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1.
Biosens Bioelectron ; 261: 116492, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38870828

RESUMEN

Exosomes have been considered as promising biomarkers for cancer diagnosis due to their abundant information from originating cells. However, sensitive and reliable detection of exosomes is still facing technically challenges due to the lack of a sensing platform with high sensitivity and reproducibility. To address the challenges, here we propose a portable surface plasmon resonance (SPR) sensing of exosomes with a three-layer Au mirror/SiO2 spacer/Au nanohole sensor, fabricated by an economical polystyrene nanosphere self-assembly method. The SiO2 spacer can act as an optical cavity and induce mode hybridization, leading to excellent optimization of both sensitivity and full width at half maximum compared with normal single layer Au nanohole sensors. When modified with CD63 or EpCAM aptamers, a detection of limit (LOD) of as low as 600 particles/µL was achieved. The sensors showed good capability to distinguish between non-tumor derived L02 exosomes and tumor derived HepG2 exosomes. Additionally, high reproducibility was also achieved in detection of artificial serum samples with RSD as low as 2%, making it feasible for clinical applications. This mode hybridization plasmonic sensor provides an effective approach to optimize the detection sensitivity of exosomes, pushing SPR sensing one step further towards cancer diagnosis.


Asunto(s)
Exosomas , Oro , Límite de Detección , Dióxido de Silicio , Resonancia por Plasmón de Superficie , Exosomas/química , Humanos , Oro/química , Dióxido de Silicio/química , Aptámeros de Nucleótidos/química , Molécula de Adhesión Celular Epitelial , Tetraspanina 30 , Células Hep G2 , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Reproducibilidad de los Resultados , Diseño de Equipo , Nanosferas/química , Hibridación de Ácido Nucleico , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/análisis
2.
Phys Chem Chem Phys ; 26(25): 17817-17829, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38884203

RESUMEN

There is currently a great deal of interest in realizing localized surface plasmon resonances (LSPRs) in two distinct windows in the near-infrared (NIR) spectrum for in vivo biosensing and medical applications, the biological window (BW) I and II (BW I, 700-900 nm; BW II, 1000-1700 nm). This study aims to demonstrate that LSPRs of Ga-doped ZnO (GZO) core-silver (Ag) shell structures exhibit promising features for biological applications in the NIR BW I and II. Here, we study three different shapes for nanoshells: the core-shell nanosphere, nanorod, and nanodisk. In the calculation of the optical response of these nanoshells, an effective medium approach is first used to reduce the dielectric function of a nanoshell to that of an equivalent homogenous NP with an effective dielectric function. Then, the LSPR spectra of nanoshells are calculated using the modified long-wavelength approximation (MLWA), which corrects the polarizability of the equivalent NP as obtained by Gans theory. Through numerical investigations, we examine the impacts of the core and shell sizes of the proposed nanoshells as well as the medium refractive index on the position and line width of the plasmon resonance peaks. It is shown that the plasmon resonances of the three proposed nanoshells exhibit astonishing resonance tunability in the NIR region by varying their geometrical parameters. Specifically, the improved spectrum characteristics and tunability of its plasmon resonances make the GZO-Ag nanosphere a more viable platform for NIR applications than the spherical metal colloid. Furthermore, we demonstrate that the sensitivity and figure of merit (FOM) of the plasmon resonances may be significantly increased by using GZO-Ag nanorods and nanodisks in place of GZO-Ag nanospheres. It is found that the optical properties of the transverse plasmon resonance of the GZO-Ag nanodisk are superior to all plasmon resonances produced by the GZO-Ag nanorods and GZO-Ag nanospheres in terms of sensitivity and FOM. The FOM of the transverse plasmon mode of the GZO-Ag nanodisk is almost two orders of magnitude higher than that of the longitudinal and transverse plasmon modes of the GZO-Ag nanorod in BW I and BW II. And it is 1.5 and 2 times higher than the plasmon resonance FOM of GZO-Ag nanospheres in BW I and BW II, respectively.


Asunto(s)
Técnicas Biosensibles , Nanosferas , Nanotubos , Plata , Resonancia por Plasmón de Superficie , Óxido de Zinc , Plata/química , Nanotubos/química , Óxido de Zinc/química , Técnicas Biosensibles/métodos , Nanosferas/química , Galio/química , Rayos Infrarrojos
3.
Nanoscale ; 16(26): 12459-12473, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38855854

RESUMEN

Vanillin (VAN), the primary aroma compound in vanilla, contributes significantly to sensory delight; however, its unrestrained presence poses notable health risks. In response to the demanding concern regarding food safety, researchers have directed their efforts towards the detection of VAN, seeking sustainable strategies for contamination prevention. A groundbreaking solution has emerged in the form of a novel sensing platform, whose core lies on a finely tuned electrode, crafted through the incorporation of nano-sized NdNbO4 spheres onto carbon nanofibers (CNFs). This incorporation serves to augment the capabilities of a glassy carbon electrode (GCE), transforming it into a highly sensitive detector primed for vanillin detection. The NdNbO4/f-CNF nanocomposite embodies a paradigm of synergistic collaboration, wherein the nonlinear cumulative effects of synergism and quantum confinement impart exceptional performance characteristics. Notably, the sensor achieves a low detection limit of 6.3 nmol L-1, indicative of its remarkable sensitivity of 2.3 µA µ(mol L-1)-1 cm-2 and precision of 1.519 and 4.72%. Moreover, the sensor boasts a wide linear range spanning from 0.001 to 63.101 µmol L-1. These attributes, coupled with its discerning selectivity and robust stability, underscore its efficacy as a versatile tool for vanillin detection. Indeed, its successful deployment in monitoring food samples underscores its applicability across diverse culinary contexts, further cementing its status as a pivotal asset in safeguarding food quality and consumer well-being.


Asunto(s)
Benzaldehídos , Carbono , Nanofibras , Benzaldehídos/química , Nanofibras/química , Carbono/química , Técnicas Electroquímicas/métodos , Límite de Detección , Electrodos , Nanosferas/química , Nanocompuestos/química
4.
ACS Appl Mater Interfaces ; 16(26): 33963-33970, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38910448

RESUMEN

A tumor microenvironment (TME)-responsive nanoprobe composed of a fluorescent dye-decorated silicon (Si) nanosphere core and a thin MnO2 shell is proposed for simple and intelligent detection of cancer cells. The Si nanosphere core with diameters of 100-200 nm provides environment-independent Mie scattering imaging, while, simultaneously, the MnO2 shell provides the capability to switch the on/off state of the dye fluorescence reacted to the glutathione (GSH) and/or H2O2 levels in a cancer cell. Si-MnO2 core-shell nanosphere probes are fabricated in a solution-based process from crystalline Si nanosphere cores. The fluorescence switching under exposure to GSH is demonstrated, and the mechanism is discussed based on detailed optical characterizations including single-particle spectroscopy. Different types of human cells are incubated with the nanoprobes, and a proof of concept experiment is performed. From the combination of the robust scattering images and GSH- and H2O2-sensitive fluorescence images, the feasibility of cancer cell detection by the multimodal nanoprobes is demonstrated.


Asunto(s)
Colorantes Fluorescentes , Glutatión , Peróxido de Hidrógeno , Compuestos de Manganeso , Nanosferas , Óxidos , Silicio , Humanos , Compuestos de Manganeso/química , Silicio/química , Óxidos/química , Nanosferas/química , Peróxido de Hidrógeno/análisis , Peróxido de Hidrógeno/química , Glutatión/química , Colorantes Fluorescentes/química , Neoplasias/diagnóstico por imagen , Línea Celular Tumoral , Imagen Óptica , Microambiente Tumoral
5.
Molecules ; 29(11)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38893303

RESUMEN

In this study, we designed a novel electrochemical sensor by modifying a glass carbon electrode (GCE) with Pd confined mesoporous carbon hollow nanospheres (Pd/MCHS) for the simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The structure and morphological characteristics of the Pd/MCHS nanocomposite and the Pd/MCHS/GCE sensor are comprehensively examined using SEM, TEM, XRD and EDX. The electrochemical properties of the prepared sensor are investigated through CV and DPV, which reveal three resolved oxidation peaks for AA, DA, and UA, thereby verifying the simultaneous detection of the three analytes. Benefiting from its tailorable properties, the Pd/MCHS nanocomposite provides a large surface area, rapid electron transfer ability, good catalytic activity, and high conductivity with good electrochemical behavior for the determination of AA, DA, and UA. Under optimized conditions, the Pd/MCHS/GCE sensor exhibited a linear response in the concentration ranges of 300-9000, 2-50, and 20-500 µM for AA, DA, and UA, respectively. The corresponding limit of detection (LOD) values were determined to be 51.03, 0.14, and 4.96 µM, respectively. Moreover, the Pd/MCHS/GCE sensor demonstrated outstanding selectivity, reproducibility, and stability. The recovery percentages of AA, DA, and UA in real samples, including a vitamin C tablet, DA injection, and human urine, range from 99.8-110.9%, 99.04-100.45%, and 98.80-100.49%, respectively. Overall, the proposed sensor can serve as a useful reference for the construction of a high-performance electrochemical sensing platform.


Asunto(s)
Ácido Ascórbico , Carbono , Dopamina , Técnicas Electroquímicas , Límite de Detección , Nanosferas , Paladio , Ácido Úrico , Ácido Ascórbico/análisis , Ácido Ascórbico/orina , Ácido Úrico/orina , Ácido Úrico/análisis , Dopamina/análisis , Dopamina/orina , Nanosferas/química , Técnicas Electroquímicas/métodos , Carbono/química , Paladio/química , Porosidad , Humanos , Electrodos , Técnicas Biosensibles/métodos , Reproducibilidad de los Resultados
6.
Chemosphere ; 361: 142522, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38838869

RESUMEN

Selecting safe, non-toxic, and non-metallic semiconductor materials that facilitate the degradation of pollutants in water stands out as an optimal approach to combat environmental pollution. Herein, graphitic carbon nitride (g-C3N4)-based hollow nanospheres nonmetallic photocatalyst modified with covalent organic framework materials named TpMA, based on 1, 3, 5-trimethylchloroglucuronide (Tp) and melamine (MA), was successfully synthesized (abbreviated as CNTP). The ordered electron donor-acceptor structure inherent in TpMA contributed to enhancing the transport efficiency of photogenerated carriers in CNTP. The CNTP photocatalysts exhibited excellent performance in degrading rhodamine B and tetracycline in visible light, with optimal degradation rates reached more than 90% in 60 and 80 min, respectively, which were 5.3 and 3.0 times higher than those of pure CNNS. The increased photocatalytic efficiency observed in CNTP composites could be traced back to the covalently connection between the two molecules, forming a π-conjugated system that facilitated the separative efficiency of photogenerated electron-hole pairs and intensified the utilization of visible light. This study provided a new means to design and fabricate highly efficient and environmentally friendly non-metallic photocatalytic materials.


Asunto(s)
Grafito , Nanosferas , Compuestos de Nitrógeno , Rodaminas , Triazinas , Contaminantes Químicos del Agua , Nanosferas/química , Catálisis , Triazinas/química , Grafito/química , Rodaminas/química , Compuestos de Nitrógeno/química , Contaminantes Químicos del Agua/química , Luz , Tetraciclina/química , Nitrilos/química , Procesos Fotoquímicos , Fotólisis
7.
Int J Mol Sci ; 25(10)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38791262

RESUMEN

Orthodontic space closure following tooth extraction is often hindered by alveolar bone deficiency. This study investigates the therapeutic use of nuclear factor-kappa B (NF-κB) decoy oligodeoxynucleotides loaded with polylactic-co-glycolic acid nanospheres (PLGA-NfDs) to mitigate alveolar bone loss during orthodontic tooth movement (OTM) following the bilateral extraction of maxillary first molars in a controlled experiment involving forty rats of OTM model with ethics approved. The decreased tendency of the OTM distance and inclination angle with increased bone volume and improved trabecular bone structure indicated minimized alveolar bone destruction. Reverse transcription-quantitative polymerase chain reaction and histomorphometric analysis demonstrated the suppression of inflammation and bone resorption by downregulating the expression of tartrate-resistant acid phosphatase, tumor necrosis factor-α, interleukin-1ß, cathepsin K, NF-κB p65, and receptor activator of NF-κB ligand while provoking periodontal regeneration by upregulating the expression of alkaline phosphatase, transforming growth factor-ß1, osteopontin, and fibroblast growth factor-2. Importantly, relative gene expression over the maxillary second molar compression side in proximity to the alveolus highlighted the pharmacological effect of intra-socket PLGA-NfD administration, as evidenced by elevated osteocalcin expression, indicative of enhanced osteocytogenesis. These findings emphasize that locally administered PLGA-NfD serves as an effective inflammatory suppressor and yields periodontal regenerative responses following tooth extraction.


Asunto(s)
Nanosferas , Oligodesoxirribonucleótidos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Técnicas de Movimiento Dental , Alveolo Dental , Animales , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Ratas , Nanosferas/química , Técnicas de Movimiento Dental/métodos , Oligodesoxirribonucleótidos/farmacología , Oligodesoxirribonucleótidos/administración & dosificación , Alveolo Dental/efectos de los fármacos , Alveolo Dental/patología , Masculino , FN-kappa B/metabolismo , Cicatrización de Heridas/efectos de los fármacos , Pérdida de Hueso Alveolar/terapia , Pérdida de Hueso Alveolar/patología , Pérdida de Hueso Alveolar/tratamiento farmacológico , Pérdida de Hueso Alveolar/metabolismo , Extracción Dental
8.
Talanta ; 276: 126234, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38749161

RESUMEN

Glutathione (GSH) is an essential antioxidant in the human body, but its detection is difficult due to the interference of complex components in serum. Herein, hollow double-layer Pt@CeO2 nanospheres were developed as oxidase mimetics, and the light-assisted oxidase mimetics effects were found. The oxidase activity was enhanced significantly by utilizing the synergistic effect of Schottky junction and the localized surface plasmon resonance (LSPR) of Pt under UV light. A novel GSH colorimetric-fluorescent-SERS sensing platform was established, with the sensing performance notably boosted by using the light-assisted oxidase mimetics effects. This platform boasts an exceptionally low detection limit (LOD) of 0.084 µM, while the detection time was shortened from 10 min to just 2 min. The anti-interference detection with high recovery rate (96.84%-107.4 %) in real serum made it be promising for practical application.


Asunto(s)
Cerio , Colorimetría , Glutatión , Nanosferas , Oxidorreductasas , Platino (Metal) , Resonancia por Plasmón de Superficie , Glutatión/sangre , Glutatión/química , Colorimetría/métodos , Platino (Metal)/química , Humanos , Cerio/química , Nanosferas/química , Oxidorreductasas/química , Resonancia por Plasmón de Superficie/métodos , Límite de Detección , Materiales Biomiméticos/química , Espectrometría de Fluorescencia/métodos
9.
Mikrochim Acta ; 191(6): 333, 2024 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753167

RESUMEN

The COVID-19 pandemic has underscored the urgent need for rapid and reliable strategies for early detection of SARS-CoV-2. In this study, we propose a DNA nanosphere-based crosslinking catalytic hairpin assembly (CCHA) system for the rapid and sensitive SARS-CoV-2 RNA detection. The CCHA system employs two DNA nanospheres functionalized with catalytic hairpin assembly (CHA) hairpins. The presence of target SARS-CoV-2 RNA initiated the crosslinking of DNA nanospheres via CHA process, leading to the amplification of fluorescence signals. As a result, the speed of SARS-CoV-2 diagnosis was enhanced by significantly increasing the local concentration of the reagents in a crosslinked DNA product, leading to a detection limit of 363 fM within 5 min. The robustness of this system has been validated in complex environments, such as fetal bovine serum and saliva. Hence, the proposed CCHA system offers an efficient and simple approach for rapid detection of SARS-CoV-2 RNA, holding substantial promise for enhancing COVID-19 diagnosis.


Asunto(s)
COVID-19 , Límite de Detección , ARN Viral , SARS-CoV-2 , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , ARN Viral/análisis , ARN Viral/genética , Humanos , COVID-19/diagnóstico , COVID-19/virología , Nanosferas/química , ADN/química , Secuencias Invertidas Repetidas , Animales , Prueba de Ácido Nucleico para COVID-19/métodos , Bovinos , Reactivos de Enlaces Cruzados/química , Saliva/virología
10.
Talanta ; 276: 126235, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38761654

RESUMEN

N-nitrosamines (NAs) are highly carcinogenic compounds commonly found in food, beverages, and consumer products. Due to their wide polarity range, it is challenging to find a suitable carbon adsorbent that can simultaneously adsorb and enrich both polar and nonpolar NAs with good recovery. In this study, nitrogen-doped magnetic mesoporous carbon nanospheres (M-MCN) were prepared and employed as an adsorbent for magnetic solid-phase extraction (MSPE) to extract and concentrate four NAs. The introduction of nitrogen functional groups enhanced the hydrophilicity of the carbon material, allowing M-MCN to achieve a balance between hydrophilicity and hydrophobicity, resulting in good recovery for both polar and nonpolar NAs. A method combining MSPE with gas chromatography-mass spectrometry (GC-MS) was developed for the determination of NAs in processed meat and alcoholic beverages. The method exhibited a good linear range (1-100 ng g-1, r2 > 0.9967) and trace-level detection (0.53-6.6 ng g-1). The recovery rates for the four NAs ranged between 85.7 and 110.7 %, with intra-day precision expressed as relative standard deviation (RSD) between 4.1 and 10.7 %, and inter-day precision between 4.8 and 12.9 %. The results demonstrated not only good accuracy and precision but also provided a new adsorbent for the enrichment of trace-level NAs in processed meat and alcoholic beverage samples.


Asunto(s)
Carbono , Cromatografía de Gases y Espectrometría de Masas , Indoles , Nanosferas , Nitrógeno , Nitrosaminas , Polímeros , Extracción en Fase Sólida , Nitrógeno/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Porosidad , Nanosferas/química , Carbono/química , Polímeros/química , Nitrosaminas/análisis , Nitrosaminas/aislamiento & purificación , Indoles/química , Extracción en Fase Sólida/métodos , Adsorción , Óxido Ferrosoférrico/química
11.
Dent Mater ; 40(7): 1078-1087, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38797613

RESUMEN

OBJECTIVES: Composites with copper-doped mesoporous bioactive nanospheres (Cu-MBGN) were developed to prevent secondary caries by imparting antimicrobial and ion-releasing/remineralizing properties. METHODS: Seven experimental composites containing 1, 5 or 10 wt% Cu-MBGN, the corresponding inert controls (silica) and bioactive controls (bioactive glass 45S5) were prepared. The temperature rise during light curing, cross-linking density by ethanol softening test, monomer elution and their potential adverse effects on the early development of zebrafish Danio rerio was investigated. RESULTS: Materials combining Cu-MBGN and silica showed the highest resistance to ethanol softening, as did the bioactive controls. Cu-MBGN composites showed significant temperature rise and reached maximum temperature in the shortest time. Bisphenol A was not detected, while bis-GMA was found only in the control materials and TEGDMA in the eluates of all materials. There was no increase in zebrafish mortality and abnormality rates during exposure to the eluates of any of the materials. CONCLUSIONS: The composite with 5 wt% Cu-MBGN combined with nanosilica fillers showed the lowest ethanol softening, indicating the polymer's highest durability and cross-linking density. Despite the TEGDMA released from all tested materials, no embryotoxic effect was observed.


Asunto(s)
Resinas Compuestas , Cobre , Nanosferas , Polimerizacion , Pez Cebra , Animales , Nanosferas/química , Nanosferas/toxicidad , Cobre/química , Cobre/toxicidad , Resinas Compuestas/química , Resinas Compuestas/toxicidad , Porosidad , Ensayo de Materiales , Embrión no Mamífero/efectos de los fármacos , Reactivos de Enlaces Cruzados/química , Dióxido de Silicio/química , Dióxido de Silicio/toxicidad , Temperatura , Compuestos de Bencidrilo/toxicidad , Compuestos de Bencidrilo/química , Etanol/química , Fenoles
12.
Anal Chim Acta ; 1306: 342598, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692791

RESUMEN

BACKGROUND: Carbon-based nanozymes have recently received enormous concern, however, there is still a huge challenge for inexpensive and large-scale synthesis of magnetic carbon-based "Two-in-One" mimics with both peroxidase (POD)-like and laccase-like activities, especially their potential applications in multi-mode sensing of antibiotics and neurotransmitters in biofluids. Although some progresses have been made in this field, the feasibility of biomass-derived carbon materials with both POD-like and laccase-like activities by polyatomic doping strategy is still unclear. In addition, multi-mode sensing platform can provide a more reliable result because of the self-validation, self-correction and mutual agreement. Nevertheless, the use of magnetic carbon-based nanozyme sensors for the multi-mode detection of antibiotics and neurotransmitters have not been investigated. RESULTS: We herein report a shrimp shell-derived N, O-codoped porous carbon confined magnetic CuFe2O4 nanosphere with outstanding laccase-like and POD-like activities for triple-mode sensing of antibiotic d-penicillamine (D-PA) and chloramphenicol (CPL), as well as colorimetric detection of neurotransmitters in biofluids. The magnetic CuFe2O4/N, O-codoped porous carbon (MCNPC) armored mimetics was successfully fabricated using a combined in-situ coordination and high-temperature crystallization method. The synthesized MCNPC composite with superior POD-like activity can be used for colorimetric/temperature/smartphone-based triple-mode detection of D-PA and CPL in goat serum. Importantly, the MCNPC nanozyme can also be used for colorimetric analysis of dopamine and epinephrine in human urine. SIGNIFICANCE: This work not only offered a novel strategy to large-scale, cheap synthesize magnetic carbon-based "Two-in-One" armored mimetics, but also established the highly sensitive and selective platforms for triple-mode monitoring D-PA and CPL, as well as colorimetric analysis of neurotransmitters in biofluids without any tanglesome sample pretreatment.


Asunto(s)
Antibacterianos , Carbono , Cobre , Neurotransmisores , Carbono/química , Antibacterianos/análisis , Antibacterianos/orina , Antibacterianos/sangre , Neurotransmisores/orina , Neurotransmisores/análisis , Neurotransmisores/sangre , Porosidad , Cobre/química , Humanos , Nanosferas/química , Colorimetría/métodos , Compuestos Férricos/química , Materiales Biomiméticos/química , Animales , Técnicas Biosensibles/métodos , Cloranfenicol/análisis , Cloranfenicol/orina , Límite de Detección
13.
Anal Chim Acta ; 1310: 342716, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811135

RESUMEN

BACKGROUND: Assembling framework nucleic acid (FNA) nanoarchitectures and tuning luminescent quantum dots (QDs) for fluorescence assays represent a versatile strategy in analytical territory. Rationally, FNA constructs could offer a preferential orientation to efficiently recognize the target and improve detection sensitivity, meanwhile, regulating size-dependent multicolor emissions of QDs in one analytical setting for ratiometric fluorescence assay would greatly simplify operation procedures. Nonetheless, such FNA/QDs-based ratiometric fluorescence nanoprobes remain rarely explored. RESULTS: We designed a sensitive and signal amplification-free fluorescence aptasensor for lead ions (Pb2+) that potentially cause extensive contamination to environment, cosmetic, food and pharmaceuticals. Red and green emission CdTe quantum dots (rQDs and gQDs) were facilely prepared. Moreover, silica nanosphere encapsulating rQDs served as quantitative internal reference and scaffold to anchor a predesigned FNA and DNA sandwich containing Pb2+ binding aptamer and gQD modified DNA signal reporter. On binding of Pb2+, the gQD-DNA signal reporter was set free, resulting in fluorescence quenching at graphene oxide (GO) interface. Owing to the rigid structure of FNA, the fluorescence signal reporter orderly arranged at the silica nanosphere could sensitively respond to Pb2+ stimulation. The dose-dependent fluorescence signal-off mode enabled ratiometric analysis of Pb2+ without cumbersome signal amplification. Linear relationship was established between fluorescence intensity ratio (I555/I720) and Pb2+ concentration from 10 nM to 2 µM, with detection limit of 1.7 nM (0.43 ppb), well addressing the need for Pb2+ routine monitoring. The designed nanoprobe was applied to detection of Pb2+ in soil, cosmetic, milk, drug, and serum samples, with the sensitivity comparable to conventional ICP-MS technique. SIGNIFICANCE: Given the programmable design of FNA and efficient recognition of target, flexible tuning of QDs emission, and signal amplification-free strategy, the present fluorescence nanoprobe could be a technical criterion for other heavy metal ions detection in a straightforward manner.


Asunto(s)
ADN , Grafito , Plomo , Nanosferas , Puntos Cuánticos , Dióxido de Silicio , Espectrometría de Fluorescencia , Puntos Cuánticos/química , Plomo/análisis , Plomo/química , Grafito/química , Dióxido de Silicio/química , Nanosferas/química , ADN/química , Compuestos de Cadmio/química , Límite de Detección , Telurio/química , Aptámeros de Nucleótidos/química , Fluorescencia , Técnicas Biosensibles/métodos
14.
Food Chem ; 452: 139595, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38749143

RESUMEN

Selenium nanospheres (SeNPs) show less toxicity and greater bioavailability than selenite salts. This research demonstrated the substantial tolerance and efficient conversion of Se(IV) into SeNPs by Lactiplantibacillus plantarum NML21. The bioreduction process of Se(IV) and the properties of SeNPs, including their morphology, particle size, and stability, were investigated with techniques including SEM, EDX, TEM, XPS, FT-IR, dynamic light scattering, XRD, and Raman spectroscopy. Under high selenium stress, certain cells displayed significant deformation and rupture, and released SeNPs as the main product of the bioreduction of Se(IV). These SeNPs were red, amorphous, zero-valent, and spherical, with an average diameter of 160 nm. Spectroscopic analysis highlighted that the functional groups of CO and CO are key to the bioreduction of Se(IV). The study suggested preliminary mechanisms for the bioreduction of Se(IV) and the formation and release of SeNPs by lactic acid bacteria. NML21 may therefore be a promising candidate for SeNPs synthesis.


Asunto(s)
Nanosferas , Oxidación-Reducción , Selenio , Selenio/química , Selenio/metabolismo , Nanosferas/química , Nanosferas/metabolismo , Tamaño de la Partícula , Lactobacillus plantarum/metabolismo , Lactobacillus plantarum/química
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 317: 124399, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38718747

RESUMEN

Herein, a novel sandwich electrochemiluminescence (ECL) aptasensor was developed based on the resonance energy transfer (RET) with iridium complex doped silicate nanoparticles (SiO2@Ir) as energy donor and gold nanoparticles modified TiVC MXene (AuNPs@TiVC) as energy acceptor. Strong anodic ECL signal of SiO2@Ir was obtained through both co-reactant pathway and annihilation pathway. Electrochemical results showed that SiO2@Ir has good electron transfer rate and large specific surface area to immobilize more aptamers. AuNPs@TiVC apparently quenched the ECL signal of SiO2@Ir due to the ECL resonance energy transfer between them. In the presence of kanamycin (KAN), a sandwich type sensor was formed with the aptamer probes as connecters between the donor and the acceptor, resulting in the decrease of ECL intensity. Under the optimal condition, KAN could be sensitively detected in the range of 0.1 pg/mL to 10 ng/mL with a low detection limit of 24.5 fg/mL. The proposed ECL system exhibited satisfactory analytical performance, which can realize the detection of various biological molecules by adopting suitable aptamer.


Asunto(s)
Técnicas Electroquímicas , Oro , Iridio , Kanamicina , Límite de Detección , Nanopartículas del Metal , Dióxido de Silicio , Dióxido de Silicio/química , Oro/química , Nanopartículas del Metal/química , Iridio/química , Técnicas Electroquímicas/métodos , Kanamicina/análisis , Mediciones Luminiscentes/métodos , Nanosferas/química , Aptámeros de Nucleótidos/química , Titanio/química , Técnicas Biosensibles/métodos , Transferencia de Energía
16.
Antiviral Res ; 226: 105900, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38705200

RESUMEN

BACKGROUND & AIMS: The spread of foot-and-mouth disease virus (FMDV) through aerosol droplets among cloven-hoofed ungulates in close contact is a major obstacle for successful animal husbandry. Therefore, the development of suitable mucosal vaccines, especially nasal vaccines, to block the virus at the initial site of infection is crucial. PATIENTS AND METHODS: Here, we constructed eukaryotic expression plasmids containing the T and B-cell epitopes (pTB) of FMDV in tandem with the molecular mucosal adjuvant Fms-like tyrosine kinase receptor 3 ligand (Flt3 ligand, FL) (pTB-FL). Then, the constructed plasmid was electrostatically attached to mannose-modified chitosan-coated poly(lactic-co-glycolic) acid (PLGA) nanospheres (MCS-PLGA-NPs) to obtain an active nasal vaccine targeting the mannose-receptor on the surface of antigen-presenting cells (APCs). RESULTS: The MCS-PLGA-NPs loaded with pTB-FL not only induced a local mucosal immune response, but also induced a systemic immune response in mice. More importantly, the nasal vaccine afforded an 80% protection rate against a highly virulent FMDV strain (AF72) when it was subcutaneously injected into the soles of the feet of guinea pigs. CONCLUSIONS: The nasal vaccine prepared in this study can effectively induce a cross-protective immune response against the challenge with FMDV of same serotype in animals and is promising as a potential FMDV vaccine.


Asunto(s)
Administración Intranasal , Quitosano , Virus de la Fiebre Aftosa , Fiebre Aftosa , Nanosferas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Vacunas Virales , Animales , Quitosano/química , Quitosano/administración & dosificación , Virus de la Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/genética , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Ratones , Nanosferas/química , Vacunas Virales/inmunología , Vacunas Virales/administración & dosificación , Ratones Endogámicos BALB C , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Femenino , Ácidos Nucleicos/administración & dosificación , Inmunidad Mucosa , Sistemas de Liberación de Medicamentos
17.
ACS Sens ; 9(4): 2183-2193, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38588327

RESUMEN

Sensitive and selective acetone detection is of great significance in the fields of environmental protection, industrial production, and individual health monitoring from exhaled breath. To achieve this goal, bimetallic Au@Pt core-shell nanospheres (BNSs) functionalized-electrospun ZnFe2O4 nanofibers (ZFO NFs) are prepared in this work. Compared to pure NFs-650 analogue, the ZFO NFs/BNSs-2 sensor exhibits a stronger mean response (3.32 vs 1.84), quicker response/recovery speeds (33 s/28 s vs 54 s/42 s), and lower operating temperature (188 vs 273 °C) toward 0.5 ppm acetone. Note that an experimental detection limit of 30 ppb is achieved, which ranks among the best cases reported thus far. Besides the demonstrated excellent repeatability, humidity-enhanced response, and long-term stability, the selectivity toward acetone is remarkably improved after BNSs functionalization. Through material characterizations and DFT calculations, all these improvements could be attributed to the boosted oxygen vacancies and abundant Schottky junctions between ZFO NFs and BNSs, and the synergistic catalytic effect of BNSs. This work offers an alternative strategy to realize selective subppm acetone under high-humidity conditions catering for the future requirements of noninvasive breath diabetes diagnosis in the field of individual healthcare.


Asunto(s)
Acetona , Pruebas Respiratorias , Oro , Nanofibras , Nanosferas , Platino (Metal) , Acetona/análisis , Acetona/química , Nanofibras/química , Oro/química , Pruebas Respiratorias/métodos , Nanosferas/química , Platino (Metal)/química , Humanos , Límite de Detección , Oxígeno/química , Técnicas Electroquímicas/métodos
18.
J Chromatogr A ; 1724: 464910, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38657316

RESUMEN

A simplified approach for preparation of sandwich type molecularly imprinted polymers (PPDA-MIPs) is proposed for simultaneously identify Low-density lipoprotein (LDL) and dispose "bad cholesterol". Porous polydopamine nanosphere (PPDA) is applied as a matrix for immobilization of LDL, and the imprinted layer is formed by dopamine acting as a functional monomer. Since imprinted cavities exhibit shape memory effects in terms of recognizing selectivity, the PPDA-MIPs exhibit excellent selectivity toward LDL and a substantial binding capacity of 550.3 µg mg-1. Meanwhile, six adsorption/desorption cycles later, the adsorption efficiency of 83.09 % is still achieved, indicating the adequate stability and reusability of PPDA-MIPs. Additionally, over 80 % of cholesterol is recovered, indicating the completeness of "bad cholesterol" removal in LDL. Lastly, as demonstrated by gel electrophoresis, PPDA-MIPs performed satisfactory behavior for the removal of LDL from the goat serum sample.


Asunto(s)
Colesterol , Indoles , Lipoproteínas LDL , Polímeros Impresos Molecularmente , Polímeros , Lipoproteínas LDL/sangre , Lipoproteínas LDL/química , Lipoproteínas LDL/aislamiento & purificación , Adsorción , Polímeros/química , Colesterol/sangre , Colesterol/química , Indoles/química , Animales , Polímeros Impresos Molecularmente/química , Dopamina/sangre , Dopamina/química , Dopamina/aislamiento & purificación , Dopamina/análisis , Impresión Molecular/métodos , Cabras , Nanosferas/química
19.
Biochem Biophys Res Commun ; 714: 149976, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38677007

RESUMEN

BACKGROUND: The systemic treatment of advanced hepatocellular carcinoma is currently facing a bottleneck. EGCG, the primary active compound in green tea, exhibits anti-tumor effects through various pathways. However, there is a lack of study on EGCG-induced immunogenic cell death (ICD) in hepatocellular carcinoma. METHODS: In a previous study, we successfully synthesized folate-modified thermosensitive nano-materials, encapsulated EGCG within nanoparticles using a hydration method, and established the EGCG nano-drug delivery system. The viability of HepG2 cells post-EGCG treatment was assessed via the MTT and EdU assays. Cell migration and invasion were evaluated through wound healing experiments, Transwell assays, and Annexin V-FITC/PI assay for apoptosis detection. Additionally, the expression levels of damage-associated molecular patterns (DAMPs) were determined using immunofluorescence, ATP measurement, RT-qPCR, and Western Blot. RESULTS: The drug sensitivity test revealed an IC50 value of 96.94 µg/mL for EGCG in HepG2 cells after 48 h. EGCG at a low concentration (50 µg/mL) significantly impeded the migration and invasion of HepG2 cells, showing a clear dose-dependent response. Moreover, medium to high EGCG concentrations induced cell apoptosis in a dose-dependent manner and upregulated DAMPs expression. Immunofluorescence analysis demonstrated a notable increase in CRT expression following low-concentration EGCG treatment. As EGCG concentration increased, cell viability decreased, leading to CRT exposure on the cell membrane. EGCG also notably elevated ATP levels. RT-qPCR and Western Blot analyses indicated elevated expression levels of HGMB1, HSP70, and HSP90 following EGCG intervention. CONCLUSION: EGCG not only hinders the proliferation, migration, and invasion of hepatocellular carcinoma cells and induces apoptosis, but also holds significant clinical promise in the treatment of malignant tumors by promoting ICD and DAMPs secretion.


Asunto(s)
Carcinoma Hepatocelular , Catequina , Catequina/análogos & derivados , Ácido Fólico , Neoplasias Hepáticas , Humanos , Catequina/farmacología , Catequina/química , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Células Hep G2 , Ácido Fólico/química , Ácido Fólico/farmacología , Movimiento Celular/efectos de los fármacos , Muerte Celular Inmunogénica/efectos de los fármacos , Nanosferas/química , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Temperatura , Calreticulina/metabolismo
20.
Chemosphere ; 357: 142033, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38615961

RESUMEN

The design and preparation of dual-functional photocatalysts for simultaneously realizing photocatalytic wastewater purification and hydrogen energy generation pose significant challenges. This article presents the engineering of a binary heterostructured photocatalyst by combining TiO2 (nanorods) and MoS2 nanosphere using a straightforward solvothermal method and the assessment of the phase structures, morphologies, and optical properties of the resulting nanocomposites using diverse analytical techniques. The TiO2(Rod)/MoS2 composite exhibits remarkable efficacy in degrading ciprofloxacin, achieving 93% removal rate within 1 h, which is four times higher than that of bare TiO2. Moreover, the optimized TiO2(Rod)/MoS2 presents an outstanding hydrogen production rate of 7415 µmol g-1, which is ∼24 times higher than that of pristine TiO2. Under UV-visible light irradiation, the TiO2(Rod)/MoS2 heterojunction displays an exceptional photocatalytic performance in terms of both photodegradation and hydrogen production, surpassing the performance of TiO2 particle/MoS2. The study findings demonstrate that TiO2(Rod)/MoS2 nanocomposites exhibit considerably improved photocatalytic degradation and hydrogen generation activities. Based on the experimental results, a possible mechanism is proposed for the transfer and separation of charge carriers in Z-scheme heterojunctions.


Asunto(s)
Antibacterianos , Disulfuros , Hidrógeno , Molibdeno , Nanosferas , Nanotubos , Titanio , Titanio/química , Molibdeno/química , Catálisis , Antibacterianos/química , Nanosferas/química , Hidrógeno/química , Disulfuros/química , Nanotubos/química , Nanocompuestos/química , Fotólisis , Contaminantes Químicos del Agua/química , Aguas Residuales/química , Ciprofloxacina/química
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