors on Fe(OH)3 microspheres followed the Langmuir isotherm model. The maximum adsorption capacities of the synthesized Fe(OH)3 were 308, 52.94, and 75.64mg/g for CR, Cr6+, and Pb2+ respectively. The enhanced adsorption performance originated from its surface properties and large specific surface area of 250m2/g. The microspheres also have excellent adsorption stability and recyclability. Another merit of the Fe(OH)3 material is that it also acts as a Fenton-like catalyst. These twin functionalities (both as adsorbent and Fenton-like catalyst) give the synthesized Fe(OH)3 microspheres great potential in the field of water treatment.


Assuntos
Compostos Férricos/química , Metais Pesados/química , Microesferas , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier
15.
Beilstein J Org Chem ; 11: 1985-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26664618

RESUMO

Secondary phosphine oxides react with vinyl sulfides (both alkyl- and aryl-substituted sulfides) under aerobic and solvent-free conditions (80 °C, air, 7-30 h) to afford 1-hydroxy-2-(organosulfanyl)ethyl(diorganyl)phosphine oxides in 70-93% yields.

16.
Food Chem ; 446: 138908, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38471413

RESUMO

In this study, we developed a low-energy-consumption green method for synthesising carbon dots (CD) at room temperature using watermelon rind as the carbon source through a cutting process based on NaCl crystals. The synthesis process was rapid (<5 min) and facile. The synthesised CD were characterised using photoluminescence (PL) spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, energy-dispersive X-ray analysis and X-ray photoelectron spectroscopy. The results revealed that the synthesised dots exhibited robust adsorption, a spherical shape and a uniform size distribution. The PL intensity of the quantum dots decrease due to the temperature rising, metal ions and ponceau 4R added. In contrast with PH, PL intensity increase, so these CD can serve as multifunctional sensing materials. Overall, this study presents an environmentally friendly method for the rapid synthesis of CD that are suitable for temperature, pH, metal ion and food sensing applications.


Assuntos
Pontos Quânticos , Eliminação de Resíduos , Temperatura , Perda e Desperdício de Alimentos , Carbono/química , Alimentos , Pontos Quânticos/química
17.
Food Chem ; 460(Pt 1): 140461, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39047481

RESUMO

This study endeavors to examine the levels of risk factors in alcoholic beverages and propose mitigation strategies. GC-MS analysis was utilized to assess risk factors in various distilled-spirits. The content of such risk factors in spirits ranked as follows: vodka ≈ gin < baijiu < whiskey < brandy, and all were adhering to the Chinese national standard. Additionally, a method was refined to alleviate these risks, employing various reagents for activated carbon modification and evaluating their adsorption efficiency for risk factors reduction. Oxalic acid-modified activated carbon exhibited promising adsorption rates for risk factors with acceptable flavor compounds loss, rendering it a prospective solution for health hazard reduction. Characterization via SEM and nitrogen-adsorption-desorption was conducted on the optimal material, complemented by sensory experiments to optimize its application. This study offers valuable insights into the content of risk factors in alcoholic beverages, aiding in improving quality and safety of alcoholic beverages.

18.
ACS Appl Mater Interfaces ; 16(17): 22421-22432, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38634639

RESUMO

Lanthanides are largely used in optoelectronics as dopants to enhance the physical and optical properties of semiconducting devices. In this study, lanthanum(III)hydroxide nanoparticles (La(OH)3NPs) are used as a dopant of polyethylenimine (PEI)-functionalized nitrogen (N)-doped graphene quantum dots (PEI-NGQDs). The La(OH)3NPs-dopedPEI-NGQDs nanocomposites are prepared from La(NO)3 in a single step by a green novel method and are characterized by Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Deposited over an n-type Si wafer, the La(OH)3NPs-dopedPEI-NGQDs nanocomposites form Schottky diodes. The I-V characteristics and the photoresponse of the diodes are investigated as a function of the illumination intensity in the range 0-110 mW cm-2 and at room temperature. It is found that the rectification ratio and ideality factor of the diode decrease, while the Schottky barrier and series resistance increase with the enhancing illuminations. As a photodetector, the La(OH)3NPs-dopedPEI-NGQDs/n-Si heterojunction exhibits an appreciable responsivity of 3.9 × 10-3 AW-1 under 22 mW cm-2 at -0.3 V bias and a maximum detectivity of 8.7 × 108 Jones under 22 mW cm-2 at -0.5 V. This study introduces the green synthesis and presents the structural, electrical, and optoelectronic properties of La(OH)3NPs-dopedPEI-NGQDs, demonstrating that these nanocomposites can be promising for optoelectronic applications.

19.
J Colloid Interface Sci ; 648: 78-89, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37295372

RESUMO

Two novel MOF- ethyl cellulose (EC)- based nanocomposites have been designed and synthesized in water by electrospinning and applied for adsorption of congo red (CR) in water. Nano- Zeolitic Imidazolate Framework-67 (ZIF-67), and Materials of Institute Lavoisier (MIL-88A) were synthesized in aqueous solutions by a green method. To enhance the dye adsorption capacity and stability of MOFs, they have been incorporated into EC nanofiber to prepare composite adsorbents. The performance of both composites in the absorption of CR, a common pollutant in some industrial wastewaters, has then been investigated. Various parameters including initial dye concentration, the dosage of the adsorbent, pH, temperature and contact time were optimized. The results indicated 99.8 and 90.9% adsorption of CR by EC/ZIF-67 and EC/MIL-88A, respectively at pH = 7 and temperature at 25 °C after 50 min. Furthermore, the synthesized composites were separated conveniently and successfully reused five times without significant loss of their adsorption activity. For both composites, the adsorption behavior can be explained by pseudo-second-order kinetics, Intraparticular diffiusion and Elovich models demonstrated that the experimental data well matched to the pseudo-second-order kinetics. Intraparticular diffiusion model showed that the adsorption of CR on EC/ZIF-67 and EC/MIL-88a took place in one and two steps, respectively. Freundlich isotherm models and thermodynamic analysis indicated exothermic and spontaneous adsorption.

20.
Antibiotics (Basel) ; 12(8)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37627671

RESUMO

Copper oxide nanoparticles (CuONPs) were synthesized using an eco-friendly method and their antimicrobial and biocompatibility properties were determined. The supernatant and extract of the fungus Ganoderma sessile yielded small, quasi-spherical NPs with an average size of 4.5 ± 1.9 nm and 5.2 ± 2.1 nm, respectively. Nanoparticles were characterized by UV-Vis spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS), and zeta potential analysis. CuONPs showed antimicrobial activity against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Pseudomonas aeruginosa (P. aeruginosa). The half-maximal inhibitory concentration (IC50) for E. coli was 8.5 µg/mL, for P. aeruginosa was 4.1 µg/mL, and for S. aureus was 10.2 µg/mL. The ultrastructural analysis of bacteria exposed to CuONPs revealed the presence of small CuONPs all through the bacterial cells. Finally, the toxicity of CuONPs was analyzed in three mammalian cell lines: hepatocytes (AML-12), macrophages (RAW 264.7), and kidney (MDCK). Low concentrations (<15 µg/mL) of CuONPs-E were non-toxic to kidney cells and macrophages, and the hepatocytes were the most susceptible to CuONPs-S. The results obtained suggest that the CuONPs synthesized using the extract of the fungus G. sessile could be further evaluated for the treatment of superficial infectious diseases.

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