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1.
Heliyon ; 10(11): e31352, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38828346

RESUMEN

In the past few years, nanotechnology has emerged as one of the most interesting and cutting-edge research areas across all disciplines. Nanotechnology allows progress in all science fields to make novel materials and industry-different devices. Generally, nanoparticle synthesis methods are chemical, physical, and biological. The chemical and physical techniques use potentially harmful compounds, and the expense of these processes renders them unsuitable for nanoparticle synthesis. In light of this, it needs development strategies that are sustainable, economical, and eco-friendly viable. Through, biosynthesis, nanoparticles can overcome these disadvantages. One of the biological strategies is the myco-synthesis method, which connects the fields of mycology and nanotechnology. In this study, magnetite (Fe3O4) NPs have been synthesized using a myco-synthesis method by selecting Aspergillus elegans as a fungal species. Two extracts were used, growth medium and an aqueous extract. A comparative analysis between nanoparticles synthesized through myco-synthesis and those produced using conventional chemical methods has been conducted to substantiate the significance of the biological approach. The results of this study unequivocally establish that myco-synthesized nanoparticles exhibit superior and enhanced characteristics compared to those synthesized through chemical means, as ascertained through a comprehensive array of characterization techniques employed throughout the investigation. This contrast is observable in terms of the aggregation state, the existence of capping and stabilizing agents enveloping the nanoparticles, their magnetic and thermal attributes, and the enduring stability of these nanoparticles. These results highlight the significant promise of employing phytochemicals extracted from Aspergillus elegans as a highly suitable option for the biofabrication of Fe3O4 nanoparticles.

2.
Chem Biol Drug Des ; 103(4): e14513, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38570322

RESUMEN

Taxol (paclitaxel) is the first approved microtubule-stabilizing agent (MSA) by binding stoichiometrically to tubulin, which is considered to be one of the most significant advances in first-line chemotherapy against diverse tumors. However, a large number of residue missence mutations harboring in the tubulin have been observed to cause acquired drug resistance, largely limiting the clinical application of Taxol and its analogs in chemotherapy. A systematic investigation of the intermolecular interactions between the Taxol and various tubulin mutants would help to establish a comprehensive picture of drug response to tubulin mutations in clinical treatment of cancer, and to design new MSA agents with high potency and selectivity to overcome drug resistance. In this study, we described an integration of in silico analysis and in vitro assay (iSiV) to profile Taxol against a panel of 149 clinically observed, cancer-associated missence mutations in ß-tubulin at molecular and cellular levels, aiming to a systematic understanding of molecular mechanism and biological implication underlying drug resistance and sensitivity conferring from tubulin mutations. It is revealed that the Taxol-resistant mutations can be classified into three types: (I) nonbonded interaction broken due to mutation, (II) steric hindrance caused by mutation, and (III) conformational change upon mutation. In addition, we identified three new Taxol-resistant mutations (C239Y, T274I, and R320P) that can largely reduce the binding affinity of Taxol to tubulin at molecular level, in which the T274I and R320P were observed to considerably impair the antitumor activity of Taxol at cellular level. Moreover, a novel drug-susceptible mutation (M363T) was also identified, which improves Taxol affinity by 2.6-fold and decreases Taxol antitumor EC50 values from 29.4 to 18.7 µM.


Asunto(s)
Paclitaxel , Tubulina (Proteína) , Paclitaxel/farmacología , Tubulina (Proteína)/metabolismo , Microtúbulos/metabolismo , Mutación , Resistencia a Medicamentos
3.
Biomed Phys Eng Express ; 10(3)2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38513277

RESUMEN

Iron oxide nanoparticles (Fe2O3NPs) were synthesized utilizingMentha spicatasourced from Cyprus as a stabilizing agent. The study delved into assessing the antimicrobial, cytotoxic, anti-proliferative, and anti-migratory potential of Fe2O3 NPs through disc diffusion, trypan blue, and 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay, respectively. Characterization of the synthesized Fe2O3 NPs was conducted using Fourier-transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), UV-vis spectroscopy (UV-vis), scanning electron microscopy (SEM), and energy-dispersive x-ray spectroscopy (EDX). The FTIR, XRD, and SEM-EDX spectra confirmed the successful formation of Fe2O3 NPs. The analysis of UV-vis spectra indicates an absorption peak at 302 nm, thereby confirming both the successful synthesis and remarkable stability of the nanoparticles. The nanoparticles exhibited uniform spherical morphology and contained Fe, O, and N, indicating the synthesis of Fe2O3NPs. Additionally, the Fe2O3NPs formed through biosynthesis demonstrated antimicrobial capabilities againstEscherichia coliandBacillus cereus. The significant anti-migratory potential on MDA-MB 231 human breast cancer cells was observed with lower concentrations of the biosynthesized Fe2O3NPs, and higher concentrations revealed cytotoxic effects on the cells with an IC50of 95.7µg/ml. Stable Fe2O3NPs were synthesized usingMentha spicataaqueous extract, and it revealed antimicrobial activity onE. coliandB. cereus, cytotoxic, anti-proliferative and anti-migratory effect on highly metastatic human breast cancer cell lines.


Asunto(s)
Antiinfecciosos , Neoplasias de la Mama , Nanopartículas del Metal , Humanos , Femenino , Compuestos Férricos/química , Nanopartículas del Metal/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antiinfecciosos/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Neoplasias de la Mama/tratamiento farmacológico , Nanopartículas Magnéticas de Óxido de Hierro
4.
ChemistryOpen ; 12(10): e202300094, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37803419

RESUMEN

The choice of capping agents used during the synthesis process of quantum dots (QDs) can significantly influence their fate and fundamental properties. Hence, choosing an appropriate capping agent is a critical step in both synthesis and biomedical application of QDs. In this research, ZnS QDs were synthesized via chemical precipitation process and three commonly employed capping agents, namely mercaptoethanol (ME), mercaptoacetic acid (MAA), and cysteamine (CA), were used to stabilize the QDs. This study was aimed to examine how these capping agents impact the physicochemical and optical characteristics of ZnS QDs, as well as their interactions with biological systems. The findings revealed that the capping agents had considerable effects on the behavior and properties of ZnS QDs. MAA-QD exhibited superior crystal lattice, smaller size, and significant quantum yield (QY). In contrast, CA-QDs demonstrated the lowest QY and the highest tendency for aggregation. ME-QDs exhibited intermediate characteristics, along with an acceptable level of cytotoxicity, rapid uptake by cells, and efficient escape from lysosomes. Consequently, it is advisable to select capping agents in accordance with the specific objectives of the research.


Asunto(s)
Puntos Cuánticos , Puntos Cuánticos/toxicidad , Puntos Cuánticos/química , Sulfuros/química , Compuestos de Zinc/química , Lisosomas
5.
Cancers (Basel) ; 15(13)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37444418

RESUMEN

A variety of microtubule-stabilizing cytotoxic agents (MSA) with diverse chemical scaffolds have been discovered from marine sponges, microorganisms, and plants. Two MSAs, docetaxel and cabazitaxel, are the exclusive chemotherapeutics that convey a survival benefit in patients with castration-resistant prostate cancer (CRPC). Additional MSAs have been investigated for their potential in treating prostate cancer in both clinical and preclinical settings. Independent of promoting mitotic arrest, MSAs can suppress the nuclear accumulation of androgen receptor (AR), which is the driving force for prostate cancer cell growth and progression. The alternative mechanism not only helps to better understand the clinical efficacy of docetaxel and cabazitaxel for AR-driven CRPC but also provides an avenue to seek better treatments for various forms of prostate cancer. The dual mechanisms of action enable MSAs to suppress AR-null prostate cancer cell proliferation by cell mitosis pathway and to interfere with the AR signaling pathway in AR positive cells. MSA chemotherapeutics, being administered alone or in combination with other therapeutics, may serve as the optimal therapeutic option for patients with either castration-sensitive or castration-resistant prostate cancer. This review provides an overview of the anti-prostate cancer profiles (including preclinical and clinical studies, and clinical use) of diverse MSAs, as well as the mechanism of action.

6.
Front Microbiol ; 14: 1119550, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36846763

RESUMEN

The antibacterial properties of nanoparticles are of particular interest because of their potential to serve as an alternative therapy to combat antimicrobial resistance. Metal nanoparticles such as silver and copper nanoparticles have been investigated for their antibacterial properties. Silver and copper nanoparticles were synthesized with the surface stabilizing agents cetyltrimethylammonium bromide (CTAB, to confer a positive surface charge) and polyvinyl pyrrolidone (PVP, to confer a neutral surface charge). Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and viable plate count assays were used to determine effective doses of silver and copper nanoparticles treatment against Escherichia coli, Staphylococcus aureus and Sphingobacterium multivorum. Results show that CTAB stabilized silver and copper nanoparticles were more effective antibacterial agents than PVP stabilized metal nanoparticles, with MIC values in a range of 0.003 µM to 0.25 µM for CTAB stabilized metal nanoparticles and 0.25 µM to 2 µM for PVP stabilized metal nanoparticles. The recorded MIC and MBC values of the surface stabilized metal nanoparticles show that they can serve as effective antibacterial agents at low doses.

7.
J Labelled Comp Radiopharm ; 66(3): 73-85, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36656923

RESUMEN

Angiotensin II type 1 receptors (AT1 R) blocker losartan is used in patients with renal and cardiovascular diseases. [18 F]fluoropyridine-losartan has shown favorable binding profile for quantitative renal PET imaging of AT1 R with selective binding in rats and pigs, low interference of radiometabolites and appropriate dosimetry for clinical translation. A new approach was developed to produce [18 F]fluoropyridine-losartan in very high molar activity. Automated radiosynthesis was performed in a three-step, two-pot, and two-HPLC-purification procedure within 2 h. Pure [18 F]FPyKYNE was obtained by radiofluorination of NO2 PyKYNE and silica-gel-HPLC purification (40 ± 9%), preventing the formation of nitropyridine-losartan in the second step. Conjugation with trityl-losartan azide via click chemistry, followed by acid hydrolysis, C18-HPLC purification and reformulation provided [18 F]fluoropyridine-losartan in 11 ± 2% (decay-corrected from [18 F]fluoride, EOB). Using tris[(1-(3-hydroxypropyl)-1H-1,2,3-triazol-4-yl)methyl]-amine (THPTA) as a Cu(I)-stabilizing agent for coupling [18 F]FPyKYNE to the unprotected losartan azide afforded [18 F]fluoropyridine-losartan in similar yields (11 ± 3%, decay-corrected from [18 F]fluoride, EOB). Reverse-phase HPLC was optimized by reducing the pH of the mobile phase to achieve complete purification and high molar activities (467 ± 60 GBq/µmol). The use of radioprotectants prevented tracer radiolysis for 10 h (RCP > 99%). The product passed the quality control testing. This reproducible automated radiosynthesis process will allow in vivo PET imaging of AT1 R expression in several diseases.


Asunto(s)
Angiotensina II , Losartán , Animales , Humanos , Ratas , Azidas , Fluoruros , Radioisótopos de Flúor , Tomografía de Emisión de Positrones/métodos , Porcinos
8.
Foods ; 11(12)2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-35741874

RESUMEN

Flaxseed contains significant concentration of mucilage or gum (a type of hydrocolloid). Flaxseed mucilage (FM) predominantly occurs in the outermost layer of the seed's hull and is known to possess numerous health benefits such as delayed gastric emptying, reduced serum cholesterol, and improved glycemic control. FM is typically composed of an arabinoxylan (neutral in nature) and a pectic-like material (acidic in nature). Similar to gum arabic, FM exhibits good water-binding capacity and rheological properties (similar functionality); therefore, FM can be used as its replacement in foods. In this review, an overview of methods used for FM extraction and factors influencing the extraction yield were discussed initially. Thereafter, food applications of FM as gelling agent/gel-strengthening agent, structure-forming agent, stabilizing agent, fat replacer, anti-retrogradation agent, prebiotic, encapsulating agent, edible coatings and films/food packaging material, and emulsifier/emulsion stabilizer were included. At the end, some limitations to its wide application and potential solutions were added.

9.
Molecules ; 26(13)2021 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34202852

RESUMEN

Nano-based particles synthesized via green routes have a particular structure that is useful in biomedical applications as they provide cheap, eco-friendly, and non-toxic nanoparticles. In the present study, we reported the effect of various concentrations of Zinc oxide nanoparticles synthesized using A. lebbeck stem bark extract (ZnO NPsAL) as stabilizing agent on rat biochemical profiles and tissue morphology. Adult Wistar rats weighing 170 ± 5 g were randomly classified into eight groups of five rats each; Group A served as a control fed with normal diet and water. Groups B1, B2, C1, C2, D1, D2, and E were treated with 40 mg/kg and 80 mg/kg of the 0.01, 0.05, and 0.1 M biosynthesized ZnO NPsAL and zinc nitrate daily by the gavage method, respectively. The rats were anesthetized 24 h after the last treatment, blood samples, kidney, heart, and liver tissues were collected for biochemical and histopathological analysis. The rats mean body weight, serum alkaline phosphatase, alanine aminotransferase, creatinine, urea, bilirubin, protein, albumin, globulin, total cholesterol, triacylglycerol, and high-density lipoprotein were significantly altered with an increased concentration of biosynthesized ZnO NPsAL when compared with the control group (p < 0.05; n ≥ 5). Furthermore, histopathological analysis of treated rats' kidney, heart, and liver tissue revealed vascular congestion, tubular necrosis, inflammation, and cytoplasmic vacuolation. Biosynthesized ZnO NPsAL showed significant alteration in biochemical parameters and tissue morphology in rats with increasing concentrations of the nanoparticles.


Asunto(s)
Albizzia/química , Nanopartículas , Corteza de la Planta/química , Extractos Vegetales/química , Óxido de Zinc , Animales , Masculino , Nanopartículas/administración & dosificación , Nanopartículas/química , Nanopartículas/uso terapéutico , Especificidad de Órganos , Ratas , Ratas Wistar , Óxido de Zinc/efectos adversos , Óxido de Zinc/química , Óxido de Zinc/farmacología
10.
Chemosphere ; 285: 131499, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34265715

RESUMEN

Cadmium (Cd) exposure is related to a multitude of adverse health outcomes because food crops grown on Cd-polluted soil are widely consumed by the public. The present study investigates the different application techniques of a combined amendment (lime + zeolite + biochar + compost, LZBC) for soil Cd immobilization effect on growth performance, Cd uptake by the second season crops, and soil quality in greenhouse vegetable production (GVP) under a rotation system. Five fruit vegetables were cultivated as the second season crop in the same plots which have been used for pakchoi as the first season crop (with or without LZBC application). The results indicated that LZBC with the consecutive application (T3) promoted crops biomass and fruit yield the most, followed by LZBC with the second crop application (T2) and LZBC with the first crop application (T1). LZBC application showed increasing rhizosphere soil pH and improvement in soil fertility of all crops including available nitrogen, available phosphorus, available potassium, organic matter, and cation exchange capacity. LZBC had positive influences on soluble sugar, soluble protein, and vitamin C in edible parts of 5 vegetables. Cd contents in fruit, shoot, and root of eggplant, pimento, cowpea, and tomato except cucumber were reduced by adding LZBC. As for the economic performance, T3 had the highest output/input ratio in general. Overall, these results demonstrated that T3 was dramatically more effective for minimizing health risk, increasing production, and facilitating sustainable utilization of soil under the Cd-contaminated GVP system.


Asunto(s)
Cadmio , Contaminantes del Suelo , Adsorción , Cadmio/análisis , Frutas/química , Suelo , Contaminantes del Suelo/análisis , Verduras
11.
Chemosphere ; 281: 130661, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34029959

RESUMEN

Textile industry is one of the most environmental unfriendly industrial processes due to the massive generation of colored wastewater contaminated with dyes and other chemical auxiliaries. These contaminants are known to have undesirable consequences to ecosystem. The present study investigated the best operating parameters for the removal of congo red (CR, as the model for dye wastewater) by orange peels extract biosynthesized zinc oxide nanoparticles (ZnO NPs) via photocatalysis in an aqueous solution. The response surface methodology (RSM) with ZnO NPs loadings (0.05-0.20 g), pH (3.00-11.00), and initial CR concentration (5-20 ppm) were used for the optimization process. The applicability of ZnO NPs in the dye wastewater treatment was evaluated based on the techno-economic analysis (TEA). ZnO NPs exhibited hexagonal wurtzite structure with = C-H, C-O, -C-O-C, CC, O-H as the main functional groups. The maximum degradation of CR was more than 96% with 0.171 g of ZnO NPs, at pH 6.43 and 5 ppm of CR and 90% of the R2 coefficient. The specific cost of ZnO NPs production is USD 20.25 per kg. These findings indicated that the biosynthesized ZnO NPs with orange peels extract provides alternative method for treating dye wastewater.


Asunto(s)
Citrus sinensis , Nanopartículas , Óxido de Zinc , Rojo Congo , Ecosistema , Extractos Vegetales , Textiles , Aguas Residuales
12.
Nanomaterials (Basel) ; 10(10)2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-33007984

RESUMEN

Engineered nanoparticles are utilized as drug delivery carriers in modern medicine due to their high surface area and tailorable surface functionality. After in vivo administration, nanoparticles distribute and interact with biomolecules, such as polar proteins in serum, lipid membranes in cells, and high ionic conditions during digestion. Electrostatic forces and steric hindrances in a nanoparticle population are disturbed and particles agglomerate in biological fluids. Little is known about the stability of nanoparticles in relation to particle surface charge. Here, we compared three different surface-stabilized silver nanoparticles (50 nm) for intracellular agglomeration in human hepatocellular carcinoma cells (HepG2). Nanoparticles stabilized with branched polyethyleneimine conferred a positive surface charge, particles stabilized with lipoic acid conferred a negative surface charge, and particles stabilized with polyethylene glycol conferred a neutral surface charge. Particles were incubated in fetal bovine serum, simulated lung surfactant fluid, and simulated stomach digestion fluid. Each nanoparticle system was characterized via microscopic (transmission electron, fluorescence, and enhanced darkfield) and spectroscopic (hyperspectral, dynamic light scattering, and ultraviolet-visible absorption) techniques. Results showed that nanoparticle transformation included cellular internalization, agglomeration, and degradation and that these changes were dependent upon surface charge and incubation matrix. Hyperspectral analyses showed that positively charged silver nanoparticles red-shifted in spectral analysis after transformations, whereas negatively charged silver nanoparticles blue-shifted. Neutrally charged silver nanoparticles did not demonstrate significant spectral shifts. Spectral shifting indicates de-stabilization in particle suspension, which directly affects agglomeration intracellularly. These characteristics are translatable to critical quality attributes and can be exploited when developing nano-carriers for nanomedicine.

13.
Carbohydr Polym ; 245: 116513, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32718623

RESUMEN

The silver nanoparticles (AgNPs) can exhibit different optical properties depending on their size and shape as a result of synthesis method and the stabilizer used. In this research the synthesis of AgNPs in the presence of nanocellulose obtained from carrot pomace was investigated. The influence of silver nitrate concentration, temperature and mechanical agitation on size and shape of AgNPs was studied. The mixing of reagents during synthesis, regardless temperature, led to obtain AgNPs of various sizes and shapes. It was confirmed by different colors of samples with absorbance maximum from 334 to 779 nm, the transmission electron microscopy images and dynamic light scattering results. In unmixed samples only spherical nanoparticles with absorbance maximum at 408 nm were observed. Obtained results have demonstrated that mechanical agitation and an appropriate silver nitrate concentration combined with stabilizing effect of nanocellulose allow to obtain AgNPs in different shapes and sizes.


Asunto(s)
Celulosa/química , Daucus carota/química , Excipientes/química , Tecnología Química Verde/métodos , Nanopartículas del Metal/química , Extractos Vegetales/química , Nitrato de Plata/química , Técnicas de Química Sintética/métodos , Dispersión Dinámica de Luz , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Temperatura
14.
Curr Org Synth ; 17(7): 558-566, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32598261

RESUMEN

AIM: The study aimed at synthesizing ZnO NPs using Petroselinum crispum extract, commonly known as parsley, as a source of biosynthesis without utilizing chemical agents for reducing, capping and stabilizing agent. BACKGROUND: Recently, the biosynthesis of nanoparticles has been widely explored due to the wide range of vital applications in nanotechnology. Biosynthesized zinc oxide nanoparticles, ZnO NPs, have become increasingly important since they have many applications and are environmentally friendly. METHODS: The innovation of this investigation is that the nanosized ZnO NPs can be formed from one-pot reaction without utilizing any external stabilizing and reducing agent which is not plausible via the current procedures. RESULTS: The biosynthesized ZnO NPs were characterized using UV-Vis spectroscopy, FT-IR spectroscopy, X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDX) to investigate the optical, chemical, structural, and morphological properties. CONCLUSION: These techniques exhibited that the property of the biosynthesized ZnO NPs is analogous with the standard NPs prepared from dissimilar methods. Investigating the plausible mechanism of formation and stabilization of ZnO NPs by biomolecules of Petroselinum crispum leaf extract was another vital feature of this study.


Asunto(s)
Nanopartículas del Metal/química , Petroselinum/química , Extractos Vegetales/química , Hojas de la Planta/química , Óxido de Zinc/química , Tecnología Química Verde/métodos , Óxido de Zinc/síntesis química
15.
Environ Pollut ; 255(Pt 1): 113124, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31622956

RESUMEN

The transport and retention behavior of polymer- (PVP-AgNP) and surfactant-stabilized (AgPURE) silver nanoparticles in carbonate-dominated saturated and unconsolidated porous media was studied at the laboratory scale. Initial column experiments were conducted to investigate the influence of chemical heterogeneity (CH) and nano-scale surface roughness (NR) arising from mixtures of clean, positively charged calcium carbonate sand (CCS), and negatively charged quartz sands. Additional column experiments were performed to elucidate the impact of CH and NR arising from the presence and absence of soil organic matter (SOM) on a natural carbonate-dominated aquifer material. The role of the nanoparticle capping agent was examined under all conditions tested in the column experiments. Nanoparticle transport was well described using a numerical model that facilitated blocking on one or two retention sites. Results demonstrate that an increase in CCS content in the artificially mixed porous medium leads to delayed breakthrough of the AgNPs, although AgPURE was much less affected by the CCS content than PVP-AgNPs. Interestingly, only a small portion of the solid surface area contributed to AgNP retention, even on positively charged CCS, due to the presence of NR which weakened the adhesive interaction. The presence of SOM enhanced the retention of AgPURE on the natural carbonate-dominated aquifer material, which can be a result of hydrophobic or hydrophilic interactions or due to cation bridging. Surprisingly, SOM had no significant impact on PVP-AgNP retention, which suggests that a reduction in electrostatic repulsion due to the presence of SOM outweighs the relative importance of other binding mechanisms. Our findings are important for future studies related to AgNP transport in shallow unconsolidated calcareous and siliceous sands.


Asunto(s)
Carbonato de Calcio/análisis , Nanopartículas del Metal/análisis , Compuestos Orgánicos/química , Plata/análisis , Suelo/química , Agua Subterránea/química , Interacciones Hidrofóbicas e Hidrofílicas , Polímeros/química , Porosidad , Cuarzo/química , Suelo/clasificación , Tensoactivos
16.
Mikrochim Acta ; 186(7): 422, 2019 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-31187298

RESUMEN

A rapid method for the sensitive detection of phenytoin (PHT) by branched gold nanoparticles (B-AuNPs) is described. These nanoparticles were synthesized by adding methanol as the reducing agent and poly(ethylene glycol) as the stabilizer at 70 °C. The B-AuNPs are red in color with an absorption maximum at 540 nm when prepared in situ. However, the color becomes increasingly weaker when PHT is present in increasing concentrations. This method can determine PHT over the 67-670 ng·mL-1 concentration range, with detection limit of 21 ng·mL-1. The relative standard deviation for five replicate measurements at 68 and 530 ng·mL-1 of PHT was 3.2% and 1.2%, respectively. The method was applied to the determination of PHT in plasma samples of epileptic patients, and the results were in agreement with those obtained by a standard official method. Graphical abstract Branched gold nanoparticles (AuNPs) prepared in situ have a red color with an absorption maximum at 540 nm. The color becomes increasingly weaker with decreasing the intensity of the characteristic SPR band when PHT is present in increasing concentration. The current assay is capable of determining PHT over the 67-670 ng·mL-1 concentration range with a limit of detection of 21 ng·mL-1.


Asunto(s)
Nanopartículas del Metal/química , Fenitoína/sangre , Colorimetría/métodos , Monitoreo de Drogas/métodos , Oro/química , Humanos , Límite de Detección , Espectrofotometría/métodos
18.
Chemistry ; 24(52): 13815-13820, 2018 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-29975430

RESUMEN

Li2 CO3 -passivated Li3 N with high stability is prepared by aging Li3 N powder in dry air, and is then used as an electrode additive for a Li(Li0.18 Ni0.15 Co0.15 Mn0.52 )O2 (LLMO) cathode material. The material shows a large irreversible capacity of 800 mA h g-1 during the first charge, with the formation of a Li2 N intermediate product. Acting as a Li+ sacrificial salt for a LLMO(+)/graphite(-) Li-ion battery, 2 wt % Li3 N results in a 10 % increase in discharge capacity. The Li2 N intermediate product reacts with the electrolyte, forming a uniform and regular surface film on the cathode. Moreover, chemical bonding between LLMO and N improves the electrode stability, resulting in excellent electrochemical performance.

19.
J Neuroimmunol ; 322: 36-45, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-29937116

RESUMEN

Alteration in cytokine levels, particularly, IL-6, TNF-α, IL-1ß and IL-2, has been implicated in the pathogenesis of epilepsy and bipolar disorder. Lamotrigine (LTG), an antiepileptic drug with mood stabilizing properties, has documented immunomodulatory effects. However, its effect on cytokine secretion in vivo has not been examined. Besides, studies have reported inconsistent results of the in vitro effects of LTG on cytokine secretion. Hence, we used murine models of inflammation to characterize the in vivo and the in vitro effects of LTG on the secretion of the aforementioned cytokines, using ELISA. LTG significantly inhibited basal and mitogen-induced IL-6, TNF-α and IL-1ß secretion in vivo and in LPS-treated RAW264.7 cells in vitro. In PMs, LTG inhibited basal and LPS-induced IL-6 and TNF-α secretion. Our findings extend the current understanding of the anti-inflammatory properties of LTG and may be relevant to its role in modulating the immune system in epilepsy and bipolar disorder.


Asunto(s)
Anticonvulsivantes/farmacología , Citocinas/metabolismo , Inflamación/fisiopatología , Lamotrigina/farmacología , Animales , Concanavalina A/farmacología , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Lipopolisacáridos/farmacología , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/metabolismo , Ratones , Ratones Endogámicos BALB C , Células RAW 264.7
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 204: 232-240, 2018 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-29936220

RESUMEN

GCMO NSs were synthesized by the reaction of metal nitrate salts in the presence of stabilizing agent and PG, by a Pechini method. Citric acid, maleic acid, succinic acid and 1,3,5-benzenetricarboxylic acid were used as stabilizing agents. The structure, morphology, optical, magnetic and photocatalytic properties of the GCMO NSs were investigated using various characterization techniques. Effects of type of stabilizing agent, the molar ratio of stabilizing agent:PG and also calcination temperature on particle size and morphology of the products were investigated. Also the influence of kind of pollutant on photocatalytic behavior of GCMO NSs was evaluated.

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