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1.
J Photochem Photobiol B ; 204: 111767, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32006893

RESUMEN

Colon carcinoma is a recurring type of cancer that affects the intestine epithelial with a poor survival rate. It was already proven the anticancer property of hesperidin in various cancers but the bioavailability hesperidin is poor, which hinders the hesperidin usage. In this investigation we synthesized hesperidin loaded Zn2+@ SA/PCT nanocomposites and assessed its anticancer potential against colon cancer (HCT116) cells. Hesperidin loaded Zn2+@ SA/PCT nanocomposites were characterized using Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis. The drug releasing capacity and cytotoxic property was assessed via drug releasing assay, MTT assay with HCT116 cells. The anticancer potency of hesperidin nanocomposites were evaluated with TUNEL, DAPI staining, reactive oxygen species (ROS) generation assay and it is confirmed with flow cytometry analysis of MMP disruption in colon cancer (HCT116) cell line. Further the immunoblotting analysis of cysteine proteases Caspases 3, 9, PARP, proapoptotic protein Bax and antiapoptotic protein Bcl2 were performed. The results of FTIR, XRD and electroscopic analyses confirmed the synthesized hesperidin nanocomposites accomplish the properties of potent nanodrug and the MTT assay authentically confirmed that the synthesized hesperidin nanocomposite inhibited the HCT116 cell growth, and the results of fluorescent staining proved that the hesperidin nanocomposite induced the apoptotic mediated cell necrosis via promoting the expression of apoptotic proteins thereby induced the apoptosis in colon cancer (HCT116) cells. Hence, it was concluded that the, hesperidin loaded nanocomposites persuasively inhibited proliferation of colon carcinoma cell and induced apoptosis in in vitro condition.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Proliferación Celular/efectos de los fármacos , Hesperidina/química , Nanocompuestos/química , Alginatos/química , Antineoplásicos Fitogénicos/química , Caspasa 3/metabolismo , Supervivencia Celular/efectos de los fármacos , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Composición de Medicamentos , Liberación de Fármacos , Células HCT116 , Hesperidina/farmacología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Pectinas/química , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Zinc/química
2.
Chemosphere ; 244: 125577, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32050350

RESUMEN

Persulfate based advanced oxidation process is a promising technology for refractory contaminants removal. Cobalt is considered as the most efficient metal in catalyzing peroxymonosulfate decomposition. Although different cobalt based nanomaterials have been developed, easy aggregation and metal ion leaching during catalytic reaction would result in its deficiency. To address the above issue, in this work, carbon supported Co/CoO core-shell nanocomposite was in-situ fabricated by using polyphenol-metal coordinate as precursor. Results indicated that cobalt nanoparticle with size of 10 nm was successfully prepared and well dispersed within the carbon matrix. By using as-prepared material as catalyst, 50 mg/L orange II was completely removed under the condition of 0.2 g/L peroxymonosulfate, 0.05 g/L catalyst, pH = 4.0-10.0. Both sulfate and hydroxyl radicals were formed during peroxymonosulfate decomposition, while sulfate radical dominated the pollutant removal. Mechanism study revealed that the cobalt was the key site for catalyzing peroxymonosulfate decomposition. This work might provide valuable information in designing and fabricating metal anchored carbon composite catalyst for efficiently and cost-effectively activate peroxymonosulfate.


Asunto(s)
Colorantes/química , Nanocompuestos/química , Peróxidos/química , Compuestos Azo , Bencenosulfonatos , Carbono/química , Catálisis , Cobalto/química , Modelos Químicos , Oxidación-Reducción , Sulfatos
3.
J Photochem Photobiol B ; 203: 111774, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31931386

RESUMEN

Zeolitic imidazole framework (ZIF) is an emerging class of metal organic frameworks exhibiting unique features such as crystalline nature with tunable pore size, large surface area and biocompatible nature. Exceptional thermal and chemical stabilities of ZIF-L make it a suitable candidate for biomedical applications. The present study has focused on the single step fabrication of catechin encapsulated ZIF-L and evaluation of its antibiofilm efficiency, larvicidal activity and dye degradation ability. The as- prepared CA@ZIF-L nanocomposite was characterized by spectroscopic and microscopic techniques. The results revealed that the CA@ZIF-L showed significant toxicity against mosquito larvae in a dose dependent manner with the IC50 63.43±1.25 µg/mL. CA@ZIF-L showed dose dependent reduction of biofilm formation in both ATCC and clinical MRSA strains. In addition, CA@ZIF-L exhibited excellent photocatalytic activity with around 92% degradation of methylene blue under direct sunlight. Overall, the present work highlights the possibility of employing the multifunctional CA@ZIF-L nanocomposite as a suitable material for biomedical and photocatalytic applications.


Asunto(s)
Biopelículas/efectos de los fármacos , Catequina/química , Estructuras Metalorgánicas/química , Nanocompuestos/toxicidad , Zeolitas/química , Animales , Catálisis , Culicidae/efectos de los fármacos , Culicidae/crecimiento & desarrollo , Imidazoles/química , Larva/efectos de los fármacos , Luz , Staphylococcus aureus Resistente a Meticilina/fisiología , Azul de Metileno/química , Nanocompuestos/química , Tamaño de la Partícula , Fotólisis/efectos de la radiación
4.
J Photochem Photobiol B ; 204: 111783, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31954265

RESUMEN

Cadmium sulfide-graphitic carbon nitride nanocomposite was synthesized by pulsed laser ablation in liquid, and it was found from the results of optical and morphological characterizations that the proper anchoring of nanostructured cadmium sulfide on the nano-sheets of graphitic carbon nitride took place, which brought about the positive attributes such as enhanced visible light absorption and reduced photo-generated charge recombination, the key features required for an efficient photo-catalyst by solar light harvesting. The pulsed laser ablation in liquid method adopted for the synthesis of cadmium sulfide-graphitic carbon nitride has the following advantages: the shape and size of the synthesized particles can be controlled by altering the experimental parameters such as laser wavelength, pulse laser duration, the pH of the solution, the surfactants and the temperature of the solution, pulsed laser ablation in liquid method neither requires cumbersome equipment nor does it require intermediate chemicals and catalysts nor does it necessitate the post synthesis purification. The enhancement of photo-catalytic activity of cadmium sulfide-graphitic carbon nitride nanocomposite was tested for the photo-catalytic deactivation of Escherichia coli bacteria in water under visible light radiation. As anticipated, a significant improvement of photo-catalytic deactivation was observed, which is attributed to the enhanced and extended light absorption in the visible spectral region, and the formation of herterojunction between the semiconductors, which is instrumental in inhibiting the undesired recombination of photo-generated charge carriers. Quantitatively, the presence of cadmium sulfide on the graphitic carbon nitride surface contributed to a remarkable 129% increase of photo-catalytic degradation constant compared to pure graphitic carbon nitride, which resulted in the decrease of total depletion time of Escherichia coli from 156 min to 67 min with the cadmium sulfide-graphitic carbon nitride nanocomposite synthesized by pulsed laser ablation in liquid method. Our results on the efficient photo-catalytic deactivation of Escherichia coli under visible light assures that cadmium sulfide-graphitic carbon nitride nanocomposite can very well be used for photo-catalytic water purification by harvesting the abundant solar light.


Asunto(s)
Compuestos de Cadmio/química , Grafito/química , Luz , Nanocompuestos/química , Compuestos de Nitrógeno/química , Sulfuros/química , Purificación del Agua/métodos , Catálisis , Escherichia coli/efectos de los fármacos , Nanocompuestos/toxicidad , Estudios Prospectivos
5.
Chem Commun (Camb) ; 56(11): 1717-1720, 2020 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-31942593

RESUMEN

A novel sensor array based on a (+)AuNP/AuNC nanocomposite was constructed for the selective discrimination of 10 types of Gram-negative bacteria (including 3 types of antibiotic-resistant strains) at a low concentration level of OD600 = 0.015. By recognizing the triple optical patterns of Gram-negative bacteria with the assistance of LDA, the sensor array is able to group the bacteria with respect to their species to each other.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Bacterias Gramnegativas/aislamiento & purificación , Nanopartículas del Metal/química , Análisis por Conglomerados , Análisis Discriminante , Oro/química , Bacterias Gramnegativas/clasificación , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/aislamiento & purificación , Humanos , Nanocompuestos/química , Dispersión de Radiación , Espectrometría de Fluorescencia , Orina/microbiología , Vancomicina/química
6.
J Nanobiotechnology ; 18(1): 17, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31964393

RESUMEN

This study aimed to develop a new colon-targeted drug delivery system via the preparation of ternary nanocomposite carriers based on organic polymer, aminoclay and lipid vesicles. Budesonide (Bud), an anti-inflammatory drug was chosen as a model drug and encapsulated into three different formulations: liposome (Bud-Lip), aminoclay-coated liposome (AC-Bud-Lip), and Eudragit® S100-aminoclay double coated liposome (EAC-Bud-Lip). The formation of the aminoclay-lipid vesicle nanocomposite was confirmed by energy dispersive X-ray spectrum, transmission electron microscopy, and Fourier-transform infrared spectroscopy. All formulations were produced with a high encapsulation efficiency in a narrow size distribution. Drug release from EAC-Bud-Lip was approximately 10% for 2-h incubation at pH 1.2, implying the minimal drug release in acidic gastric condition. At pH 7.4, EAC-Bud-Lip underwent significant size reduction and exhibited drug release profiles similar to that from AC-Bud-Lip, implying the pH-dependent removal of the outer coating layer. Compared to free Bud solution, EAC-Bud-Lip achieved a higher drug uptake in Caco-2 cells and exhibited a stronger inhibition of TNF-α and IL-6 secretion in LPS-stimulated Raw264.7 cells. Furthermore, a bio-distribution study in mice demonstrated that Eudragit® S100-aminoclay dual coating led to a higher colonic distribution with a longer residence time, which correlated well with the delayed systemic drug exposure in rats. Taken together, the present study suggests that the ternary nanocomposite carrier consisting of Eudragit® S100, aminoclay, and lipid vesicle might be useful as an effective colon-targeted drug delivery system.


Asunto(s)
Antiinflamatorios/química , Budesonida/química , Arcilla/química , Colon/metabolismo , Lípidos/química , Liposomas/química , Nanocompuestos/química , Animales , Antiinflamatorios/farmacocinética , Budesonida/farmacocinética , Células CACO-2 , Liberación de Fármacos , Humanos , Concentración de Iones de Hidrógeno , Interleucina-6/metabolismo , Masculino , Ratones , Ácidos Polimetacrílicos/química , Células RAW 264.7 , Ratas Sprague-Dawley , Solubilidad , Propiedades de Superficie , Distribución Tisular , Factor de Necrosis Tumoral alfa/metabolismo
7.
Anal Bioanal Chem ; 412(1): 193-201, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31760449

RESUMEN

A highly sensitive approach to detect trace amount of clenbuterol (CB) based on graphene oxide/gold nanoparticles (GO/Au NPs) by surface-enhanced Raman spectroscopy (SERS) was presented. To be specific, the GO/Au nanocomposites were formed by depositing Au NPs onto the surface of GO through an in situ reduction process, where a high density of inherent hot spots was created between Au NPs. By optimizing the depositing density of Au NPs, the strongest electromagnetic coupling effect originating from highly dense hot spots was obtained. The optimized GO/Au was demonstrated to enhance the Raman signals of CB by 4.8 times more than that of CB enhanced by Au NPs. Moreover, GO/Au nanocomposites exhibit good biocompatibility and accessible surface for high adsorption of target molecules through the pi-pi stacking with graphene oxide. Hence, the proposed GO/Au nanocomposites were utilized to capture aromatic molecules like CB and served as excellent sensitive SERS-active substrates for sensing of it, which exhibited an excellent linear performance in the range of 5 × 10-8 to 1 × 10-6 mol/L with a limit of detection (LOD) of 3.34 × 10-8 mol/L (S/N = 3). Due to high-density hot spots with easy operation, this proposed GO/Au nanocomposite-based SERS technique holds great potential in the application of food safety analysis and biomedical science.


Asunto(s)
Agonistas Adrenérgicos beta/análisis , Clenbuterol/análisis , Oro/química , Grafito/química , Nanocompuestos/química , Espectrometría Raman/métodos , Límite de Detección
8.
Chemosphere ; 241: 124981, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31606579

RESUMEN

Photocatalytic degradation of toxic pollutants is an efficient technique to completely remove the toxic pollutants from water bodies. In the present investigation, photocatalytic degradation of pollutants was studied over porous g-C3N4/H-ZSM-5 nanocomposite under visible light irradiation. The composite g-C3N4/H-ZSM-5 was synthesized by mixing an aqueous solution of H-ZSM-5 zeolite (increases surface area and provides active sites for degradation) with melamine (precursor of g-C3N4) for 10-12 h followed by calcinations at 550 °C. The photocatalyst was characterized by XRD, BET, HRTEM, FESEM, EDS and elemental mapping analysis. These techniques confirmed that, g-C3N4/H-ZSM-5 composite have layered and porous structure with uniform distribution of g-C3N4 on H-ZSM-5 surface. The BET N2 adsorption-desorption analysis verified that the catalyst has high surface area (∼175 m2/g) having mesopores and micropores. The prepared catalyst was then used for the photodegradation of a model dye, Methylene Blue (MB) and an endocrine disrupting compound, Fipronil (FIP). Effects of various parameters such as pH, catalyst dose and scavengers were also studied. The % photocatalytic degradation of MB and FIP were around ∼92% and ∼84% with a high rate constants of 0.00997 and 0.00875 min-1, respectively. From the scavenger study, OH (hydroxyl radical) and radical was found to be the major reactive species for MB and FIP degradation. From these studies it is revealed that, the catalyst is visible active, easy to prepare and an efficient photocatalyst for toxic pollutant degradation.


Asunto(s)
Disruptores Endocrinos/química , Luz , Nanocompuestos/química , Fotólisis , Zeolitas/química , Adsorción , Catálisis , Disruptores Endocrinos/efectos de la radiación , Azul de Metileno/química , Microscopía Electrónica de Transmisión , Porosidad
9.
Chemosphere ; 241: 125020, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31614314

RESUMEN

A nanocomposite of graphene and titanium dioxide (G/TiO2) was prepared using the sol-gel method for use in an electrochemical adsorption/regeneration process. The effect of annealing temperature on electrochemical characteristics of the nanocomposites was investigated by cyclic voltammetry and constant current electrochemical regeneration, using methylene blue (MB) as the adsorbate. The G/TiO2 could be regenerated more rapidly and with less corrosion than the bare graphene. The G/TiO2 annealed at 400 °C had a higher proportion of anatase phase TiO2 (ca. 7% rutile TiO2) compared to that annealed at 500 °C (ca. 40% rutile TiO2). Cyclic voltammetry indicated that the G/TiO2 annealed at 400 °C had a higher activity for MB oxidation than the nanocomposite annealed at 500 °C. Similarly, the regeneration of MB loaded G/TiO2 annealed at 400 °C was much faster than for the nanocomposite annealed at 500 °C. Complete regeneration of the G/TiO2 annealed at 400 °C was obtained after an electrochemical charge of 21 C per mg of adsorbate. The G/TiO2 annealed at 400 °C was regenerated in half the time required for the bare graphene. TEM studies showed that the bare graphene was rapidly corroded, while corrosion was not observed for the G/TiO2 nanocomposites.


Asunto(s)
Colorantes/química , Técnicas Electroquímicas/métodos , Grafito , Nanocompuestos/química , Reciclaje/métodos , Titanio , Adsorción , Corrosión , Electrodos , Azul de Metileno/química
10.
J Photochem Photobiol B ; 202: 111685, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31810035

RESUMEN

Surface tailored GaAu loaded mesoporous silica nanoparticles are considered as an important nanomaterial for biomedical applications such as diagnosis and cancer treatment. In this study, we used GaAu loaded mesoporous silica nanoparticles (Ga-Au@mSiO2) for the photothermal treatment of two prostate cancer cell lines. We systematically examined the nanocomposite form by various spectroscopic (UV-Vis, TGA and DTA) and electroscopic techniques (TEM and SEM including the elemental mapping analysis). After careful evaluation of the nanocomposite form, we performed cancer cell growth inhibition properties of the prostate cancer cell lines (DU145 and LNCaP). Also, we performed the photothermal effects of these nanocomposites on cell proliferation and apoptosis using different biochemical staining and flow cytometry. Our in vitro investigational datas are established Ga-Au@mSiO2 effectively exhibited and also with Ga-Au@mSiO2 + NIR the photothermal conversion therapy improved prostate cancer cells abolishing the prostate cancer cells. Interestingly, Ga-Au@mSiO2 + NIR was found to surpass the activity of Ga-Au@mSiO2 in all the cancer cells tested a topnotches. Hence, our current results demonstrated that surface tailored GaAu loaded mesoporous silica nanoparticles significantly inhibited the growth of prostate cancer cell lines and shown prominent antitumor effect in vitro. Thus, our study suggests that Ga-Au@mSiO2 + NIR could be used as impending anticancer candidate for photothermal ablation of prostate cancer cells. Further examinations of the mechanism indicated that anticancer activity was accomplished by inducing apoptosis in cancer cells, which is suggesting that these Ga-Au@mSiO2 + NIR nanocomposite can be used as promising candidates for nursing care cancer therapy.


Asunto(s)
Galio/química , Oro/química , Rayos Infrarrojos , Nanocompuestos/química , Neoplasias de la Próstata/terapia , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Puntos de Control del Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de la radiación , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Daño del ADN/efectos de la radiación , Humanos , Masculino , Nanocompuestos/uso terapéutico , Nanocompuestos/toxicidad , Atención de Enfermería , Fototerapia , Porosidad , Neoplasias de la Próstata/patología , Dióxido de Silicio/química
11.
J Photochem Photobiol B ; 202: 111666, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31837585

RESUMEN

In this study, the effect of Polyp-Au-GO nanocomposite on VSMC proliferation, cell cycle proteins, down-regulation of mRNA in the rat was tested. Briefly, Polyp-Au-GO composite material was synthesized and characterized by UV-Vis spectra, X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). Polyp-Au-GO composite exhibited the absorbance peak at 530 nm. XRD analysis confirmed the crystalline particle with size ranging between 16.5 and 32.6 nm. The crystallinity differences of the nanocomposite were examined by Raman spectroscopy analysis. The presence of a strong band (1500 cm-1) and the absence of other lower frequency bands confirmed that the absence of crystallinity of Polyp-Au-GO nanocomposite. The thermal properties of Polyp-Au-GO nanocomposite were determined by TGA analysis. The results revealed that 15% of its weight loss has occurred at 300 °C. Further, the growth of VSMCs was inhibited by the treatment of Polyp-Au-GO composite at 72 h. The IC50 value was registered at 0.57 µg/mL. Additionally, the Polyp-Au-GO composite arrest G1 cell cycle and down-regulated cell cycle proteins. These Polyp-Au-GO composite also reduced the extracellular ERK1/2 phosphorylation. Furthermore, Polyp-Au-GO composite inhibited TNF-R-evoked inflammatory responses. Moreover, Polyp-Au-GO composite inhibited of CEC proliferation. These results suggest that Polyp-Au-GO composite inhibits VSMC proliferation and TNF-R-mediated inflammatory responses. This study suggested the therapeutic role of Polyp-Au-GO composite in cardiovascular disease.


Asunto(s)
Grafito/química , Nanocompuestos/química , Polifenoles/química , Animales , Aorta/efectos de los fármacos , Aorta/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , Nanocompuestos/toxicidad , Tamaño de la Partícula , Fosforilación/efectos de los fármacos , Polifenoles/farmacología , Ratas
12.
Chem Biodivers ; 17(1): e1900436, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31705573

RESUMEN

A facile method was developed for synthesis of boronic acid-functionalized silica nanocomposites (SiO2 -BA) by 'thiol-ene' click reaction, where silica nanoparticles were synthesized by using tetraethoxysilane (TEOS) and γ-mercaptopropyl trimethoxysilane (γ-MPTS) as precursors. The morphology and structure properties of the resultant SiO2 -BA were characterized by transmission electronic microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and Brunner-Emmet-Teller measurements (BET). The adsorption behavior of the SiO2 -BA for glycoproteins was evaluated. Under the optimized conditions, the SiO2 -BA exhibited higher adsorption capacity towards glycoproteins (ovalbumin, OVA, 7.64 µmol/g) than non-glycoproteins (bovine serum albumin, BSA, 0.83 µmol/g). In addition, the practicality of the SiO2 -BA was further assessed by selective enrichment of glycoproteins from egg white samples.


Asunto(s)
Ácidos Borónicos/química , Glicoproteínas/química , Nanocompuestos/química , Dióxido de Silicio/química , Adsorción , Clara de Huevo/química , Estructura Molecular , Tamaño de la Partícula , Dióxido de Silicio/síntesis química , Propiedades de Superficie
13.
Chemosphere ; 239: 124728, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31499314

RESUMEN

Numerous of pollutants threaten our planet, for instance plastic wastes causes a huge potential risk on the environment in addition to many of emergened pollutants as pharmaceutical residue in aquatic environments which affecting ecological balance and in-turn affecting human health. Accordingly, this research proposed an innovative facile, one-step synthesis of functionalized magnetic fullerene nanocomposite (FMFN) via catalytic thermal decomposition of sustainable poly (ethylene terephthalate) bottle wastes as feedstock and ferrocene as a catalyst and precursor of magnetite. Growth mechanism of FMFN was discussed and batch experiments were achieved to examine its adsorption efficiency in relation to Ciprofloxacin antibiotic. Different adsorption parameters including time, initial Ciprofloxacin concentration, and solution temperature were investigated and optimized using Response Surface Methodology (RSM) model. In addition, a study on the antibiotic adsorption process impact on the organisms of an ecosystem was conducted using E. coli DH5α, and results validated method's efficiency in overcoming problem of appearance of antibiotic-resistant microbes.


Asunto(s)
Ciprofloxacino/aislamiento & purificación , Fulerenos/química , Nanocompuestos/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Ciprofloxacino/química , Ecosistema , Escherichia coli , Concentración de Iones de Hidrógeno , Cinética , Fenómenos Magnéticos , Modelos Estadísticos , Plásticos , Tereftalatos Polietilenos/química , Tomografía de Emisión de Positrones , Reciclaje , Temperatura Ambiental , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Purificación del Agua/estadística & datos numéricos
14.
Chemosphere ; 239: 124708, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31505442

RESUMEN

The discharge of phenol, a harmful pollutant, in the environment poses a threat to human health. With the rapid urbanization and industrialization of the land, there is a pressing need to find new technologies and efficient adsorption materials to address phenol contamination. As a potential adsorbent candidate, sepiolite (SEP) has garnered much interest owing to its large specific surface area, and excellent adsorption performance and biocompatibility. Herein, nanocomposite CESEP/ZIF-8, consisting of zeolite imidazole framework (ZIF-8) and hydrochloric acid-modified SEP (CESEP), was prepared and examined toward the adsorption of phenol. Adsorption equilibrium was achieved within 150 min at initial phenol solution concentrations of 10 and 20 mg/L. However, complete removal was not achieved. Accordingly, biodegradation was introduced. Microorganism Pseudomonas putida was immobilized onto CESEP/ZIF-8, which afforded synergistic adsorption and biodegradation action. Phenol at solution concentrations of 10 and 20 mg/L was effectively removed within 13 and 24 h, respectively (as opposed to 21 and 36 h when phenol was removed in the presence of free Pseudomonas putida solely). The synergistic physical-biological treatment presented herein is expected to have great potential in the field of wastewater treatment.


Asunto(s)
Biodegradación Ambiental , Imidazoles/química , Nanocompuestos/química , Fenol/aislamiento & purificación , Pseudomonas putida/metabolismo , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Zeolitas , Adsorción , Cinética , Fenol/metabolismo , Fenoles/aislamiento & purificación , Fenoles/metabolismo , Aguas Residuales/química , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/normas
15.
Carbohydr Polym ; 227: 115349, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31590840

RESUMEN

Release of Zn2+ ions from zinc oxide nanoparticles (ZnO NPs) is a major mechanism for oligodynamic activities of these metal oxide NPs against eukaryotic and prokaryotic microorganisms. In addition to this mechanism, ZnO NPs can form reactive oxygen species (ROSs) resulted from electron-hole formation under certain light wavelength. These properties with suitable biocompatibility and biodegradability of ZnO NPs compared to other metal NPs have caused higher applications of these nanomaterials in therapeutic and cosmetic fields. Recently, natural polymers including cellulose, chitosan, and alginate polymers have gained more attention as safe and cost-effective scaffold for wound healing. Both ZnO NPs and these polymers have not been able to satisfy related patients. In this way, the coupling of these materials and nanomaterials as nanocomposites (NCs) is an alternative way to increase the mechanical and antibacterial properties of wound-healing tissue scaffolds. Controllable release of Zn2+ ions in physiological medium should be considered as an indispensable factor to obtain appropriate industrial formulation. Therefore, in this review, attempts were made to highlight particularly important antibacterial results of these NCs in recent investigations.


Asunto(s)
Alginatos , Antibacterianos , Celulosa , Quitosano , Hidrogeles , Nanocompuestos , Nanopartículas , Óxido de Zinc , Alginatos/administración & dosificación , Alginatos/química , Animales , Antibacterianos/administración & dosificación , Antibacterianos/química , Celulosa/administración & dosificación , Celulosa/química , Quitosano/administración & dosificación , Quitosano/química , Humanos , Hidrogeles/administración & dosificación , Hidrogeles/química , Nanocompuestos/administración & dosificación , Nanocompuestos/química , Nanopartículas/administración & dosificación , Nanopartículas/química , Cicatrización de Heridas , Óxido de Zinc/administración & dosificación , Óxido de Zinc/química
16.
Carbohydr Polym ; 227: 115360, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31590866

RESUMEN

Some applications, in particular, wound dressings, require significant water holding capability: hydrogels formed from Basil seed mucilage (BSM) are non-toxic natural substances and exhibit the needed water holding capacity. However, the sponges have low dimensional stability and easily degrade in aqueous media. We overcame this drawback by crosslinking with borax. To provide antibacterial activity, zinc oxide nanoparticles (ZnO-NP) were added. With 10-20 wt% added borax and ZnO-NP, all key properties improved: dimensional stability, water retention capacity (31 to 41%), stress at maximum load (2.6 to 6.6 MPa), Young's modulus (74 to 113 MPa) and strain (28 to 54%). An interconnecting system of pores with well distributed ZnO-NP was observed from scanning electron microscope. In addition, higher borax and ZnO-NP loadings slightly decreased porosity (92% to 73%) and swelling (109 to 56). Moreover, antibacterial activity and cytotoxicity of BSM hydrogel sponge were also examined.


Asunto(s)
Antibacterianos/química , Vendajes , Boratos/química , Sistemas de Liberación de Medicamentos , Nanocompuestos/química , Mucílago de Planta/química , Óxido de Zinc/química , Línea Celular , Supervivencia Celular , Escherichia coli/crecimiento & desarrollo , Humanos , Ocimum basilicum , Semillas , Staphylococcus aureus/crecimiento & desarrollo
17.
Carbohydr Polym ; 227: 115371, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31590869

RESUMEN

In the present work alginate-based nanofibrous membranes embedding zinc oxide nanoparticles (ZnO-NPs) were prepared via electrospinning technique. ZnO-NPs were synthesized by means of a "green" sol-gel method by using alginate itself as stabilizing agent and characterized through UV-vis spectroscopy, thermogravimetric and morphological analysis. Formulations containing sodium alginate, poly(ethylene oxide) and ZnO-NPs were rheologically studied to identify the most suitable ones to be electrospun; alginate molecular structure played an important role on the solution spinnability due to the polysaccharide capability to establish electrostatic interactions and hydrogen bonds with ZnO-NPs. An innovative washing-crosslinking protocol was developed to obtain stable products which composition was assessed using Fourier Transform InfraRed spectroscopy and thermogravimetric analysis. Morphological investigation combined with EDX spectroscopy proved the obtained mats were highly porous and composed by thin homogenous nanofibers with a good distribution of the used nanofillers, thus representing potential products for several purposes (e.g. biomedical, pharmaceutical and environmental applications).


Asunto(s)
Alginatos/química , Membranas Artificiales , Nanocompuestos/química , Nanopartículas/química , Óxido de Zinc/química , Reología , Electricidad Estática
18.
Carbohydr Polym ; 227: 115341, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31590874

RESUMEN

Starch nanocrystal (SNC), was used as the third component to prepare nanocomposites with biodegradable poly(ß-hydroxybutyrate)/poly(butylene succinate) (PHB/PBS) blend. The results reveal that SNC shows strong nucleation to the two matrix polymers. However, the crystallization temperature of PHB is highly dependent on the SNC loadings, whereas that of PBS not. This is because SNCs have preferential localization in the immiscible matrix polymers: mainly dispersed in the continuous PHB phase and on PHB/PBS phase interfaces. Therefore, alteration trend of crystallization temperatures can be used as good probe to evaluate selective localization of SNCs in the immiscible blends containing two semicrystalline polymers. The nucleation activities of SNCs, and their interaction energy densities in the two polyesters, as well as the tensile behaviors of ternary nanocomposites, were then detected, aiming at establishing a simple route to prepare green nanocomposites with tailorable multi-phase morphology and balanced mechanical properties using starch and biodegradable aliphatic polyester blends.


Asunto(s)
Butileno Glicoles/química , Hidroxibutiratos/química , Nanocompuestos/química , Nanopartículas/química , Poliésteres/química , Polímeros/química , Almidón/química , Cristalización , Temperatura Ambiental
19.
Talanta ; 206: 120212, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31514841

RESUMEN

Graphene oxide-Fe3O4 (GO-Fe3O4) nanocomposite was synthesized by a facile chemical co-precipitation method. The GO-Fe3O4 was used as magnetic sorbent to extract the eight psychoactive drugs from urine samples. The analytes are morphine (MOR), 6-monoacetylmorphine (6-MAM), amphetamine (AMP), methamphetamine (MAMP), codeine, cocaine, dolantin and benzoylecgonine (BZE), which were determined by ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). This method has high selectivity for the target analytes. The limit of detection (LOD) and limit of quantification (LOQ) were 0.02-0.2 µg L-1 and 0.05-0.5 µg L-1, respectively. The Mandel's fitting test revealed good linearity within all linear ranges. The linear ranges were calculated as 0.05-1000 µg L-1 for AMP, MAMP, cocaine and dolantin; 0.1-1000 µg L-1 for 6-MAM and codein; and 0.5-1000 µg L-1 for MOR and BZE. The recoveries ranged in 80.4-105.5%. The intra-day and inter-day RSDs are in the range of 2.7-13.1% and 3.9-13.7%, respectively. Magnetic solid phase extraction (MSPE) with GO-Fe3O4 provides a convenient, rapid and green sample pretreatment method for extracting the target psychoactive drugs from urine. This methodology can be used for simultaneous or individual detection of eight major psychoactive drugs with high sensitivity. This method has high potential in clinical and forensic areas for psychoactive drugs analysis.


Asunto(s)
Grafito/química , Nanopartículas de Magnetita/química , Nanocompuestos/química , Psicotrópicos/orina , Cromatografía Líquida de Alta Presión/métodos , Óxido Ferrosoférrico/síntesis química , Grafito/síntesis química , Límite de Detección , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos
20.
Talanta ; 206: 120205, 2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31514877

RESUMEN

We report an attomolar sensitive electrochemical genosensor for the detection of cauliflower mosaic virus 35S (CaMV35S) gene. The sandwich-type genosensor uses gold-silver core-shell (Au@Ag)-loaded iron oxide (Fe3O4) nanocomposite (Fe3O4-Au@Ag) as label of signal DNA probe (sDNA). Electrochemical sensing is accomplished at interface of electrodeposited AuNPs and carboxylated multiwalled carbon nanotubes-modified glassy carbon electrode through the specific interaction between the capture probe and target CaMV35S (tDNA), and tDNA and the labeled sDNA. The detection sensitivity was improved by the amplified reduction signal of hydrogen peroxide (H2O2), which takes advantage of the enhanced electrocatalytic activity of Fe3O4-Au@Ag. Under the optimal experimental conditions, an ultralow limit of detection was calculated to be 1.26 × 10-17 M (S/N = 3), and the blank value subtracted reduction signal of H2O2 of the sensor increased linearly with the logarithm of CaMV35S concentration over a wide range (1 × 10-16 M to 1 × 10-10 M). This genosensor displayed excellent stability, selectivity and reproducibility, and was successful in detecting the target CaMV35S in genetically modified tomato samples.


Asunto(s)
Técnicas Biosensibles/métodos , Caulimovirus/genética , ADN Viral/análisis , Nanopartículas de Magnetita/química , Nanocompuestos/química , Plantas Modificadas Genéticamente/genética , Sondas de ADN/química , Sondas de ADN/genética , ADN Viral/genética , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Electrodos , Oro/química , Peróxido de Hidrógeno/química , Lycopersicon esculentum/genética , Nanotubos de Carbono/química , Hibridación de Ácido Nucleico , Oxidación-Reducción , Plata/química
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