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1.
Int J Nanomedicine ; 16: 2477-2486, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33824586

RESUMEN

Purpose: Sensitive and selective point-of-care biosensor is an urgent pursuit of serological antibody detection to control parasite pathogen. For specific, quantitative and on-site screening of Trichinella spiralis infection in livestock, a quantum dot nanobead-monoclonal antibody (QB-mAb) probe-based immunochromatographic assay (ICA) was developed by introducing a competitive sandwich strategy (QB-CICA). Methods: In the QB-CICA, QB-mAb probes competed with serum antibody for a particular epitope, followed by immunocomplexes binding to capture antibody on the test line. With the accumulation of target antibody, captured probes served as signal elements for fluorescent readout in a "turn off" mode, along with the fluorescence gradually weakened. The sensitivity and standard calibration curve of the QB-CICA were quantified using swine sera as negative control (n = 200) and artificial infected swine sera (n = 80) compared with a commercial ELISA kit. Besides, Trichinella spiralis-antibody targeting test ability of the QB-CICA, instead of other parasites or viruses antibodies (n = 10), was evaluated. Results: The QB-CICA exhibited a good linear range, a low detection limit of 189.92 ng mL-1 and 100% selectivity that was higher than commercial ELISA kit (90%), as well as the same serological positive rate (100%) with commercial ELISA kit in different infection dose models. Conclusion: Taking advantage of its simplicity, short response time (25 min), sensitivity and specificity, the proposed QB-CICA has potential applications for parasite-related antibody monitoring in food safety and clinical diagnosis fields.


Asunto(s)
Anticuerpos Antihelmínticos/análisis , Anticuerpos Monoclonales/inmunología , Cromatografía de Afinidad/métodos , Nanopartículas/química , Puntos Cuánticos/química , Trichinella spiralis/inmunología , Triquinelosis/diagnóstico , Triquinelosis/inmunología , Animales , Anticuerpos Antihelmínticos/sangre , Anticuerpos Antihelmínticos/inmunología , Nanopartículas/ultraestructura , Puntos Cuánticos/ultraestructura , Porcinos , Triquinelosis/parasitología
2.
Molecules ; 26(6)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33802020

RESUMEN

Glycyrrhizae Radix et Rhizoma (GRR) is one of the commonly used traditional Chinese medicines in clinical practice, which has been applied to treat digestive system diseases for hundreds of years. GRR is preferred for anti-gastric ulcer, however, the main active compounds are still unknown. In this study, GRR was used as precursor to synthesize carbon dots (CDs) by a environment-friendly one-step pyrolysis process. GRR-CDs were characterized by using transmission electron microscopy, high-resolution TEM, fourier transform infrared, ultraviolet-visible and fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. In addition, cellular toxicity of GRR-CDs was studied by using CCK-8 in RAW264.7 cells, and the anti-gastric ulcer activity was evaluated and confirmed using mice model of acute alcoholic gastric ulcer. The experiment confirmed that GRR-CDs were the spherical structure with a large number of active groups on the surface and their particle size ranged from 2 to 10 nm. GRR-CDs had no toxicity to RAW264.7 cells at concentration of 19.5 to 5000 µg/mL and could reduce the oxidative damage of gastric mucosa and tissues caused by alcohol, as demonstrated by restoring expression of malondialdehyde, superoxide dismutase and nitric oxide in serum and tissue of mice. The results indicated the explicit anti-ulcer activity of GRR-CDs, which provided a new insights for the research on effective material basis of GRR.


Asunto(s)
Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Puntos Cuánticos/química , Animales , Carbono/química , China , Cromatografía Líquida de Alta Presión/métodos , Glycyrrhiza/química , Masculino , Medicina China Tradicional/métodos , Ratones , Espectroscopía de Fotoelectrones/métodos , Pirólisis , Células RAW 264.7 , Espectrometría de Fluorescencia/métodos
3.
Food Chem ; 354: 129536, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-33756326

RESUMEN

Arginine kinase (AK) is one of the most important allergens in shrimp products. Herein, a novel immunoassay for quantitation of AK was developed using the antibody modified gold nanoparticle (AuNP) and quantum dot (QD). When the first antibody modified AuNP (AuNP-Ab1) was bridged by AK with the secondary antibody modified QD (QD-Ab2), fluorescence resonance energy transfer (FRET) would occur between the AuNP and QD, which led to a decrease in fluorescent signals. The decrease in fluorescence intensity was found to correlate linearly with the log of AK concentration in the range of 1.0 × 10-6-1.0 × 10-3 mg/mL (R2 = 0.9909) and the detection limit was 0.11 ng/mL. The immunoassay was further proved to have encouraging specificity, precision and accuracy. Compared with existing methods, this study provided a promising approach to develop a highly sensitive and selective detection method for AK in shrimp related food samples.


Asunto(s)
Arginina Quinasa/análisis , Transferencia Resonante de Energía de Fluorescencia , Oro/química , Inmunoensayo/métodos , Nanopartículas del Metal/química , Puntos Cuánticos/química , Sulfuros/química , Compuestos de Zinc/química , Límite de Detección , Alimentos Marinos
4.
Carbohydr Polym ; 259: 117753, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33674007

RESUMEN

A new type of nanocellulose/poly(vinyl alcohol)/carbon dot (NPC) multifunctional hydrogel was successfully fabricated by an one-step in-situ hydrothermal method. The one-pot strategy led to the formation of a complex hydrogen bonding/dynamic boric acid ester/nitrogen-doped carbon dots network, and endowed the hydrogel with multifunctionality. The hydrogel underwent self-healing at room temperature (25 °C) and exhibited double-emission fluorescence and high mechanical strength (tensile strength of up to 2.98 MPa). An NPC hydrogel-based capacitive sensor exhibited remarkable linear capacitance responsiveness toward pressure, strain, and glucose concentration, and enabled real-time synchronous quantitative pressure/glucose sensing with multiple linear correlations, which was a key performance criteria for biomechanical sensors. The versatility and multiple advantages of the as-prepared hydrogel demonstrate the potential of biological-mechanical sensing materials using natural cellulosic biomass.


Asunto(s)
Técnicas Biosensibles/métodos , Celulosa/química , Hidrogeles/química , Alcohol Polivinílico/química , Puntos Cuánticos/química , Materiales Biocompatibles/química , Carbono/química , Glucosa/análisis , Enlace de Hidrógeno , Temperatura , Resistencia a la Tracción
5.
Food Chem ; 352: 129352, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33691206

RESUMEN

A ratiometric fluorescence sensor system is proposed for detecting bis(2-ethylhexyl) phthalate (DEHP) in pork, which is based on aptamer recognition with molybdenum disulfide quantum dots and cadmium telluride quantum dots (MoS2 QDs/CdTe-Apta). Two signals exist in the system, among which the response signal is transmitted by CdTe-Apta. The amide condensation between aptamers and CdTe QDs shortens the distance between CdTe QDs and DEHP, thus quenching the fluorescence of CdTe QDs, possibly through a photoinduced electron transfer mechanism. The MoS2 QDs deliver the self-calibration signal, and the fluorescence of MoS2 QDs remains almost constant when co-existing with DEHP. Linearity (R2 = 0.9536) was established for the DEHP concentration range 0.005-3.0 mg·L-1, with a limit of detection of 0.21 µg·L-1. The system was successfully applied in the determination of DEHP in pork. The system has potential for the quantitative determination of DEHP in practical applications.


Asunto(s)
Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/metabolismo , Técnicas Biosensibles/métodos , Dietilhexil Ftalato/análisis , Carne de Cerdo/análisis , Animales , Compuestos de Cadmio/química , Dietilhexil Ftalato/metabolismo , Disulfuros/química , Molibdeno/química , Puntos Cuánticos/química , Espectrometría de Fluorescencia , Porcinos , Telurio/química
6.
Carbohydr Polym ; 260: 117806, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712152

RESUMEN

Chitin-encapsulated cadmium sulfide quantum dots (CdS@CTN QDs) were successfully synthesized from chitin and Cd(NO3)2 precursor using the colloidal chemistry method, toward the development of biocompatible and biodegradable QDs for biomedical applications. CdS@CTN QDs exhibited the nanocrystalline cubic CdS encapsulated by α-chitin. The average particle size of CdS@CTN QDs was estimated using empirical Henglein model to be 3.9 nm, while their crystallite size was predicted using Scherrer equation to be 4.3 nm, slightly larger compared to 3-mercaptopropionic acid-capped CdS QDs (3.2 and 3.6 nm, respectively). The mechanism of formation was interpreted based on the spectroscopic data and X-ray crystal structures of CdS@CTN QDs fabricated at different pH values and mass ratios of chitin to Cd(NO3)2 precursor. As an important step to explore potential biomolecular and biological applications of CdS@CTN QDs, their antibacterial activities were tested against four different bacterial strains; i.e. Escherichia coli, Bacillus subtillus, Staphylococcus aureus and Pseudomonas aeruginosa.


Asunto(s)
Antibacterianos/química , Materiales Biocompatibles/química , Quitina/química , Puntos Cuánticos/química , Antibacterianos/farmacología , Materiales Biocompatibles/farmacología , Compuestos de Cadmio/química , Escherichia coli/efectos de los fármacos , Tamaño de la Partícula , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Sulfuros/química
7.
Molecules ; 26(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33669142

RESUMEN

Water-soluble fluorescent carbon dots (CDs) were synthesized by a hydrothermal method using citric acid as the carbon source and ethylenediamine as the nitrogen source. The repeated and scale-up synthetic experiments were carried out to explore the feasibility of macroscopic preparation of CDs. The CDs/Fe3+ composite was prepared by the interaction of the CDs solution and Fe3+ solution. The optical properties, pH dependence and stability behavior of CDs or the CDs/Fe3+ composite were studied by ultraviolet spectroscopy and fluorescence spectroscopy. Following the principles of fluorescence quenching after the addition of Fe3+ and then the fluorescence recovery after the addition of asorbic acid, the fluorescence intensity of the carbon dots was measured at λex = 360 nm, λem = 460 nm. The content of ascorbic acid was calculated by quantitative analysis of the changing fluorescence intensity. The CDs/Fe3+ composite was applied to the determination of different active molecules, and it was found that the composite had specific recognition of ascorbic acid and showed an excellent linear relationship in 5.0-350.0 µmol·L-1. Moreover, the detection limit was 3.11 µmol·L-1. Satisfactory results were achieved when the method was applied to the ascorbic acid determination in jujube fruit. The fluorescent carbon dots composites prepared in this study may have broad application prospects in a rapid, sensitive and trace determination of ascorbic acid content during food processing.


Asunto(s)
Ácido Ascórbico/análisis , Carbono/química , Colorantes Fluorescentes/química , Puntos Cuánticos/química , Colorantes Fluorescentes/síntesis química , Frutas/química , Ziziphus/química
8.
Molecules ; 26(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670286

RESUMEN

Organic semiconductor micro/nanocrystals (OSMCs) have attracted great attention due to their numerous advantages such us free grain boundaries, minimal defects and traps, molecular diversity, low cost, flexibility and solution processability. Due to all these characteristics, they are strong candidates for the next generation of electronic and optoelectronic devices. In this review, we present a comprehensive overview of these OSMCs, discussing molecular packing, the methods to control crystallization and their applications to the area of organic solid-state lasers. Special emphasis is given to OSMC lasers which self-assemble into geometrically defined optical resonators owing to their attractive prospects for tuning/control of light emission properties through geometrical resonator design. The most recent developments together with novel strategies for light emission tuning and effective light extraction are presented.


Asunto(s)
Rayos Láser , Compuestos Orgánicos/química , Puntos Cuánticos/química , Cristalización , Humanos , Luz
9.
Int J Nanomedicine ; 16: 1849-1867, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33707943

RESUMEN

Background: With the development of bacterial resistance, the range of effective antibiotics is increasingly becoming more limited. The effective use of nanoscale antimicrobial peptides (AP) in therapeutic and diagnostic methods is a strategy for new antibiotics. Methods: Combining both AP and cadmium selenide (CdSe) into a composite material may result in a reagent with novel properties, such as enhanced antibacterial activity, fluorescence and favorable stability in aqueous solution. Results: AP-loaded CdSe NPs (AP-CdSe NPs) showed strong antibacterial activity against multidrug-resistant (MDR) Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in vitro and in vivo. Colony-forming unit (CFU) and minimum inhibitory concentration (MIC) assays showed that AP-CdSe NPs have highly effective antibacterial activity. The quantitative analysis of apoptosis by flow cytometry analysis further confirmed that MDR E. coli and S. aureus treated with AP-CdSe NPs had death rates of 98.76% and 99.13%, respectively. Also, AP-CdSe NPs was found to inhibit bacterial activity in an in vivo bacteremia model in mice infected with S. aureus. In addition, the antibacterial mechanism of AP-CdSe NPs was determined by RNA sequencing analysis. Gene ontology (GO) analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis revealed the molecular mechanism of the antibacterial effect of AP-CdSe NPs. Importantly, histopathology analysis, and hematological toxicity analysis indicated that AP-CdSe NPs had few side effects. Conclusion: These results demonstrate that AP loaded on CdSe NPs had a higher water solubility, bioavailability and antibacterial effect compared with raw AP. This study reports findings that are helpful for the design and development of antibacterial treatment strategies based on AP.


Asunto(s)
Antibacterianos/farmacología , Compuestos de Cadmio/química , Luminiscencia , Nanopartículas/química , Proteínas Citotóxicas Formadoras de Poros/farmacología , Puntos Cuánticos/química , Compuestos de Selenio/química , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Bacteriemia/microbiología , Recuento de Colonia Microbiana , Modelos Animales de Enfermedad , Endocitosis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/ultraestructura , Femenino , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Ontología de Genes , Ratones Desnudos , Pruebas de Sensibilidad Microbiana , Microscopía Fluorescente , Nanopartículas/ultraestructura , Proteínas Citotóxicas Formadoras de Poros/efectos adversos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/ultraestructura
10.
Int J Nanomedicine ; 16: 2045-2058, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33731993

RESUMEN

Background: Carbon dots (CDs) emitting near-infrared fluorescence were recently synthesized from green leaves. However, the Hg2+ detection of CDs was limited because of the insufficient water solubility, low fluorescence and poor stability. Methods: Dual fluorescence emission water-soluble CD (Dual-CD) was prepared through a solvothermal method from holly leaves and low toxic PEI1.8k. PEG was further grafted onto the surface to improve the water solubility and stability. Results: The Dual-CD solution can emit 487 nm and 676 nm fluorescence under single excitation and exhibit high quantum yield of 16.8%. The fluorescence at 678 nm decreased remarkably while the emission at 470 nm was slightly affected by the addition of Hg2+. The ratiometric Hg2+ detection had a wide linear range of 0-100 µM and low detection limit of 14.0 nM. In A549 cells, there was a good linear relation between F487/F676 and the concentration of Hg2+ in the range of 0-60 µM; the detection limit was 477 nM. Furthermore, Dual-CD showed visual fluorescence change under Hg2+. Conclusion: Dual-CD has ratiometric responsiveness to Hg2+ and can be applied for quantitative Hg2+ detection in living cells.


Asunto(s)
Carbono/química , Ilex/química , Mercurio/análisis , Hojas de la Planta/química , Puntos Cuánticos/química , Agua/química , Células A549 , Supervivencia Celular , Humanos , Iones , Fenómenos Ópticos , Espectroscopía de Fotoelectrones , Puntos Cuánticos/ultraestructura , Espectrometría de Fluorescencia , Espectrofotometría Ultravioleta
11.
Int J Nanomedicine ; 16: 2203-2217, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33762821

RESUMEN

Background: It is well known that smoking is harmful to health; however, it can also ameliorate anxiety. To date, it is unclear whether any nanoparticles found in cigarette mainstream smoke (CS) contribute to this effect. Aim: The aim of this study was to assess the particle composition of CS to identify novel anti-anxiety components. Methods: Carbon dots (CDs) from CS (CS-CDs) were characterised using high-resolution transmission electron microscopy, Fourier-transform infrared, ultraviolet, fluorescence, X-ray photoelectron spectroscopy, X-ray diffraction and high-performance liquid chromatography. The anti-anxiety effects of CS-CDs in mouse models were evaluated and confirmed with the elevated plus maze and open-field tests. Results: The quantum yield of CS-CDs was 13.74%, with a composition of C, O, and N. In addition, the surface groups contained O-H, C-H, C=O, C-N, N-H, C-O-C, and COO- bonds. Acute toxicity testing revealed that CS-CDs had low in vitro and in vivo toxicity within a certain concentration range. The results of the elevated plus maze and open-field tests showed that CS-CDs had a significant anti-anxiety effect and a certain sedative effect in mice. The mechanism of these effects may be related to the decrease in glutamate levels and promotion of norepinephrine production in the mouse brain, and the decrease in dopamine in mouse serum due to CS-CDs. Conclusion: CS-CDs may have anti-anxiety and certain sedative effects. This study provides a new perspective for a more comprehensive understanding of the components, properties, and functions of CS. Furthermore, it offers a novel target for the development of smoking cessation treatments, such as nicotine replacement therapy.


Asunto(s)
Conducta Animal , Carbono/química , Fumar Cigarrillos/efectos adversos , Sistema Endocrino/metabolismo , Neurotransmisores/metabolismo , Puntos Cuánticos/química , Agua/química , Hormona Adrenocorticotrópica/sangre , Animales , Ansiedad/sangre , Ansiedad/patología , Encéfalo/metabolismo , Encéfalo/patología , Cromatografía Líquida de Alta Presión , Corticosterona/sangre , Hormona Liberadora de Corticotropina/sangre , Dopamina/sangre , Masculino , Ratones , Ratones Endogámicos ICR , Espectroscopía de Fotoelectrones , Puntos Cuánticos/ultraestructura , Células RAW 264.7 , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Pruebas de Toxicidad Aguda , Difracción de Rayos X
12.
Ecotoxicol Environ Saf ; 213: 112043, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33588189

RESUMEN

We describe a green new method for the synthesis of water-soluble photoluminescent carbon dots (CDs) that were functionalized with methimazole (MTZ) and applied to determine Hg2+ based on the fluorescence extinction. Starch obtained from rice was used as a natural source for the production of CDs by hydrothermal treatment. Also, it was proposed a factorial design to optimize the parameters for CD synthesis and the results showed that the luminescence intensity is a function of temperature and not of the heating time in the hydrothermal process. The synthesized CDs were characterized using fluorescence techniques, Fourier transform infrared spectroscopy (FTIR), and UV-Vis spectroscopy. Through transmission electron microscopy (TEM) and dynamic light scattering (DLS), it was found the formation of CDs on a nanometer scale with an average size of 11 nm. The functionalization with MTZ, eliminated all interferences from other metals, indicating a selective response to Hg2+ ions. The method was applied to Hg2+ determination in waters. Under optimal conditions, was obtained a limit of detection of 1.8 × 10-7 mol L-1 with a linear range from 3.3 × 10-7 to 50.0 × 10-6 mol L-1. Therefore, the proposed method can be considered a simple, selective, and precise alternative that minimizes the number of reagents used for Hg2+ determination in natural waters, and can be applied on a large scale in environmental analyzes.


Asunto(s)
Monitoreo del Ambiente/métodos , Mercurio/análisis , Metimazol/química , Puntos Cuánticos/química , Carbono/química , Fluorescencia , Colorantes Fluorescentes/química , Iones/química , Espectrometría de Fluorescencia/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Almidón
13.
Molecules ; 26(3)2021 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-33525729

RESUMEN

In this review from literature appearing over about the past 5 years, we focus on selected selenide reports and related chemistry; we aimed for a digestible, relevant, review intended to be usefully interconnected within the realm of fluorescence and selenium chemistry. Tellurium is mentioned where relevant. Topics include selenium in physics and surfaces, nanoscience, sensing and fluorescence, quantum dots and nanoparticles, Au and oxide nanoparticles quantum dot based, coatings and catalyst poisons, thin film, and aspects of solar energy conversion. Chemosensing is covered, whether small molecule or nanoparticle based, relating to metal ion analytes, H2S, as well as analyte sulfane (biothiols-including glutathione). We cover recent reports of probing and fluorescence when they deal with redox biology aspects. Selenium in therapeutics, medicinal chemistry and skeleton cores is covered. Selenium serves as a constituent for some small molecule sensors and probes. Typically, the selenium is part of the reactive, or active site of the probe; in other cases, it is featured as the analyte, either as a reduced or oxidized form of selenium. Free radicals and ROS are also mentioned; aggregation strategies are treated in some places. Also, the relationship between reduced selenium and oxidized selenium is developed.


Asunto(s)
Colorantes Fluorescentes/química , Selenio/química , Animales , Fluorescencia , Glutatión/química , Humanos , Nanopartículas/química , Puntos Cuánticos/química , Telurio/química
14.
Food Chem ; 351: 129252, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33626469

RESUMEN

Herein, an innovative enzyme free electrochemiluminescence chlorpyrifos sensor was reported based on the incorporation of ternary nanocomposite (ruthenium nanobeads/silver nanoparticles/graphene oxide) on the surface of glassy carbon electrode. The silver nanoparticles as a robust signal enhancing agent were well deposited on the modified graphene oxide/glassy carbon electrode and exhibited supreme electrocatalytic proficiency. Then, Ru(bipy)32+ species in bead-like nanoparticles were uniformly anchored on the surface of the modified electrode with the help of chitosan, as a good crosslinking agent. Boron nitride quantum dots as a new coreactant species showed the excellent proficiency for signal enhancement of the fabricated electrode. The fabricated electrode was successfully used as an ultra-sensitive sensor for trace analysis of chlorpyrifos by ECL technique. The wide linear range and the low detection limit were obtained from 5.0 × 10-15 to 4.2 × 10-9 M and 6.5 × 10-16 M, respectively.


Asunto(s)
Cloropirifos/análisis , Técnicas Electroquímicas/métodos , Mediciones Luminiscentes/métodos , Nanocompuestos/química , Compuestos de Boro/química , Catálisis , Técnicas Electroquímicas/instrumentación , Electrodos , Grafito/química , Límite de Detección , Mediciones Luminiscentes/instrumentación , Nanopartículas del Metal/química , Puntos Cuánticos/química , Rutenio/química , Plata/química
15.
Int J Nanomedicine ; 16: 1313-1330, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33628022

RESUMEN

Nanotechnology has been actively integrated as drug carriers over the last few years to treat various cancers. The main hurdle in the clinical management of cancer is the development of multidrug resistance against chemotherapeutic agents. To overcome the limitations of chemotherapy, the researchers have been developing technological advances for significant progress in the oncotherapy by enabling the delivery of chemotherapeutic agents at increased drug content levels to the targeted spots. Several nano-drug delivery systems designed for tumor-targeting are evaluated in preclinical and clinical trials and showed promising outcomes in cancerous tumors' clinical management. This review describes nanocarrier's importance in managing different types of cancers and emphasizing nanocarriers for drug delivery and cancer nanotherapeutics. It also highlights the recent advances in nanocarriers-based delivery systems, including polymeric nanocarriers, micelles, nanotubes, dendrimers, magnetic nanoparticles, solid lipid nanoparticles, and quantum dots (QDs). The nanocarrier-based composites are discussed in terms of their structure, characteristics, and therapeutic applications in oncology. To conclude, the challenges and future exploration opportunities of nanocarriers in chemotherapeutics are also presented.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Animales , Antineoplásicos/química , Humanos , Lípidos/química , Neoplasias/tratamiento farmacológico , Puntos Cuánticos/química
16.
ACS Appl Mater Interfaces ; 13(7): 7854-7864, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33560115

RESUMEN

Graphene field-effect transistors (GFETs) are suitable building blocks for high-performance electrical biosensors, because graphene inherently exhibits a strong response to charged biomolecules on its surface. However, achieving ultralow limit-of-detection (LoD) is limited by sensor response time and screening effect. Herein, we demonstrate that the detection limit of GFET biosensors can be improved significantly by decorating the uncovered graphene sensor area with carbon dots (CDs). The developed CDs-GFET biosensors used for exosome detection exhibited higher sensitivity, faster response, and three orders of magnitude improvements in the LoD compared with nondecorated GFET biosensors. A LoD down to 100 particles/µL was achieved with CDs-GFET sensor for exosome detection with the capability for further improvements. The results were further supported by atomic force microscopy (AFM) and fluorescent microscopy measurements. The high-performance CDs-GFET biosensors will aid the development of an ultrahigh sensitivity biosensing platform based on graphene for rapid and early diagnosis of diseases.


Asunto(s)
Técnicas Biosensibles , Carbono/química , Exosomas/química , Puntos Cuánticos/química , Transistores Electrónicos , Tamaño de la Partícula , Propiedades de Superficie
17.
J Vis Exp ; (168)2021 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-33616095

RESUMEN

This novel total internal reflection fluorescence microscopy-based assay facilitates the simultaneous measurement of the length of the catalytic cycle for hundreds of individual restriction endonuclease (REase) molecules in one experiment. This assay does not require protein labeling and can be carried out with a single imaging channel. In addition, the results of multiple individual experiments can be pooled to generate well-populated dwell-time distributions. Analysis of the resulting dwell-time distributions can help elucidate the DNA cleavage mechanism by revealing the presence of kinetic steps that cannot be directly observed. Example data collected using this assay with the well-studied REase, EcoRV - a dimeric Type IIP restriction endonuclease that cleaves the palindromic sequence GAT↓ATC (where ↓ is the cut site) - are in agreement with prior studies. These results suggest that there are at least three steps in the pathway to DNA cleavage that is initiated by introducing magnesium after EcoRV binds DNA in its absence, with an average rate of 0.17 s-1 for each step.


Asunto(s)
División del ADN , Enzimas de Restricción del ADN/metabolismo , Imagen Individual de Molécula/métodos , Biotinilación , ADN/metabolismo , Análisis de Datos , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Cinética , Microfluídica , Puntos Cuánticos/química , Especificidad por Sustrato , Propiedades de Superficie , Factores de Tiempo
18.
Food Chem ; 349: 129171, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33582542

RESUMEN

Herein, an innovative ratiometric fluorescence (FL) aptasensor was successfully fabricated for the accurate analysis of zearalenone (ZEN) in corn and barley flour. The ZEN aptamer-modified nitrogen doped graphene quantum dots (NGQDs-apt) and silica sphere-encapsulated cadmium telluride quantum dots (CdTe QDs@SiO2) were directly mixed and applied as ratiometric probes. In the absence of ZEN, mitoxantrone (MTX), which was innovatively introduced as quencher, was captured by NGQDs-apt and its inner filter effect (IFE) on CdTe QDs@SiO2 was inhibited. When ZEN existed, MTX separated from NGQDs-apt and re-dispersed around CdTe QDs@SiO2 owing to the competitive binding of ZEN with its aptamer. As the IFE of free MTX on CdTe QDs@SiO2 recovering, the FL intensity of CdTe QDs@SiO2 was quenched, while the FL intensity of NGQDs-apt was nearly invariant. On this basis, a ratiometric FL aptasensor for ZEN was fabricated, which exhibited outstanding detection performances with a desirable detection limit of 0.32 pg mL-1.


Asunto(s)
Compuestos de Cadmio/química , Productos Agrícolas/química , Grano Comestible/química , Mitoxantrona/química , Puntos Cuánticos/química , Dióxido de Silicio/química , Telurio/química , Zearalenona/análisis , Aptámeros de Nucleótidos , Harina/análisis , Fluorescencia , Grafito , Límite de Detección
19.
Food Chem ; 345: 128812, 2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-33601655

RESUMEN

Due to complex matrixes and specific reagent deficiency, the rapid detection of histamine is still a challenge to date. Based on the high peroxidase-like activity of iron-cobalt co-doped carbon dots, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was established for histamine detection using the mimic enzyme labeled with histamine antibody (His-Ab). Through the competitive binding of the labeled His-Ab to solid-phase and sample antigens, histamine content was detected with a linear range of 2.5-150 µg mL-1. The detection limit based on 3σ/K was 0.50 mg kg-1, which was much lower than those of commercial His-kit and HPLC methods. The ic-ELISA method was applied to histamine detection in fish samples with the recovery of (103.4 ± 0.5)%, which was in accord with those of commercial His-kit and HPLC methods. The results indicated that the established ic-ELISA method was suitable for rapid detection of histamine in fish samples with high accuracy, sensitivity and stability.


Asunto(s)
Peces/metabolismo , Histamina/análisis , Puntos Cuánticos/química , Animales , Anticuerpos/química , Anticuerpos/inmunología , Carbono/química , Cobalto/química , Ensayo de Inmunoadsorción Enzimática , Histamina/inmunología , Hierro/química , Límite de Detección , Reproducibilidad de los Resultados , Alimentos Marinos/análisis
20.
Nat Commun ; 12(1): 812, 2021 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-33547279

RESUMEN

Carbon dots (CDs) are photoluminescent nanomaterials with wide-ranging applications. Despite their photoactivity, it remains unknown whether CDs degrade under illumination and whether such photodegradation poses any cytotoxic effects. Here, we show laboratory-synthesized CDs irradiated with light degrade into molecules that are toxic to both normal (HEK-293) and cancerous (HeLa and HepG2) human cells. Eight days of irradiation photolyzes 28.6-59.8% of the CDs to <3 kilo Dalton molecules, 1431 of which are detected by high-throughput, non-target high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Molecular network and community analysis further reveal 499 cytotoxicity-related molecules, 212 of which contain polyethylene glycol, glucose, or benzene-related structures. Photo-induced production of hydroxyl and alkyl radicals play important roles in CD degradation as affected by temperature, pH, light intensity and wavelength. Commercial CDs show similar photodegraded products and cytotoxicity profiles, demonstrating that photodegradation-induced cytotoxicity is likely common to CDs regardless of their chemical composition. Our results highlight the importance of light in cytocompatibility studies of CDs.


Asunto(s)
Carbono/toxicidad , Citotoxinas/toxicidad , Puntos Cuánticos/toxicidad , Derivados del Benceno/química , Derivados del Benceno/toxicidad , Carbono/química , Carbono/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Citotoxinas/química , Glucosa/química , Glucosa/toxicidad , Células HEK293 , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Radical Hidroxilo/química , Radical Hidroxilo/toxicidad , Cinética , Luz , Fotólisis , Polietilenglicoles/química , Polietilenglicoles/toxicidad , Puntos Cuánticos/química , Puntos Cuánticos/efectos de la radiación , Temperatura
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