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1.
J Hazard Mater ; 476: 135086, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39024762

RESUMEN

Membranes for wastewater treatment should ideally exhibit sustainable high permeate production, enhanced pollutant removal, and intrinsic physical rejection. In this study, CoFe2O4/MoS2 serves as a non-homogeneous phase catalyst; it is combined with polyether sulfone membranes via liquid-induced phase separation to simultaneously sustain membrane permeability and enhance antibiotic pollutant degradation. The prepared catalytic membranes have higher pure water flux (329.34 L m-2 h-1) than pristine polyethersulfone membranes (219.03 L m-2 h-1), as well as higher mean pore size, porosity, and hydrophilicity. Under a moderate transmembrane pressure (0.05 MPa), tetracycline (TC) in synthetic and real wastewater was degraded by the optimal catalytic membrane by 72.7 % and 91.2 %, respectively. Owing to the generation of the reactive oxygen species (ROS) during the Fenton-like reaction process, the catalytic membrane could exclude the natural organics during the H2O2 backwash step and selectively promote fouling degradation in the membrane channel. The irreversible fouling ratio of the catalyzed membrane was significantly reduced, and the flux recovery rate increased by up to 91.6 %. A potential catalytic mechanism and TC degradation pathways were proposed. This study offers valuable insights for designing catalytic membranes with enhanced filtration performance.


Asunto(s)
Antibacterianos , Disulfuros , Peróxido de Hidrógeno , Membranas Artificiales , Molibdeno , Permeabilidad , Contaminantes Químicos del Agua , Peróxido de Hidrógeno/química , Catálisis , Contaminantes Químicos del Agua/química , Antibacterianos/química , Disulfuros/química , Molibdeno/química , Sulfonas/química , Tetraciclina/química , Cobalto/química , Aguas Residuales/química , Purificación del Agua/métodos , Eliminación de Residuos Líquidos/métodos , Compuestos Férricos/química , Compuestos Ferrosos/química , Polímeros
2.
Front Public Health ; 12: 1264082, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38504681

RESUMEN

Background: This study aimed to evaluate the causal impact of common modifiable lifestyles on obstructive sleep apnea (OSA), which is beneficial for recommendations to prevent and manage OSA. Method: Published genome-wide association study (GWAS) summary statistics were used to perform two-sample Mendelian randomization (MR). Variants associated with each exposure of smoking, drinking, and leisure sedentary behaviors at the genetic level were used as instrumental variables (IVs). Then, inverse-variance weighting (IVW) was considered the primary result for causality. Moreover, several complimented approaches were also included to verify the observed associations. MR-PRESSO and MR-Egger intercept were applied to test the horizontal pleiotropy. To assess heterogeneity, Cochran's Q test by IVW and MR-Egger were applied. Results: Regular smoking history increased OSA risk in all applied approaches [OR (95% CI)IVW = 1.28 (1.12, 1.45), p = 1.853 × 10-4], while the causality of lifetime smoking index [OR (95% CI)IVW = 1.39 (1.00, 1.91), p = 0.048], alcohol intake frequency [outliers removed OR (95% CI)IVW = 1.26 (1.08, 1.45), p = 0.002], and coffee intake behavior [OR (95% CI)IVW = 1.66 (1.03, 2.68), p = 0.039] on OSA risk were not always consistent in other approaches. In addition, no robust causal associations were observed for the effect of sedentary leisure behaviors on OSA risk. In sensitivity analysis, we observed no sign of horizontal pleiotropy or heterogeneity. Conclusion: Ever regularly smoking has a robust causal role in increasing OSA risk, which should be discouraged as precautions from developing OSA.


Asunto(s)
Apnea Obstructiva del Sueño , Fumar , Humanos , Fumar/efectos adversos , Estudio de Asociación del Genoma Completo , Nonoxinol
3.
J Sep Sci ; 33(13): 2026-34, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20512809

RESUMEN

A technique based on strip dispersion hybrid liquid membrane was developed for the separation and extraction of four main alkaloids from fruits of Macleaya cordata (Willd) R. Br. A microporous polypropylene membrane impregnated with an organic membrane solution comprised the heart of the strip dispersion hybrid liquid membrane system. The membrane solution was made by dissolving a cationic carrier, di-(2-ethylhexyl) phosphoric acid in an inexpensive, less toxic membrane solvent, kerosene. The transport of alkaloids from an aqueous feed solution through the membrane to a strip dispersion phase was driven by the concentration gradient of H(+) and facilitated by di-(2-ethylhexyl) phosphoric acid. The effects of the extraction time and reuse times of the membrane, the strip solution composition, the carrier concentration, the volume ratio of the aqueous strip solution to the organic membrane solution, and the flow rates of the feed solution and the strip dispersion phase on the transport of alkaloids were investigated. Under the optimal conditions, the permeability coefficients obtained for the four main alkaloids allocryptopine, protopine, sanguinarine, and chelerythrine were 1.66, 1.99, 2.98, and 3.06 x 10(-4) cm/s, and the transport efficiencies were as high as 68, 77, 83, and 85%, respectively.


Asunto(s)
Alcaloides/aislamiento & purificación , Frutas/química , Membranas Artificiales , Organofosfatos/química , Papaveraceae/química , Queroseno , Estructura Molecular , Tamaño de la Partícula , Porosidad , Propiedades de Superficie
4.
J Chromatogr A ; 1625: 461338, 2020 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-32709362

RESUMEN

Until today, ion-pair reversed-phase chromatography is still the dominating method for analytical characterization of synthetic oligonucleotides. Its hyphenation with mass spectrometry, however, has some drawbacks such as ion-suppression in electrospray ionization. To overcome this problem, we present in this work a multiple heart-cutting (MHC) two-dimensional liquid chromatography (2D-LC) method with ultra-violet (UV) and electrospray ionization (ESI) mass spectrometry (MS) detection. A reversed-phase/weak anion-exchange (RP/WAX) stationary phase in the first dimension (1D) provides the selectivity for separation of structurally closely related oligonucleotide sequences and deletions (shortmers), respectively, using a mixed pH/triethylammonium phosphate buffer gradient at constant organic modifier content. Heart cuts of the oligonucleotide peaks are transferred to the second dimension (2D) via a multiple heart-cutting valve which is equipped with two loop decks. The 2D RP column is used for desalting via a diverter valve. Active solvent modulation enables to refocus the oligonucleotide peak into a sharp zone by 2D RP entirely free of non-volatile buffer components and ion-pair agents. Oligonucleotides can thus be sensitively detected by ESI-QTOF-MS under MS-compatible conditions.


Asunto(s)
Cromatografía de Fase Inversa/métodos , Oligonucleótidos/química , Oligonucleótidos/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray/métodos , Aniones , Cromatografía por Intercambio Iónico , Oligonucleótidos/análisis , Polímeros/química
5.
Biosens Bioelectron ; 92: 396-401, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-27829555

RESUMEN

Zwitterionic peptides were anchored to a conducting polymer of citrate doped poly(3,4-ethylenedioxythiophene) (PEDOT) via the nickel cation coordination, and the obtained peptide modified PEDOT, with excellent antifouling ability and good conductivity, was further used for the immobilization of a DNA probe to construct an electrochemical biosensor for the breast cancer marker BRCA1. The DNA biosensor was highly sensitive (with detection limit of 0.03fM) and selective, and it was able to detect BRCA1 in 5% (v/v) human plasma with satisfying accuracy and low fouling. The marriage of antifouling and biocompatible peptides with conducting polymers opened a new avenue to construct electrochemical biosensors capable of assaying targets in complex biological media with high sensitivity and without biofouling.


Asunto(s)
Proteína BRCA1/genética , Técnicas Biosensibles/métodos , Compuestos Bicíclicos Heterocíclicos con Puentes/química , ADN/sangre , ADN/genética , Péptidos/química , Polímeros/química , ADN/análisis , Sondas de ADN/química , Sondas de ADN/genética , Técnicas Electroquímicas/métodos , Humanos , Ácidos Nucleicos Inmovilizados/química , Ácidos Nucleicos Inmovilizados/genética , Límite de Detección
6.
Biosens Bioelectron ; 19(6): 563-74, 2004 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-14683640

RESUMEN

A piezoelectric immunosensor was developed for rapid detection of Escherichia coli O157:H7. It was based on the immobilization of affinity-purified antibodies onto a monolayer of 16-mercaptohexadecanoic acid (MHDA), a long-chain carboxylic acid-terminating alkanethiol, self-assembled on an AT-cut quartz crystal's Au electrode surface with N-hydroxysuccinimide (NHS) ester as a reactive intermediate. The binding of target bacteria onto the immobilized antibodies decreased the sensor's resonant frequency, and the frequency shift was correlated to the bacterial concentration. The stepwise assembly of the immunosensor was characterized by means of both quartz crystal microbalance (QCM) and cyclic voltammetry techniques. Three analytical procedures, namely immersion, dip-and-dry and flow-through methods, were investigated. The immunosensor could detect the target bacteria in a range of 10(3)-10(8)CFU/ml within 30-50 min, and the sensor-to-sensor reproducibility obtained at 10(3) and 10(5) colony-forming units (CFU)/ml was 18 and 11% R.S.D., respectively. The proposed sensor was comparable to Protein A-based piezoelectric immunosensor in terms of the amount of immobilized antibodies and detection sensitivity.


Asunto(s)
Anticuerpos/inmunología , Técnicas Biosensibles/instrumentación , Electroquímica/instrumentación , Escherichia coli O157/inmunología , Escherichia coli O157/aislamiento & purificación , Inmunoensayo/instrumentación , Complejo Antígeno-Anticuerpo/análisis , Complejo Antígeno-Anticuerpo/inmunología , Técnicas Biosensibles/métodos , Materiales Biocompatibles Revestidos/síntesis química , Electroquímica/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Inmunoensayo/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
ACS Appl Mater Interfaces ; 6(15): 12808-14, 2014 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-25019407

RESUMEN

We report here three-dimensional graphene networks (3D-GNs) as a novel substrate for the immobilization of laccase (Lac) and dopamine (DA) and its application in glucose/O2 biofuel cell. 3D-GNs were synthesized with an Ni(2+)-exchange/KOH activation combination method using a 732-type sulfonic acid ion-exchange resin as the carbon precursor. The 3D-GNs exhibited an interconnected network structure and a high specific surface area. DA was noncovalently functionalized on the surface of 3D-GNs with 3,4,9,10-perylene tetracarboxylic acid (PTCA) as a bridge and used as a novel immobilized mediating system for Lac-based bioelectrocatalytic reduction of oxygen. The 3D-GNs-PTCA-DA nanocomposite modified glassy carbon electrode (GCE) showed stable and well-defined redox current peaks for the catechol/o-quinone redox couple. Due to the mediated electron transfer by the 3D-GNs-PTCA-DA nanocomposite, the Nafion/Lac/3D-GNs-PTCA-DA/GCE exhibited high catalytic activity for oxygen reduction. The 3D-GNs are proven to be a better substrate for Lac and its mediator immobilization than 2D graphene nanosheets (2D-GNs) due to the interconnected network structure and high specific surface area of 3D-GNs. A glucose/O2 fuel cell using Nafion/Lac/3D-GNs-PTCA-DA/GCE as the cathode and Nafion/glucose oxidase/ferrocence/3D-GNs/GCE as the anode can output a maximum power density of 112 µW cm(-2) and a short-circuit current density of 0.96 mA cm(-2). This work may be helpful for exploiting the popular 3D-GNs as an efficient electrode material for many other biotechnology applications.


Asunto(s)
Fuentes de Energía Bioeléctrica , Dopamina/metabolismo , Enzimas Inmovilizadas/metabolismo , Glucosa/análisis , Grafito/química , Lacasa/metabolismo , Oxígeno/análisis , Técnicas Electroquímicas , Electrodos , Polímeros de Fluorocarbono/química , Microscopía Electrónica de Rastreo , Perileno/análogos & derivados , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Especificidad por Sustrato , Trametes/enzimología , Difracción de Rayos X
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