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1.
Int J Nanomedicine ; 16: 2187-2201, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33758506

RESUMEN

The physicochemical and optical properties of silver nanoparticles (SNPs) and gold nanoparticles (GNPs) have allowed them to be employed for various biomedical applications, including delivery, therapy, imaging, and as theranostic agents. However, since they are foreign body systems, they are usually redistributed and accumulated in some vital organs, which can produce toxic effects; therefore, this a crucial issue that should be considered for potential clinical trials. This review aimed to summarize the reports from the past ten years that have used SNPs and GNPs for in vivo studies on the diagnosis and treatment of brain diseases and those related to the central nervous system, emphasizing their toxicity as a crucial topic address. The article focuses on the effect of the nanoparticle´s size and chemical composition as relevant parameters for in vivo toxicity. At the beginning of this review, the general toxicity and distribution studies are discussed separately for SNPs and GNPs. Subsequently, this manuscript analyzes the principal applications of both kinds of nanoparticles for glioma, neurodegenerative, and other brain diseases, and discusses the advances in clinical trials. Finally, we analyze research prospects towards clinical applications for both types of metallic nanoparticles.


Asunto(s)
Enfermedades del Sistema Nervioso Central/patología , Oro/química , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Tamaño de la Partícula , Plata/química , Pruebas de Toxicidad , Animales , Humanos , Nanopartículas del Metal/ultraestructura , Distribución Tisular/efectos de los fármacos
2.
Int J Nanomedicine ; 16: 1757-1773, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33688190

RESUMEN

Background: NiO nanoparticles have attracted much attention due to their unique properties. They have been synthesized using chemical and physical techniques that often need toxic chemicals. These toxic chemicals cannot easily be removed from the nanoparticle's surface, make them less biocompatible, and limit their biological applications. Instead, plants based green synthesis of nanoparticles uses phytomolecules as reducing and capping agents. These phytomolecules are biologically active with no or less toxic effects. Materials and Methods: Phytomolecules-coated NiO nanoparticles were synthesized employing a green route using Abutilon indicum leaf extract. For comparative study, we also have synthesized NiO nanoparticles using the co-precipitation method. Synthesized nanoparticles were successfully characterized using different spectroscopic techniques. The synthesized nanoparticles were evaluated for antibacterial activity with agar well diffusion assay against different bacteria compared to standard drug and plant extract. They are also examined for anticancer potential using MTT assay against HeLa cancer cells, and further, their antioxidant potential was determined using DPPH assay. Biocompatibility of the synthesized nanoparticles was assessed against fibroblast cells. Results: Phytomolecules-coated NiO nanoparticles were demonstrated superior antibacterial and anticancer performance against bacteria (E. coli, B. bronchiseptica, B. subtilis, and S. aureus) by presenting highest zone of inhibitions (18 ± 0.58 mm, 21 ± 0.45 mm, 22 ± 0.32 mm, and 23 ± 0.77 mm) and HeLa cancer cells by exhibiting the least cell viability percentage (51.74 ± 0.35%) compared to plant extract and chemically synthesized NiO nanoparticles but were comparable to standard antibiotic and anticancer drugs, respectively. Phytomolecules-coated NiO nanoparticles were also demonstrated excellent antioxidant activity (79.87 ± 0.43% DPPH inhibition) and biocompatibility (> 90% cell viability) with fibroblast cells. Conclusion: Nanoparticle synthesis using the Abutilon indicum leaf extract is an efficient and economical method, produces biocompatible and more biologically active nanoparticles, which can be an excellent candidate for therapeutic applications.


Asunto(s)
Antiinfecciosos/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Malvaceae/química , Nanopartículas del Metal/química , Fitoquímicos/química , Extractos Vegetales/química , Hojas de la Planta/química , Bacterias/efectos de los fármacos , Compuestos de Bifenilo/química , Fibroblastos/efectos de los fármacos , Tecnología Química Verde , Células HeLa , Humanos , Peroxidación de Lípido/efectos de los fármacos , Masculino , Nanopartículas del Metal/ultraestructura , Pruebas de Sensibilidad Microbiana , Picratos/química , Espectrometría por Rayos X , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Difracción de Rayos X
3.
Int J Nanomedicine ; 16: 1901-1911, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33707945

RESUMEN

Purpose: Developing a sensitive SERS-based method to quantitatively detect serum biomarkers (Aß1-42 and P-Tau-181) for the early diagnosis of Alzheimer's disease (AD). Methods: In this study, a novel SERS-based sandwich immunoassay, which consists of tannin-capped silver nanoparticles and magnetic graphene oxide (Fe3O4@GOs), was developed. We firstly applied this method for the detection of protein standards in buffer solution, obtaining the regression equation. Then, its potential value on real serum samples of AD was further explored. Results: The detection linear range of Aß1-42 and P-Tau-181 protein standards were observed to range from 100 pg mL-1 to 10 fg mL-1, 100 pg mL-1 to 1 fg mL-1 respectively. We finally explored clinical application of the proposed method in 63 serum samples. As a result, P-tau-181 differentiated AD from non-AD dementia patients (AUC = 0.770), with a more favored ROC than Aß1-42 (AUC = 0.383). Conclusion: The developed SERS-based immunoassay is successfully applied to the determination of Aß1-42 and P-Tau-181 in human serum specimens, which provides a promising tool for the early diagnosis of AD.


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Biomarcadores/sangre , Inmunoensayo/métodos , Sondas Moleculares/química , Plata/química , Espectrometría Raman/métodos , Péptidos beta-Amiloides/sangre , Benzoatos/química , Calibración , Femenino , Grafito/química , Humanos , Límite de Detección , Masculino , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Compuestos de Sulfhidrilo/química , Difracción de Rayos X , Proteínas tau/sangre
4.
Int J Nanomedicine ; 16: 1993-2011, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727811

RESUMEN

Background: Even with considerable improvement in treatment of epithelial ovarian cancer achieved in recent years, an increasing chemotherapy resistance and disease 5-year relapse is recorded for a majority part of patients that encourages the search for better therapeutic options. Gold nanoparticles (Au NPs) due to plethora of unique physiochemical features are thoroughly tested as drug delivery, radiosensitizers, as well as photothermal and photodynamic therapy agents. Importantly, due to highly controlled synthesis, it is possible to obtain nanomaterials with directed size and shape. Methods: In this work, we developed novel elongated-type gold nanoparticles in the shape of nanopeanuts (AuP NPs) and investigated their cytotoxic potential against ovarian cancer cells SKOV-3 using colorimetric and fluorimetric methods, Western blot, flow cytometry, and fluorescence microscopy. Results: Peanut-shaped gold nanoparticles showed high anti-cancer activity in vitro against SKOV-3 cells at doses of 1-5 ng/mL upon 72 hours treatment. We demonstrate that AuP NPs decrease the viability and proliferation capability of ovarian cancer cells by triggering cell apoptosis and autophagy, as evidenced by flow cytometry and Western blot analyses. The overproduction of reactive oxygen species (ROS) was noted to be a critical mediator of AuP NPs-mediated cell death. Conclusion: These data indicate that gold nanopeanuts might be developed as nanotherapeutics against ovarian cancer.


Asunto(s)
Apoptosis , Autofagia , Oro/química , Nanopartículas del Metal/química , Neoplasias Ováricas/patología , Especies Reactivas de Oxígeno/metabolismo , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Arachis , Autofagia/efectos de los fármacos , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/ultraestructura , Neoplasias Ováricas/tratamiento farmacológico , Oxidación-Reducción
5.
Int J Nanomedicine ; 16: 2059-2070, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727813

RESUMEN

Purpose: The purpose of this study was to establish a lateral flow immunoassay using selenium nanoparticles (Se-NPs) as a probe to detect ractopamine (RAC) and salbutamol (SAL) in swine urine. Methods: SDS and PEG were used as templates to prepare Se-NPs; anti-RAC monoclonal antibodies or anti-SAL monoclonal antibodies were labelled with Se-NPs; and rapid detection kits were prepared. The sensitivity, specificity, and stability were measured, and actual samples were analysed. Results: The Se-NPs were spherical with a diameter of 40.63 ± 5.91 nm, and were conjugated successfully with an anti-RAC antibody to give a total diameter of 82.33 ± 17.91 nm. The detection limit of a RAC kit in swine urine was 1 ng/mL, and that of a SAL kit was 3 ng/mL. Both procedures could be completed within 5 minutes. No cross-reaction occurred with clenbuterol, bambuterol and phenylethanolamine A. Samples were tested consistently across different batches of kits for swine urine. The results of the kits were identical to those of actual clinical samples analysed by ELISA, and the coincidence rate was 100%. Conclusion: The assay kit does not require any special device for reading the results, and the readout is a simple colour change that can be evaluated with the naked eye. It is easy to operate, sensitive, specific, and stable This kit is suitable for the rapid and real-time detection of RAC and SAL residues in swine urine samples. Clinical Trial Registration: Swine urines samples were used under approval from the Experimental Animal Ethics committee of the Joint National Laboratory for Antibody Drug Engineering, Henan University.


Asunto(s)
Albuterol/orina , Cromatografía de Afinidad/métodos , Nanopartículas del Metal/química , Fenetilaminas/orina , Selenio/química , Animales , Anticuerpos/metabolismo , Concentración de Iones de Hidrógeno , Porcinos
6.
Int J Nanomedicine ; 16: 2071-2085, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727814

RESUMEN

Background: Radiation therapy remains an important treatment modality in cancer therapy, however, resistance is a major problem for treatment failure. Elevated expression of glutathione is known to associate with radiation resistance. We used glutathione overexpressing small cell lung cancer cell lines, SR3A-13 and SR3A-14, established by transfection with γ-glutamylcysteine synthetase (γ-GCS) cDNA, as a model for investigating strategies of overcoming radiation resistance. These radiation-resistant cells exhibit upregulated human copper transporter 1 (hCtr1), which also transports cisplatin. This study was initiated to investigate the effect and the underlying mechanism of iron-platinum nanoparticles (FePt NPs) on radiation sensitization in cancer cells. Materials and Methods: Uptakes of FePt NPs in these cells were studied by plasma optical emission spectrometry and transmission electron microscopy. Effects of the combination of FePt NPs and ionizing radiation were investigated by colony formation assay and animal experiment. Intracellular reactive oxygen species (ROS) were assessed by using fluorescent probes and imaged by a fluorescence-activated-cell-sorting caliber flow cytometer. Oxygen consumption rate (OCR) in mitochondria after FePt NP and IR treatment was investigated by a Seahorse XF24 cell energy metabolism analyzer. Results: These hCtr1-overexpressing cells exhibited elevated resistance to IR and the resistance could be overcome by FePt NPs via enhanced uptake of FePt NPs. Overexpression of hCtr1 was responsible for the increased uptake/transport of FePt NPs as demonstrated by using hCtr1-transfected parental SR3A (SR3A-hCtr1-WT) cells. Increased ROS and drastic mitochondrial damages with substantial reduction of oxygen consumption rate were observed in FePt NPs and IR-treated cells, indicating that structural and functional insults of mitochondria are the lethal mechanism of FePt NPs. Furthermore, FePt NPs also increased the efficacy of radiotherapy in mice bearing SR3A-hCtr1-WT-xenograft tumors. Conclusion: These results suggest that FePt NPs can potentially be a novel strategy to improve radiotherapeutic efficacy in hCtr1-overexpressing cancer cells via enhanced uptake and mitochondria targeting.


Asunto(s)
Aleaciones/farmacología , Transportador de Cobre 1/metabolismo , Hierro/farmacología , Nanopartículas del Metal/química , Mitocondrias/metabolismo , Neoplasias/metabolismo , Platino (Metal)/farmacología , Tolerancia a Radiación , Aerobiosis , Animales , Línea Celular Tumoral , Respiración de la Célula/efectos de los fármacos , Glutatión/metabolismo , Humanos , Nanopartículas del Metal/ultraestructura , Ratones SCID , Mitocondrias/efectos de los fármacos , Mitocondrias/ultraestructura , Modelos Biológicos , Tolerancia a Radiación/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Resultado del Tratamiento , Rayos X
7.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652788

RESUMEN

Molybdates are biocidal materials that can be useful in coating surfaces that are susceptible to contamination and the spread of microorganisms. The aim of this work was to investigate the effects of copper doping of hydrated cobalt molybdate, synthesized by the co-precipitation method, on its antibacterial activity and to elucidate the structural and morphological changes caused by the dopant in the material. The synthesized materials were characterized by PXRD, Fourier Transformed Infrared (FTIR), thermogravimetric analysis/differential scanning calorimetry (TG/DSC), and SEM-Energy Dispersive Spectroscopy (SEM-EDS). The antibacterial response of the materials was verified using the Minimum Inhibitory Concentration (MIC) employing the broth microdilution method. The size of the CoMoO4·1.03H2O microparticles gradually increased as the percentage of copper increased, decreasing the energy that is needed to promote the transition from the hydrated to the beta phase and changing the color of material. CoMoO4·1.03H2O obtained better bactericidal performance against the tested strains of Staphylococcus aureus (gram-positive) than Escherichia coli (gram-negative). However, an interesting point was that the use of copper as a doping agent for hydrated cobalt molybdate caused an increase of MIC value in the presence of E. coli and S. aureus strains. The study demonstrates the need for caution in the use of copper as a doping material in biocidal matrices, such as cobalt molybdate.


Asunto(s)
Antiinfecciosos/química , Cobalto/química , Cobre/química , Molibdeno/química , Antiinfecciosos/farmacología , Infecciones Bacterianas/tratamiento farmacológico , Complejos de Coordinación/química , Escherichia coli/efectos de los fármacos , Humanos , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Tamaño de la Partícula , Staphylococcus aureus/efectos de los fármacos
8.
J Vis Exp ; (168)2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33645589

RESUMEN

Kidney stones are becoming more prevalent worldwide in adults and children. The most common type of kidney stone is comprised of calcium oxalate (CaOx) crystals. Crystalluria occurs when urine becomes supersaturated with minerals (e.g., calcium, oxalate, phosphate) and precedes kidney stone formation. Standard methods to assess crystalluria in stone formers include microscopy, filtration, and centrifugation. However, these methods primarily detect microcrystals and not nanocrystals. Nanocrystals have been suggested to be more harmful to kidney epithelial cells than microcrystals in vitro. Here, we describe the ability of Nanoparticle Tracking analysis (NTA) to detect human urinary nanocrystals. Healthy adults were fed a controlled oxalate diet prior to drinking an oxalate load to stimulate urinary nanocrystals. Urine was collected for 24 hours before and after the oxalate load. Samples were processed and washed with ethanol to purify samples. Urinary nanocrystals were stained with the calcium binding fluorophore, Fluo-4 AM. After staining, the size and count of nanocrystals were determined using NTA. The findings from this study show NTA can efficiently detect nanocrystalluria in healthy adults. These findings suggest NTA could be a valuable early detection method of nanocrystalluria in patients with kidney stone disease.


Asunto(s)
Compuestos de Anilina/química , Oxalato de Calcio/orina , Oro/química , Nanopartículas del Metal/química , Nanopartículas/química , Xantenos/química , Adulto , Humanos
9.
Anal Chim Acta ; 1154: 338330, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33736792

RESUMEN

The recent outbreak of coronavirus disease 2019 (COVID-19) is highly infectious, which threatens human health and has received increasing attention. So far, there is no specific drug or vaccine for COVID-19. Therefore, it is urgent to establish a rapid and sensitive early diagnosis platform, which is of great significance for physical separation of infected persons after rapid diagnosis. Here, we propose a colorimetric/SERS/fluorescence triple-mode biosensor based on AuNPs for the fast selective detection of viral RNA in 40 min. AuNPs with average size of 17 nm were synthesized, and colorimetric, surface enhanced Raman scattering (SERS), and fluorescence signals of sensors are simultaneously detected based on their basic aggregation property and affinity energy to different bio-molecules. The sensor achieves a limit detection of femtomole level in all triple modes, which is 160 fM in absorbance mode, 259 fM in fluorescence mode, and 395 fM in SERS mode. The triple-mode signals of the sensor are verified with each other to make the experimental results more accurate, and the capacity to recognize single-base mismatch in each working mode minimizes the false negative/positive reading of SARS-CoV-2. The proposed sensing platform provides a new way for the fast, sensitive, and selective detection of COVID-19 and other diseases.


Asunto(s)
Técnicas Biosensibles/métodos , Nanopartículas del Metal/química , ARN Viral/análisis , /genética , /virología , Oro/química , Humanos , Límite de Detección , Tamaño de la Partícula , ARN Viral/química , Espectrometría Raman , Glicoproteína de la Espiga del Coronavirus/genética
10.
J Vis Exp ; (168)2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33682852

RESUMEN

Temperature control is a recent development that provides an additional degree of freedom to study nanochemistry by liquid cell transmission electron microscopy. In this paper, we describe how to prepare an in situ heating experiment for studying the effect of temperature on the formation of gold nanoparticles driven by radiolysis in water. The protocol of the experiment is fairly simple involving a special liquid cell with uniform heating capabilities up to 100 °C, a liquid-cell TEM holder with flow capabilities and an integrated interface for controlling the temperature. We show that the nucleation and growth mechanisms of gold nanoparticles are drastically impacted by the temperature in liquid cell. Using STEM imaging and nanodiffraction, the evolution of the density, size, shape and atomic structure of the growing nanoparticles are revealed in real time. Automated image processing algorithms are exploited to extract useful quantitative data from video sequences, such as the nucleation and growth rates of nanoparticles. This approach provides new inputs for understanding the complex physico-chemical processes at play during the liquid-phase synthesis of nanomaterials.


Asunto(s)
Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Transmisión , Temperatura , Oro/química , Calefacción , Procesamiento de Imagen Asistido por Computador , Programas Informáticos , Agua/química
11.
Carbohydr Polym ; 260: 117835, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712172

RESUMEN

Bacterial breeding is the main cause of food perishability, which is harmful to human health. Silver nanoparticles (AgNPs) are one of the most widely used antimicrobial agents, but they are easy to release and cause cumulative toxicity. In this work, with corn stalk as green reductant and GO as template, a simple electrostatic self-assembled sandwich-like chitosan (CS) wrapped rGO@AgNPs nanocomposite film (CS/rGO@AgNPs) was synthesized to achieve stabilizing and controlled-release of AgNPs. The results showed that the the CS/rGO@AgNPs film continued releasing AgNPs for up to 14 days, and the final release amount of silver nanoparticles was only about 1.9 %. More importantly, the nanocomposite film showed durable antibacterial effect and good antibacterial activity against E. coli and S. aureus, and they showed no toxicity to cells. Hence, the nanocomposite film has potential application as an effective and safe packaging material to prolong the shelf life of food products.


Asunto(s)
Antibacterianos/química , Quitosano/química , Grafito/química , Nanopartículas del Metal/química , Nanocompuestos/química , Antibacterianos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Escherichia coli/efectos de los fármacos , Humanos , Nanocompuestos/toxicidad , Plata/química , Solubilidad , Staphylococcus aureus/efectos de los fármacos , Resistencia a la Tracción
12.
Carbohydr Polym ; 260: 117840, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712175

RESUMEN

Highly efficient shielding materials with an excellent electromagnetic wave absorption have gained increased attention. A new design was used to provide cellulose paper with a high electromagnetic shielding effectiveness (EMI SE) and improve the absorption performance by constructing an asymmetry sandwich structure that consisted of a dense nickel coating, Fe3O4 nanoparticles and a porous nickel layer. This unique structure caused a "multiple reflection-absorb-reflection" process when the electromagnetic waves penetrated the sample. The EMI absorption (SEA) and total SE (SET) increased with Fe3O4 absorption time increasing at 8.2-12.4 GHz, which was attributed to the synergistic effect between porous nickel layer and Fe3O4 nanoparticles. The SEA and SET of the sample with a thickness of 0.195 mm can achieved 18.57 and 41.88 dB, respectively. The design was conducive to improving the magnetic and corrosion resistance properties. This study provided a novel path to obtain a low cost and lightweight electromagnetic shielding material that can reduce secondary radiation.


Asunto(s)
Celulosa/química , Óxido Ferrosoférrico/química , Níquel/química , Protectores contra Radiación/química , Conductividad Eléctrica , Campos Electromagnéticos , Magnetismo , Nanopartículas del Metal/química , Porosidad , Propiedades de Superficie , Temperatura
13.
Molecules ; 26(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33668968

RESUMEN

The unique chemical, optical, and electrical characteristics of nanoparticles make their utilization highly successful in every field of biological sciences as compared to their bulk counterpart. These properties arise as a result of their miniature size, which provides them an excellent surface area-to-volume ratio, inner structure, and shape, and hence increases their surface characteristics. Therefore, this study was undertaken to engineer gold nanoparticles (AuNPs) for improving their catalytic activity and stability in biotechnological processes. The characterization of AuNPs was performed by XRD, UV spectra, and TEM. The synthesized AuNPs were surface-modified by polyvinyl alcohol (PVA) for binding the enzyme in excellent yield. The developed immobilized enzyme system (PVA-AuNPs-ß-galactosidase) displayed pH optima at pH 7.0 and temperature optima at 40 °C. Moreover, the stability of PVA-AuNPs-ß-galactosidase was significantly enhanced at wider pH and temperature ranges and at higher galactose concentrations, in contrast to the free enzyme. ß-galactosidase bound to PVA-modified AuNPs exhibited greater operational activity, even after its sixth reuse. The developed nanosystem may prove useful in producing lactose-free dairy products for lactose-intolerant patients.


Asunto(s)
Productos Lácteos , Oro/química , Lactosa/química , Nanopartículas del Metal/química , beta-Galactosidasa/química , Productos Lácteos/análisis , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Oro/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Kluyveromyces/enzimología , Lactosa/metabolismo , Intolerancia a la Lactosa/metabolismo , Prueba de Tolerancia a la Lactosa , Tamaño de la Partícula , Propiedades de Superficie , Temperatura , beta-Galactosidasa/metabolismo
14.
Food Chem ; 352: 129327, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690077

RESUMEN

This paper describes a voltammetric method and data analysis program developed for the detection of arsenic(III) in commercial apple juice. Arsenic(III) was detected using square wave stripping voltammetry with gold nanoparticle modified screen printed electrodes. The only sample pretreatment performed was the addition of a 100 mM phosphate buffer with a pH of 7. To compensate for interference from high ascorbic acid concentrations, a data analysis program was developed in MATLAB to fit a non-linear baseline, allowing for accurate peak height measurement. With this data analysis program, the developed methodology had a sensitivity of 0.1007 µA (µg L-1)-1 and a limit of detection of 16.73 µg L-1. A comparison between the voltammetric method and graphite furnace atomic absorption spectroscopy showed no bias in the voltammetric results and a good correlation between the two sets of predicted concentrations, with an R2 of 0.939.


Asunto(s)
Arsénico/análisis , Carbono/química , Electroquímica/instrumentación , Jugos de Frutas y Vegetales/análisis , Oro/química , Malus/química , Nanopartículas del Metal/química , Electrodos , Análisis de los Alimentos/instrumentación , Impresión , Factores de Tiempo
15.
Carbohydr Polym ; 260: 117772, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712130

RESUMEN

Nanoparticle-polymer composites are important functional materials but structural control of their assembly is challenging. Owing to its crystalline internal structure and tunable nanoscale morphology, cellulose is promising polymer scaffold for templating such composite materials. Here, we show bottom-up synthesis of reducing end thiol-modified cellulose chains by iterative bi-enzymatic ß-1,4-glycosylation of 1-thio-ß-d-glucose (10 mM), to a degree of polymerization of ∼8 and in a yield of ∼41% on the donor substrate (α-d-glucose 1-phosphate, 100 mM). Synthetic cellulose oligomers self-assemble into highly ordered crystalline (cellulose allomorph II) material showing long (micrometers) and thin nanosheet-like morphologies, with thickness of 5-7 nm. Silver nanoparticles were attached selectively and well dispersed on the surface of the thiol-modified cellulose, in excellent yield (≥ 95%) and high loading efficiency (∼2.2 g silver/g thiol-cellulose). Examined against Escherichia coli and Staphylococcus aureus, surface-patterned nanoparticles show excellent biocidal activity. Bottom-up approach by chemical design to a functional cellulose nanocomposite is presented. Synthetic thiol-containing nanocellulose can expand the scope of top-down produced cellulose materials.


Asunto(s)
Antibacterianos/química , Celulosa/química , Nanopartículas del Metal/química , Nanocompuestos/química , Compuestos de Sulfhidrilo/química , Antibacterianos/farmacología , Pruebas Antimicrobianas de Difusión por Disco , Escherichia coli/efectos de los fármacos , Nanocompuestos/toxicidad , Plata/química , Staphylococcus aureus/efectos de los fármacos
16.
ACS Sens ; 6(3): 613-627, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33660987

RESUMEN

Viruses have caused significant damage to the world. Effective detection is required to relieve the impact of viral infections. A biomolecule can be used as a template such as deoxyribonucleic acid (DNA), peptide, or protein, for the growth of silver nanoclusters (AgNCs) and for recognizing a virus. Both the AgNCs and the recognition elements are tunable, which is promising for the analysis of new viruses. Considering that a new virus such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) urgently requires a facile sensing strategy, various virus detection strategies based on AgNCs including fluorescence enhancement, color change, quenching, and recovery are summarized. Particular emphasis is placed on the molecular analysis of viruses using DNA stabilized AgNCs (DNA-AgNCs), which detect the virus's genetic material. The more widespread applications of AgNCs for general virus detection are also discussed. Further development of these technologies may address the challenge for facile detection of SARS-CoV-2.


Asunto(s)
Técnicas Biosensibles , ADN Viral/química , Nanopartículas del Metal/química , Plata/química , Virus/genética , Fluorescencia , Humanos
17.
Molecules ; 26(4)2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33672102

RESUMEN

Macroalgae are sources of bioactive compounds that are interesting from both a chemical and a medical point of view. Although their use in biomedicine has increased significantly in recent years, tests conducted to date have been mostly related to species from temperate latitudes, with the potential application of Antarctic biodiversity being minor. The wide variety of algae species present on Antarctic coastal areas can be a source of new antioxidants. Bearing this in mind, the brown macroalgae Desmarestia antarctica (DA) and the red Iridaea cordata (IC) were selected for the preparation of aqueous extracts with the aim of analyzing their antioxidant activity. This analysis was performed by determining reducing power, total phenolic content, and 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity. Furthermore, both extracts were employed to synthesize gold and silver nanoparticles. The nanomaterials were fully characterized by means of UV-Visible spectroscopy, transmission electron microscopy, Z potential measurements, and Fourier transform infrared spectroscopy, which confirmed the formation of stable, spherical nanoparticles with mean diameters of 13.7 ± 3.1 and 17.5 ± 3.7 nm for Ag@DA and Ag@IC and 12.6 ± 1.9 and 12.3 ± 1.6 nm for Au@DA and Au@IC. Antioxidant assays were performed after the synthesis of the nanomaterials to evaluate their possible synergistic effect with the extracts. The results suggest that polysaccharides and proteins may play a key role in the process of reduction and stabilization. Finally, for the sake of comparison, the results obtained for the Antarctic macroalgae Desmarestia menziesii and Palmaria decipiens have also been considered in the present work.


Asunto(s)
Antioxidantes/farmacología , Oro/metabolismo , Nanopartículas del Metal/química , Phaeophyta/química , Rhodophyta/química , Plata/metabolismo , Regiones Antárticas , Antioxidantes/síntesis química , Antioxidantes/química , Compuestos de Bifenilo/antagonistas & inhibidores , Oro/química , Tamaño de la Partícula , Picratos/antagonistas & inhibidores , Plata/química
18.
Food Chem ; 352: 129354, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33677209

RESUMEN

Biosensors have been widely applied in tests for allergens, but on-site detection remains a challenge. Herein, we proposed a detection procedure for peanut Ara h 1 as a representative allergen, which was extracted from a cookie, thereby minimising the need for any complex pretreatment that was difficult to perform, and enabling the visual detection of the target without the use of analytical equipment. The extraction procedure was performed in less than 30 min using a syringe and filter (0.45 µm). The detection method for Ara h 1 was based on the aggregation of switchable linkers (SL) and gold nanoparticles (AuNP), and the presence of 0.19 mg peanut protein per 30 g of cookie could be confirmed within 30 min based on the AuNP/SL concentration ratio by the precipitation. This proposed procedure could be successfully applied to the detection of a wide range of food allergens.


Asunto(s)
Antígenos de Plantas/análisis , Antígenos de Plantas/aislamiento & purificación , Precipitación Química , Oro/química , Proteínas de la Membrana/análisis , Proteínas de la Membrana/aislamiento & purificación , Nanopartículas del Metal/química , Proteínas de Plantas/análisis , Proteínas de Plantas/aislamiento & purificación , Antígenos de Plantas/inmunología , Humanos , Proteínas de la Membrana/inmunología , Hipersensibilidad al Cacahuete , Proteínas de Plantas/inmunología
19.
ACS Sens ; 6(3): 1086-1093, 2021 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-33683104

RESUMEN

The outbreak of COVID-19 caused a worldwide public health crisis. Large-scale population screening is an effective means to control the spread of COVID-19. Reverse transcription-polymerase chain reaction (RT-qPCR) and serology assays are the most available techniques for SARS-CoV-2 detection; however, they suffer from either less sensitivity and accuracy or low instrument accessibility for screening. To balance the sensitivity, specificity, and test availability, here, we developed enhanced colorimetry, which is termed as a magnetic pull-down-assisted colorimetric method based on the CRISPR/Cas12a system (M-CDC), for SARS-CoV-2 detection. By this method, SARS-CoV-2 RNA from synthetic sequences and cultured viruses can be detected by the naked eye based on gold nanoparticle (AuNP) probes, with a detection limit of 50 RNA copies per reaction. With CRISPR/Cas12a-assisted detection, SARS-CoV-2 can be specifically distinguished from other closely related viruses. M-CDC was further used to analyze 41 clinical samples, whose performance was 95.12%, consistent with that of an approved Clinical RT-qPCR Diagnosis kit. The developed M-CDC method is not dependent on sophisticated instruments, which makes it potentially valuable to be applied for SARS-CoV-2 screening under poor conditions.


Asunto(s)
/métodos , ARN Viral/análisis , /genética , Proteínas Bacterianas , Proteínas Asociadas a CRISPR , Sistemas CRISPR-Cas , Línea Celular Tumoral , Colorimetría , ADN/química , Sondas de ADN , Endodesoxirribonucleasas , Oro/química , Humanos , Nanopartículas del Metal/química
20.
AAPS PharmSciTech ; 22(2): 64, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33533992

RESUMEN

The aim of the study was to prepare 5-fluorouracil (5-FU)-loaded biogenic gold nanoparticles with pluronic-based coating (PFGNPs), their optimization (full factorial predicted OBPN-1) and in vitro-ex vivo evaluation. Several formulations were prepared, selected for optimization using Design Expert®, and compared for morphology, 5-FU release kinetics, compatibility, cell line toxicity, in vitro hemocompatibility, and ex vivo intestinal permeation across the rat duodenum, jejunum, and ileum. The pluronic-coated 5-FU-carrying GNPs were spherical, 29.11-178.21 nm in diameter, with a polydispersity index (PDI) range of 0.191-292, and a zeta potential (ZP) range of 11.19-29.21 (-mV). The optimized OBPN-1 (desirability = 0.95) demonstrated optimum size (175.1 nm), %DL as 73.8%, ZP as 21.7 mV, % drug release (DR) as 75.7%, and greater cytotoxicity (viability ~ 8.9%) against the colon cancer cell lines than 5-FU solution (~ 24.91%), and less hemocompatibility. Moreover, OBPN-1 exhibited 4.5-fold permeation across the rat jejunum compared with 5-FU solution. Thus, the PFGNPs exhibit high DL capacity, sustained delivery, hemocompatibility, improved efficacy, and enhanced permeation profiles compared with 5-FU solution and several other NPs preparations suggesting it is a promising formulation for effective colon cancer control with reduced side effects.


Asunto(s)
Neoplasias del Colon/tratamiento farmacológico , Fluorouracilo/administración & dosificación , Oro/química , Nanopartículas del Metal/química , Animales , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Fluorouracilo/química , Humanos , Ratas , Células Tumorales Cultivadas
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