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1.
J Sep Sci ; 47(17): e2400507, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39233475

RESUMEN

Given the limited specificity and accuracy observed in the current official colorimetric quantification of polysaccharide in Lycium barbarum, our study aims to establish a novel, specific, accurate, and economic pre-column derivatization ultra-high-performance liquid chromatography (UHPLC) method for determining the monosaccharide and polysaccharide content in L. barbarum. The optimization of extraction, hydrolysis, and derivatization (using 1-phenyl-3-methyl-5-pyrazolone) processes for polysaccharide from L. barbarum was conducted initially, followed by separation of nine monosaccharides within 20 min using UHPLC with a C18 column. Subsequently, a novel method known as quantitative analysis of multiple components by single marker was developed, utilizing either additive 2-deoxy-D-ribose or any monosaccharide present in the sample as a single reference standard to simultaneously detect the contents of polysaccharide and nine monosaccharides in L. barbarum. To validate the accuracy of the established method, the quantitative results of our approach were compared to both external and internal standard method methods. The minimal relative errors in the quantitative determination of monosaccharides among the three methods confirmed the dependability of the method. By analyzing 20 batches of L. barbarum samples, D-galacturonic acid exhibited the highest content and the polysaccharide levels ranged from 3.02 to 13.04 mg/g. All data implied the specificity and accuracy of the method.


Asunto(s)
Lycium , Monosacáridos , Polisacáridos , Cromatografía Líquida de Alta Presión/métodos , Lycium/química , Monosacáridos/análisis , Monosacáridos/química , Polisacáridos/análisis , Polisacáridos/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis
2.
J Environ Manage ; 341: 118054, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37148766

RESUMEN

Polyvinyl alcohol (PVA), a water-soluble synthetic polymer, is one of the most prevalent non-native polyvinyl alcohols found in the environment. Due to its inherent invisibility, its potential for causing severe environmental pollution is often underestimated. To achieve efficient degradation of PVA in wastewater, a Cu2O@TiO2 composite was synthesized through the modification of titanium dioxide with cuprous oxide, and its photocatalytic degradation of PVA was investigated. The Cu2O@TiO2 composite, supported by titanium dioxide, facilitated photocarrier separation and demonstrated high photocatalytic efficiency. Under alkaline conditions, the composite exhibited a 98% degradation efficiency for PVA solutions and a 58.7% PVA mineralization efficiency. Radical capture experiments and electron paramagnetic resonance (EPR) analyses revealed that superoxide radicals primarily drive the degradation process within the reaction system. Throughout the degradation process, PVA macromolecules are broken down into smaller molecules, including ethanol, and compounds containing aldehyde, ketone, and carboxylic acid functional groups. Although the intermediate products exhibit reduced toxicity compared to PVA, they still pose certain toxic hazards. Consequently, further research is necessary to minimize the environmental impact of these degradation products.


Asunto(s)
Procesos Fotoquímicos , Alcohol Polivinílico , Contaminantes Químicos del Agua , Catálisis , Luz , Titanio , Agua , Contaminantes Químicos del Agua/química
3.
J Environ Sci (China) ; 122: 50-61, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35717090

RESUMEN

The widespread contamination of water systems with antibiotics and heavy metals has gained much attention. Intimately coupled visible -light-responsive photocatalysis and biodegradation (ICPB) provides a novel approach for removing such mixed pollutants. In ICPB, the photocatalysis products are biodegraded by a protected biofilm, leading to the mineralization of refractory organics. In the present study, the ICPB approach exhibited excellent photocatalytic activity and biodegradation, providing up to ∼1.27 times the degradation rate of sulfamethoxazole (SMX) and 1.16 times the Cr(VI) reduction rate of visible-light-induced photocatalysis . Three-dimensional fluorescence analysis demonstrated the synergistic ICPB effects of photocatalysis and biodegradation for removing SMX and reducing Cr(VI). In addition, the toxicity of the SMX intermediates and Cr(VI) in the ICPB process significantly decreased. The use of MoS2/CoS2 photocatalyst accelerated the separation of electrons and holes, with•O2- and h+ attacking SMX and e- reducing Cr(VI), providing an effective means for enhancing the removal and mineralization of these mixed pollutants via the ICPB technique. The microbial community results demonstrate that bacteria that are conducive to pollutant removal are were enriched by the acclimation and ICPB operation processes, thus significantly improving the performance of the ICPB system.


Asunto(s)
Contaminantes Ambientales , Sulfametoxazol , Biopelículas , Catálisis , Cromo , Titanio
4.
Environ Res ; 195: 110840, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33587946

RESUMEN

Intimate coupling of visible-light photocatalysis and biodegradation (ICPB) offers potential for degrading chlorine dioxide bleaching wastewater. In this study, we reported a TiO2-coated sponge biofilm carrier with significant adhesion of TiO2 and the ability to accumulate biomass in its interior. Four mechanisms possibly acting in ICPB were tested separately: adsorption of chlorine dioxide bleaching wastewater to the carrier, photolysis, photocatalysis, and biodegradation by the biofilm inside the carrier. The carrier had an adsorption capacity of 17% and 16% for CODcr and AOX, respectively, in the wastewater. The photodegradation rate of wastewater was very low and could be ignored. Both biodegradation (AOX 30.1%, CODcr 33.8%, DOC 26.2%) and photocatalysis (AOX 65.1%, CODcr 71.2%, DOC 62.3%) possessed a certain degradation efficiency of wastewater. However, the removal rate of AOX, CODcr, and DOC in wastewater treatment by protocol ICPB reached 80.3%, 90.5%, and 86.7%. FT-IR and GC-MS analysis showed that the ICPB system had photocatalytic activity on the surface of the porous carrier in vitro, which could transform organic into small molecules for microbial utilization or complete mineralization. Moreover, the biofilm in the interior of the TiO2-coated sponge carrier could mineralize the photocatalytic products, which enhanced the removal of AOX, CODcr, and DOC by more than 15.2%, 20.0%, and 24.0%, respectively. The biofilm in the carrier of the ICPB system evolved, enriched in Proteobacteria, Chloroflexi, Bacteroidetes, and Actinobacteria, microorganisms known to play active roles in the biodegradation of papermaking wastewater.


Asunto(s)
Titanio , Aguas Residuales , Biodegradación Ambiental , Catálisis , Compuestos de Cloro , Óxidos , Fotólisis , Espectroscopía Infrarroja por Transformada de Fourier
5.
Analyst ; 145(1): 268-276, 2019 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-31746832

RESUMEN

Immobilized enzymes play significant roles in many practical applications. However, the enzymes need to be purified before immobilization by conventional immobilizing methods, and the purification process is expensive, laborious, complicated and results in a decrease of the enzymatic activity. So, we present a novel method by a facile one-step targeted immobilization of an enzyme without a purification process from complex samples. For this purpose, a novel molecularly imprinted polymer was prepared via a silane emulsion self-assembly method using boric acid-modified Fe3O4 nanoparticles as magnetic nuclei, horseradish peroxidase as a template, 3-aminopropyltriethoxysilane as a functional monomer and tetraethyl orthosilicate as a crosslinking agent. The molecularly imprinted polymers were characterized using a scanning electron microscope, X-ray photoelectron spectroscope, vibrating sample magnetometer and X-ray diffractometer. The as-prepared and characterized materials were employed to immobilize horseradish peroxidase from a crude extract of horseradish. Moreover, the immobilized horseradish peroxidase was employed to develop visual sensors for the detection of glucose and sarcosine. This study demonstrated that the molecularly imprinted polymers prepared via the silane emulsion self-assembly method can facilely immobilize horseradish peroxidase from a crude extract of horseradish without any purification process. The developed visual method based on the immobilized horseradish peroxidase shows great potential applications for the visual detection of glucose and sarcosine.


Asunto(s)
Glucemia/análisis , Colorimetría/métodos , Enzimas Inmovilizadas/química , Peroxidasa de Rábano Silvestre/química , Polímeros/química , Sarcosina/orina , Armoracia/enzimología , Bencidinas/química , Glucemia/química , Colorantes/química , Emulsiones/química , Glucosa Oxidasa/química , Humanos , Peróxido de Hidrógeno/química , Nanopartículas de Magnetita/química , Impresión Molecular , Propilaminas/química , Sarcosina/química , Sarcosina-Oxidasa/química , Silanos/química
6.
J Sep Sci ; 42(21): 3352-3362, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31453662

RESUMEN

Pyrrolizidine alkaloids are the most widely distributed natural toxins, and pyrrolizidine alkaloid-containing herbal medicines are probably the most common poisonous plants affecting humans. We reported pyrrolizidine alkaloid-molecularly imprinted polymer solid-phase microextraction for the selective adsorption of toxic pyrrolizidine alkaloids from herbal medicine. A sulfonic compound, sodium allylsulfonate, was chosen as the functional monomer to interact with pyrrolizidine alkaloids through strong ionic interaction. To avoid template leakage and for the aim of cost saving, a relatively cheap dummy template was used for the fabrication of molecularly imprinted polymer-solid-phase microextraction fibers. The obtained fibers showed selective adsorption ability for four pyrrolizidine alkaloids, including europine, echimidine, lasiocarpine, and heliotrine. The extraction parameters, such as extraction time, extraction temperature, shaking speed, elution solvent and elution time, were optimized. Then ultra high performance liquid chromatography with mass spectrometry coupled with molecularly imprinted polymer-solid-phase microextraction method was developed for the fast and efficient analysis of four pyrrolizidine alkaloids from the model herbal plant Farfarae Flos. The established method was validated and exhibited satisfactory accuracy and precision. The present method provides an innovative and fast analytical strategy for the determination of trace toxic pyrrolizidine alkaloids in complicated samples.


Asunto(s)
Impresión Molecular , Polímeros/química , Alcaloides de Pirrolicidina/análisis , Microextracción en Fase Sólida , Tussilago/química , Adsorción , Cromatografía Líquida de Alta Presión , Medicina de Hierbas , Estructura Molecular , Tamaño de la Partícula , Polímeros/síntesis química , Propiedades de Superficie , Espectrometría de Masas en Tándem
7.
Mikrochim Acta ; 186(7): 446, 2019 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-31197478

RESUMEN

A method is described for colorimetric determination of glucose by using hemin-porous graphitic carbon nitride (g-C3N4) hybrid nanosheets as a peroxidase mimic. The porous g-C3N4 nanosheets were prepared by a combination of one-pot self-polymerization, pyrolysis and liquid-phase exfoliation. The hemin-porous g-C3N4 hybrid nanosheets were prepared via in-situ deposition. It is shown that the hybrid composite has improved dispersibility, stability, and peroxidase-mimicking activity in the 3,3',5,5'-tetramethylbenzidine (TMB)/H2O2 system. This is deemed to be the result of the synergistic effect of hemin and porous g-C3N4 nanosheets. Based on these advantages of the nanosheets, a simple, low-cost, sensitive and selective colorimetric method was established for the determination of glucose at pH values around 7. Best performed at a wavelength of 652 nm, the assay has a linear response in the 10.0 µM to 500 µM glucose concentration range (R2 = 0.9942) and a 1.94 µM limit of detection. This method was successfully applied to the determination of glucose in (spiked) human serum samples. In our perception, the hybrid is a robust peroxidase mimic for use in POx-based assays as needed in medical diagnosis and environmental analysis. Graphical abstract Schematic presentation of the process of hemin-porous g-C3N4 hybrid nanosheets catalyzing the oxidation of peroxidase chromogenic substrate tetramethylbenzidine (TMB) in the presence of H2O2. The material was applied in colorimetric and visual determination of H2O2 and glucose.


Asunto(s)
Glucemia/análisis , Colorimetría/métodos , Grafito/química , Hemina/química , Nanoestructuras/química , Compuestos de Nitrógeno/química , Bencidinas/química , Materiales Biomiméticos/síntesis química , Materiales Biomiméticos/química , Colorantes/química , Glucosa Oxidasa/química , Grafito/síntesis química , Humanos , Peróxido de Hidrógeno/química , Límite de Detección , Compuestos de Nitrógeno/síntesis química , Oxidación-Reducción , Peroxidasa/química
8.
J Pharmacol Exp Ther ; 366(2): 332-340, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29891588

RESUMEN

Downregulation of P-glycoprotein (P-gp) is implicated in the pathophysiology of inflammatory bowel disease (IBD). Berberine, a principal isoquinoline alkaloid extracted from Berberis species, has been reported to exhibit therapeutic potential in IBD. In this study, we used a dextran sulfate sodium (DSS)-induced colitis rat model to evaluate the effect of berberine on P-gp and explore its mechanism of action. Berberine treatment improved DSS-induced colitis symptoms, attenuated inflammatory markers (myeloperoxidase, tumor necrosis factor-α, and interleukin-1ß and -6), and enhanced P-gp expression in a dose-dependent manner. Although colonic expression of the P-gp-related nuclear receptor pregnane X receptor and transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) were downregulated in the colitis model, gene and protein expression analysis revealed that berberine treatment reversed only the downregulation of Nrf2. In vitro studies using Caco-2 cells showed that the multidrug resistance 1 (MDR1) gene and P-gp protein were upregulated by berberine in a dose- and time-dependent manner. Significant upregulation of the MDR1 gene by berberine was abrogated by Nrf2 silencing, indicating that the Nrf2-mediated pathway was responsible for this activation. Luciferase assays showed a dose-dependent increase in Nrf2 reporter gene activity after berberine treatment in Caco-2 cells, with a significant 2-fold elevation at 2.5 µM berberine, suggesting that berberine is a strong Nrf2 activator. These results indicate the possible involvement of Nrf2-mediated upregulation of P-gp in the therapeutic effect of berberine on colitis and highlight the potential of P-gp and/or Nrf2 as new therapeutic targets for IBD.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Berberina/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Animales , Células CACO-2 , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Modelos Animales de Enfermedad , Humanos , Masculino , Ratas , Ratas Sprague-Dawley
9.
J Sep Sci ; 41(11): 2441-2452, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29542253

RESUMEN

Dexamethasone-imprinted polymers were fabricated by reversible addition-fragmentation chain transfer polymerization on the surface of magnetic nanoparticles under mild polymerization conditions, which exhibited a narrow polydispersity and high selectivity for dexamethasone extraction. The dexamethasone-imprinted polymers were characterized by scanning electron microscopy, transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive spectrometry, and vibrating sample magnetometry. The adsorption performance was evaluated by static adsorption, kinetic adsorption and selectivity tests. The results confirmed the successful construction of an imprinted polymer layer on the surface of the magnetic nanoparticles, which benefits the characteristics of high adsorption capacity, fast mass transfer, specific molecular recognition, and simple magnetic separation. Combined with high-performance liquid chromatography, molecularly imprinted polymers as magnetic extraction sorbents were used for the rapid and selective extraction and determination of dexamethasone in skincare cosmetic samples, with the accuracies of the spiked samples ranging from 93.8 to 97.6%. The relative standard deviations were less than 2.7%. The limit of detection and limit of quantification were 0.05 and 0.20 µg/mL, respectively. The developed method was simple, fast and highly selective and could be a promising method for dexamethasone monitoring in cosmetic products.


Asunto(s)
Cosméticos/análisis , Dexametasona/aislamiento & purificación , Polímeros/química , Extracción en Fase Sólida/métodos , Adsorción , Cromatografía Líquida de Alta Presión , Dexametasona/análisis , Impresión Molecular , Nanopartículas/química , Polímeros/síntesis química , Extracción en Fase Sólida/instrumentación
10.
J Sep Sci ; 40(13): 2791-2799, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28520091

RESUMEN

In this study, surface molecularly imprinted polymers were prepared as the selective sorbents for separation of aristolochic acid I in herbal medicine extracts by a facile approach. A less toxic dummy template, ofloxacin, was used to create specific molecule recognition sites for aristolochic acid I in the synthesized polymers. The polymers were characterized by Fourier-transfer infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, elemental analysis, and nitrogen adsorption-desorption test. The adsorption capacity was calculated using adsorption kinetics, selectivity, and recycling experiments. The obtained polymers exhibited high thermostability, fast equilibrium time, and excellent binding ability. Subsequently, the polymers applied as the solid-phase extraction absorbent was proposed and used for the enrichment and analysis of aristolochic acid I in herbal plants. The result showed that the aristolochic acid I was enriched up to 16 times after analysis by using high-performance liquid chromatography. The good linearity for aristolochic acid I was obtained in the range of 0.1-200 µg/mL (R2  = 0.9987). The recovery and precision values were obtained (64.94-77.73%, RSDs% ≤ 0.8%, n = 3) at three spiked concentration levels. This work provided a promising method for selective enrichment, extraction, and purification of aristolochic acid I from complex herbal plants.


Asunto(s)
Ácidos Aristolóquicos/análisis , Cromatografía Líquida de Alta Presión , Impresión Molecular , Preparaciones de Plantas/química , Extracción en Fase Sólida , Adsorción , Polímeros
11.
Pak J Pharm Sci ; 28(2 Suppl): 675-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25796144

RESUMEN

In order to the macroscopic geometry distributions of vascular bundles in Moso bamboo tubes. The circumference of bamboo tubes was measured, used a simple quadratic diameter formula to analyze the differences between the tubes in bamboo culm, and the arrangement of vascular bundles was investigated by cross sectional images of bamboo tubes. The results shown that the vascular bundles were differently distributed in a bamboo tube. In the outer layer, the vascular bundles had a variety of shapes, and were aligned parallel to each other. In the inner layers, the vascular bundles weren't aligned but uniform in shape. It was concluded that the vascular bundle sections arranged in parallel should be separated from the non-parallel sections for the maximum bamboo utilization.


Asunto(s)
Haz Vascular de Plantas/citología , Sasa/citología , Modelos Biológicos , Haz Vascular de Plantas/crecimiento & desarrollo , Sasa/crecimiento & desarrollo
12.
IEEE Trans Vis Comput Graph ; 30(1): 716-726, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37874728

RESUMEN

Hairpin vortices are one of the most important vortical structures in turbulent flows. Extracting and characterizing hairpin vortices provides useful insight into many behaviors in turbulent flows. However, hairpin vortices have complex configurations and might be entangled with other vortices, making their extraction difficult. In this work, we introduce a framework to extract and separate hairpin vortices in shear driven turbulent flows for their study. Our method first extracts general vortical regions with a region-growing strategy based on certain vortex criteria (e.g., λ2) and then separates those vortices with the help of progressive extraction of ( λ2) iso-surfaces in a top-down fashion. This leads to a hierarchical tree representing the spatial proximity and merging relation of vortices. After separating individual vortices, their shape and orientation information is extracted. Candidate hairpin vortices are identified based on their shape and orientation information as well as their physical characteristics. An interactive visualization system is developed to aid the exploration, classification, and analysis of hairpin vortices based on their geometric and physical attributes. We also present additional use cases of the proposed system for the analysis and study of general vortices in other types of flows.

13.
Artículo en Inglés | MEDLINE | ID: mdl-38427539

RESUMEN

Hex-dominant mesh generation has received significant attention in recent research due to its superior robustness compared to pure hex-mesh generation techniques. In this work, we introduce the first structure for analyzing hex-dominant meshes. This structure builds on the base complex of pure hex-meshes but incorporates the non-hex elements for a more comprehensive and complete representation. We provide its definition and describe its construction steps. Based on this structure, we present an extraction and categorization of sheets using advanced graph matching techniques to handle the non-hex elements. This enables us to develop an enhanced visual analysis of the structure for any hex-dominant meshes.We apply this structure-based visual analysis to compare hex-dominant meshes generated by different methods to study their advantages and disadvantages. This complements the standard quality metric based on the non-hex element percentage for hex-dominant meshes. Moreover, we propose a strategy to extract a cleaned (optimized) valence-based singularity graph wireframe to analyze the structure for both mesh and sheets. Our results demonstrate that the proposed hybrid base complex provides a coarse representation for mesh element, and the proposed valence singularity graph wireframe provides a better internal visualization of hex-dominant meshes.

14.
Anal Methods ; 16(34): 5896-5901, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39157953

RESUMEN

The uric acid (UA) level is an important physiological indicator of the human body, and its abnormality can lead to a series of diseases. Therefore, the immediate detection of uric acid concentration has broad application prospects. Commonly used methods for the analysis of uric acid include chromatography, high-performance capillary electrophoresis and electrochemical methods. However, these methods have the disadvantages of cumbersome sample pre-treatment, high cost, time-consuming, and the need for experimental instruments and professional operators, which are extremely unfavorable for the detection of uric acid and the diagnosis of related diseases in resource-limited areas. In this study, a portable visualization method was developed for the detection of uric acid using hydrogen peroxide (H2O2) test strips. Uric acid enzyme specifically catalyzes the oxidation of uric acid to produce H2O2, which causes a significant change in the color of the H2O2 test strip. The response has good linearity in the range of 1 ∼ 50 µg mL-1. Thus, it provides a simple, rapid, and cost-effective visualized bioassay for uric acid.


Asunto(s)
Colorimetría , Peróxido de Hidrógeno , Ácido Úrico , Ácido Úrico/análisis , Colorimetría/métodos , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/análisis , Humanos , Urato Oxidasa/química , Límite de Detección , Tiras Reactivas
15.
ArXiv ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38654761

RESUMEN

Microvascular networks are challenging to model because these structures are currently near the diffraction limit for most advanced three-dimensional imaging modalities, including confocal and light sheet microscopy. This makes semantic segmentation difficult, because individual components of these networks fluctuate within the confines of individual pixels. Level set methods are ideally suited to solve this problem by providing surface and topological constraints on the resulting model, however these active contour techniques are extremely time intensive and impractical for terabyte-scale images. We propose a reformulation and implementation of the region-scalable fitting (RSF) level set model that makes it amenable to three-dimensional evaluation using both single-instruction multiple data (SIMD) and single-program multiple-data (SPMD) parallel processing. This enables evaluation of the level set equation on independent regions of the data set using graphics processing units (GPUs), making large-scale segmentation of high-resolution networks practical and inexpensive. We tested this 3D parallel RSF approach on multiple data sets acquired using state-of-the-art imaging techniques to acquire microvascular data, including micro-CT, light sheet fluorescence microscopy (LSFM) and milling microscopy. To assess the performance and accuracy of the RSF model, we conducted a Monte-Carlo-based validation technique to compare results to other segmentation methods. We also provide a rigorous profiling to show the gains in processing speed leveraging parallel hardware. This study showcases the practical application of the RSF model, emphasizing its utility in the challenging domain of segmenting large-scale high-topology network structures with a particular focus on building microvascular models.

16.
ACS Appl Mater Interfaces ; 16(5): 6261-6273, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38270078

RESUMEN

The on-demand regulation of cell wall microstructures is crucial for developing wood as a functional building material for energy management and conversion. Here, a novel strategy based on reactive deep eutectic solvent is developed to one-step in situ fibrillate wood via disrupting the hydrogen bonding networks in cell walls and simultaneously carboxylating wood components, without significantly altering the native hierarchical structures of wood. Benefiting from its distinctive cell wall structure composed of individualized yet well-organized lignocellulose nanofibrils, in situ fibrillated wood exhibits a prominent mesoporous structure with a specific surface area of 81 m2/g. It represents a robust sponge material (5 MPa at 80% strain) with excellent durability. Due to the enhanced compressibility and charge polarization capacity, the in situ fibrillated wood (10 × 11 × 12 mm3) can generate a piezoelectric output voltage of up to 2 V under 221 kPa stress. The favorable microstructural characteristics render in situ fibrillated wood with highly thermal-insulating properties, high solar reflectivity, and mid-infrared emissivity, favoring outdoor passive cooling effects with a subambient temperature drop of 6 °C. Combining its controllable, durable, and eco-friendly attributes, our developed wood sponge represents a versatile structural material suitable for indoor/outdoor energy-saving applications.

17.
J Chromatogr A ; 1732: 465260, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39142168

RESUMEN

Molecularly imprinted polymers (MIPs) are promising for precise protein separation and purification. However, challenges persist due to their large size, variable configuration, and instability during preparation. Here, a simple silicon self-assembly program was designed to synthesize MIPs without any organic reagents and acid-base catalysis, avoiding the structural damage of protein under severe conditions. In this method, employing hemoglobin (Hb) as a model protein, with tween-20 in emulsification, and tetraethyl orthosilicate (TEOS) as the cross-linking agent, along with co-functional monomers 3-aminopropyltriethoxysilane (APTES) and benzyl(triethoxy)silane (BnTES), enhanced binding efficacy was achieved. Successful imprinting was evidenced through surface morphology observation and physical/chemical property evaluations of the synthesized MIPs. A series of adsorption experiments were performed to investigate the recognition performance of Hb-MIPs. The Hb-MIPs not only exhibited large adsorption capacity (400 µg/mg) and good imprinting factor (6.09) toward template protein, but also showed satisfactory selectivity for reference proteins. Five cycles of adsorption proved that the Hb-MIPs had good reusability. In addition, the successful isolation of HB from bovine blood indicated that Hb-MIPs were an excellent separation and purification material. The mild preparation conditions and good adsorption capacity demonstrated the potential value of this method in separation and purification research.


Asunto(s)
Hemoglobinas , Polímeros Impresos Molecularmente , Nanopartículas , Dióxido de Silicio , Polímeros Impresos Molecularmente/química , Adsorción , Dióxido de Silicio/química , Animales , Hemoglobinas/química , Hemoglobinas/aislamiento & purificación , Bovinos , Nanopartículas/química , Impresión Molecular , Polimerizacion , Silanos/química
18.
Biosens Bioelectron ; 261: 116510, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38905859

RESUMEN

The discovery of enzyme inhibitors from natural products is a crucial aspect in the development of therapeutic drugs. However, the complexity of natural products presents a challenge in developing simple and efficient methods for inhibitor screening. Herein, we have developed an integrated analytical model for screening xanthine oxidase (XOD) inhibitors that combines simplicity, accuracy, and efficiency. This model utilizes a colorimetric sensor and affinity chromatography technology with immobilized XOD. The colorimetric sensor procedure can quickly identify whether there are active components in complex samples. Subsequently, the active components in the samples identified by the colorimetric sensor procedure were further captured, separated, and identified through affinity chromatography. The integrated analytical model can significantly enhance the efficiency and accuracy of inhibitor screening. The proposed method was applied to screen for an activity inhibitor of XOD in five natural medicines. As a result, a potential active ingredient for XOD, polydatin, was successfully identified from Polygoni Cuspidati Rhizoma et Radix. This work is anticipated to offer new insights for the screening of enzyme inhibitors from natural medicines.


Asunto(s)
Técnicas Biosensibles , Cromatografía de Afinidad , Colorimetría , Inhibidores Enzimáticos , Xantina Oxidasa , Xantina Oxidasa/antagonistas & inhibidores , Xantina Oxidasa/química , Cromatografía de Afinidad/métodos , Colorimetría/métodos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/análisis , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Técnicas Biosensibles/métodos , Enzimas Inmovilizadas/química , Evaluación Preclínica de Medicamentos , Humanos
19.
J Chromatogr A ; 1720: 464822, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38502989

RESUMEN

α-Glucosidase plays a direct role in the metabolic pathways of starch and glycogen, any dysfunction in its activity could result in metabolic disease. Concurrently, this enzyme serves as a target for diverse drugs and inhibitors, contributing to the regulation of glucose metabolism in the human body. Here, an integrated analytical method was established to screen inhibitors of α-glucosidase. This step-by-step screening model was accomplished through the biosensing and affinity chromatography techniques. The newly proposed sensing program had a good linear relationship within the enzyme activity range of 0.25 U mL-1 to 1.25 U mL-1, which can quickly identify active ingredients in complex samples. Then the potential active ingredients can be captured, separated, and identified by an affinity chromatography model. The combination of the two parts was achieved by an immobilized enzyme technology and a microdevice for reaction, and the combination not only ensured efficiency and accuracy for inhibitor screening but also eliminated the occurrence of false positive results in the past. The emodin, with a notable inhibitory effect on α-glucosidase, was successfully screened from five traditional Chinese medicines using this method. The molecular docking results also demonstrated that emodin was well embedded into the active pocket of α-glucosidase. In summary, the strategy provided an efficient method for developing new enzyme inhibitors from natural products.


Asunto(s)
Emodina , Inhibidores de Glicósido Hidrolasas , Humanos , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/química , Simulación del Acoplamiento Molecular , alfa-Glucosidasas/metabolismo , Cromatografía de Afinidad , Extractos Vegetales/química
20.
Talanta ; 275: 126083, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38636442

RESUMEN

MicroRNA (miRNA) is a promising biomarker that plays an important role in various biomedical applications, especially in cancer diagnosis. However, the current miRNA detection technology has inherent limitations such as complex operation, expensive testing cost and excessive detection time. In this study, a dual signal amplification biosensor based on DNA-functionalized metal-organic frameworks (MOFs) fluorescent probes, MFPBiosensor, was established for the enzyme-free and pretreatment-free detection of the colon cancer (CC) marker miR-23a. DNA-functionalized MOFs NH2-MIL-53(Al) (DNA@MOFs) were synthesized as fluorescent probes with specific recognition functions. A single DNA@MOF carries a large number of fluorescent ligands 2-aminoterephthalic acid (NH2-H2BDC), which can generate strong fluorescence signals after alkaline hydrolysis. Combined with catalyzed hairpin assembly (CHA), an efficient isothermal amplification technique, the dual signal enhancement strategy reduced matrix interference and sensitized the signal response. The established MFPBiosensor successfully detected extremely low levels of miRNA in complex biological samples with acceptable sensitivity and specificity. With a single detection cost of $0.583 and a test time of 50 min, the excellent inexpensive and rapid advantage of the MFPBiosensor is highlighted. More importantly, the subtle design enables the MFPBiosensor to achieve convenient batch detection, where miRNA in serum can be directly detected without any pretreatment process or enzyme. In conclusion, MFPBiosensor is a promising biosensor with substantial potential for commercial miRNA detection and clinical diagnostic applications of CC.


Asunto(s)
Técnicas Biosensibles , ADN , Colorantes Fluorescentes , Estructuras Metalorgánicas , MicroARNs , Estructuras Metalorgánicas/química , MicroARNs/sangre , MicroARNs/análisis , Colorantes Fluorescentes/química , Humanos , ADN/química , ADN/sangre , Técnicas Biosensibles/métodos , Límite de Detección
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