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1.
Top Curr Chem (Cham) ; 378(2): 28, 2020 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-32125549

RESUMEN

Titanium dioxide (TiO2) is increasingly being used in biosensing applications. Herein, we review the most recent developments in photoelectrochemical (PEC) and electrochemiluminescent (ECL) biosensing based on TiO2 nanomaterials, as well as the mechanisms that lead to the improved performance of biosensors that incorporate these nanomaterials. The merits of TiO2-based ECL and PEC biosensing strategies are summarized by highlighting some illustrative examples that have been reported within the last 5 years. The future prospects for and challenges in this field are also discussed.


Asunto(s)
Técnicas Biosensibles/métodos , Nanoestructuras/química , Titanio/química , Toxina del Cólera/análisis , ADN/análisis , Técnicas Electroquímicas , Mediciones Luminiscentes , Rayos Ultravioleta
3.
J Agric Food Chem ; 68(8): 2554-2561, 2020 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-32027503

RESUMEN

Excessive use of antibiotics in aquatic products is a serious problem for food safety and human health, and on-site detection of antibiotics is highly demanded. Herein, we proposed multivalence aptamer probes, allowing sensitive, label-free, and homogeneous detection of antibiotics in different aquatic products. Compared to commonly used aptamers, multivalence aptamer probes can provide multiple binding sites and a higher affinity for target molecules, and the iterative binding on different binding sites contributes to an amplified recognition effect, sharply increasing the response and sensitivity of aptamer probes. The 2-valence aptamer probes conferred a limit of detection of 0.097 nM for kanamycin detection, where it is estimated that their sensitivity is enhanced 12 times compared to 1-valence aptamer probes. Meanwhile, multivalence aptamer probes allowed us to specifically identify kanamycin among other antibiotics. It could detect kanamycin residual in aquatic products including river eel and puffer fish, as well as tap water with high precision. A multivalence design strategy of aptamer probes would significantly improve the detection performance of aptamers, facilitating the translation of aptamer for food safety control.


Asunto(s)
Antibacterianos/análisis , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Residuos de Medicamentos/análisis , Alimentos Marinos/análisis , Animales , Aptámeros de Nucleótidos/síntesis química , Acuicultura , Técnicas Biosensibles/instrumentación , Peces/crecimiento & desarrollo , Contaminación de Alimentos/análisis , Agua Dulce/análisis , Kanamicina/análisis , Límite de Detección , Contaminantes Químicos del Agua/análisis
4.
Top Curr Chem (Cham) ; 378(1): 18, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32009187

RESUMEN

DNA molecules with superior flexibility, affinity and programmability have garnered considerable attention for the controllable assembly of nanoparticles (NPs). By controlling the density, length and sequences of DNA on NPs, the configuration of NP assemblies can be rationally designed. The specific recognition of DNA enables changes to be made to the spatial structures of NP assemblies, resulting in differences in tailorable optical signals. Comprehensive information on the fabrication of DNA-driven NP assemblies would be beneficial for their application in biosensing and bioimaging. This review analyzes the progress of DNA-driven NP assemblies, and discusses the tunable configurations determined by the structural parameters of DNA skeletons. The collective optical properties, such as chirality, fluorescence and surface enhanced Raman resonance (SERS), etc., of DNA-driven NP assemblies are explored, and engineered tailorable optical properties of these spatial structures are achieved. We discuss the development of DNA-directed NP assemblies for the quantification of DNA, toxins, and heavy metal ions, and demonstrate their potential application in the biosensing and bioimaging of tumor markers, RNA, living metal ions and phototherapeutics. We hihghlight possible challenges in the development of DNA-driven NP assemblies, and further direct potential prospects in the practical applications of macroscopical materials and photonic devices.


Asunto(s)
Técnicas Biosensibles/métodos , ADN/química , Nanopartículas/química , Imagen Óptica/métodos , Biomarcadores de Tumor/análisis , Grafito/química , Humanos , Metales/química , Espectrometría Raman
5.
Top Curr Chem (Cham) ; 378(1): 20, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32016608

RESUMEN

Nucleic acids are considered not only extraordinary carriers of genetic information but also are perceived as the perfect elemental materials of molecular recognition and signal transduction/amplification for assembling programmable artificial reaction networks or circuits, which are similar to conventional electronic logic devices. Among these sophisticated DNA-based reaction networks, catalytic hairpin assembly (CHA), hybridization chain reaction (HCR), and DNAzyme represent the typical nonenzymatic amplification methods with high robustness and efficiency. Furthermore, their extensive hierarchically cascade integration into multi-layered autonomous DNA circuits establishes novel paradigms for constructing more different catalytic DNA nanostructures and for regenerating or replicating diverse molecular components with specific functions. Various DNA and inorganic nanoscaffolds have been used to realize the surface-confined DNA reaction networks with significant biomolecular sensing and signal-regulating functions in living cells. Especially, the specific aptamers and metal-ion-bridged duplex DNA nanostructures could extend their paradigms for detecting small molecules and proteins in even living entities. Herein, the varied enzyme-free DNA circuits are introduced in general with an extensive explanation of their underlying molecular reaction mechanisms. Challenges and outlook of the autonomous enzyme-free DNA circuits will also be discussed at the end of this chapter.


Asunto(s)
Técnicas Biosensibles/métodos , ADN/química , ADN/metabolismo , ADN Catalítico/química , ADN Catalítico/metabolismo , Entropía , Transferencia Resonante de Energía de Fluorescencia , Humanos , Microscopía Fluorescente , Nanoestructuras/química , Hibridación de Ácido Nucleico
6.
Top Curr Chem (Cham) ; 378(2): 21, 2020 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-32030541

RESUMEN

DNA nanostructures hold great promise for various applications due to their remarkable properties, including programmable assembly, nanometric positional precision, and dynamic structural control. The past few decades have seen the development of various kinds of DNA nanostructures that can be employed as useful tools in fields such as chemistry, materials, biology, and medicine. Aptamers are short single-stranded nucleic acids that bind to specific targets with excellent selectivity and high affinity and play critical roles in molecular recognition. Recently, many attempts have been made to integrate aptamers with DNA nanostructures for a range of biological applications. This review starts with an introduction to the features of aptamer-functionalized DNA nanostructures. The discussion then focuses on recent progress (particularly during the last five years) in the applications of these nanostructures in areas such as biosensing, bioimaging, cancer therapy, and biophysics. Finally, challenges involved in the practical application of aptamer-functionalized DNA nanostructures are discussed, and perspectives on future directions for research into and applications of aptamer-functionalized DNA nanostructures are provided.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , ADN/química , Nanoestructuras/química , Técnicas Electroquímicas , Terapia Genética , Humanos , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Imagen Óptica/métodos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/uso terapéutico
7.
Science ; 367(6478): 627-628, 2020 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-32029615
8.
Chem Commun (Camb) ; 56(16): 2483-2486, 2020 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-32002523

RESUMEN

Through a rational construction of an RNA toehold switch sensor, the glucometer-based detection of nucleic acids was innovatively simplified into a completely homogeneous and label-free process. Compared with traditional strategies that rely on multiple operations such as chemical conjugation and bead separation, this new strategy is more robust, user-friendly, reagent-saving, and reproducible, and can be universally adapted for use on extensive target species, e.g. herein, the real-world pathogen genes.


Asunto(s)
Técnicas Biosensibles , ADN/análisis , ARN/análisis , Técnicas de Amplificación de Ácido Nucleico
9.
Chem Commun (Camb) ; 56(20): 2971-2974, 2020 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-32073050

RESUMEN

We demonstrate for the first time that host-guest recognition coupled with triple signal amplification endows an electrochemiluminescent (ECL) biosensor with enhanced sensitivity for uracil DNA glycosylase (UDG) assay. This biosensor exhibits good selectivity and extremely high sensitivity, and it can be used to screen UDG inhibitors and measure the cellular UDG activity as well.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Luminiscencia , Uracil-ADN Glicosidasa/análisis , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Células HeLa , Humanos , Uracil-ADN Glicosidasa/antagonistas & inhibidores , Uracil-ADN Glicosidasa/metabolismo
10.
J Agric Food Chem ; 68(9): 2826-2831, 2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32045247

RESUMEN

In this work, we have developed an all-in-one aptasensor based on an enzyme-driven three-dimensional DNA walker for antibiotic detection. To overcome the drawback of time-consuming methods, high-density substrate strands were anchored on the walking interface that accelerated the signal amplification efficiency. Such an all-in-one design integrated the functionality of target recognition, signal amplification, as well as signal output into a single probe. Upon addition of kanamycin, the activated walking strand moved along the track by the stepwise cleavage of a nicking enzyme, which resulted in the enhancement of the fluorescence intensity of the solution. Under the optimized conditions, the detection process was accomplished in 40 min with a low detection limit of 1.23 pM. This aptasensor was also applied in spiked milk samples with satisfactory recoveries of 97.76% to 105.33%, demonstrating an excellent stability and accuracy. Therefore, this all-in-one aptasensor shows great potential for applications in food safety.


Asunto(s)
Antibacterianos/análisis , Técnicas Biosensibles/métodos , Animales , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/instrumentación , Bovinos , Contaminación de Alimentos/análisis , Oro/química , Kanamicina/análisis , Límite de Detección , Leche/química
11.
Anal Bioanal Chem ; 412(8): 1893-1899, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32016568

RESUMEN

Superoxide dismutase (SOD), also known as liver protein, is a substance widely distributed in various biological cells. It has the function of catalyzing the disproportionation reaction of superoxide free radicals. SOD can form an antioxidant chain together with peroxidase, catalase, and other substances in the body of organisms, and thus, is one of the indispensable important substances in the body of organisms. In this work, we provided a simple and fast visual electrochemiluminescence (ECL) sensor for SOD detection. CuInZnS quantum dots (QDs) worked as the ECL luminophore with hydrogen peroxide as co-reactant. In the sensing process, SOD and CuInZnS QDs on a glassy carbon electrode (GCE) competed with each other for hydrogen peroxide to produce superoxide during electrochemical luminescence, thus quenching the ECL signal of CuInZnS QDs. The proposed sensor can quantify SOD with a limit of detection (LOD) of 0.03 µg/mL. In addition, the change in the CuInZnS QDs ECL signal was easily observed with a smartphone camera. The results indicated that this sensor could effectively work in the detection of SOD in human blood. Graphical abstract.


Asunto(s)
Cobre/química , Técnicas Electroquímicas/métodos , Indio/química , Luminiscencia , Puntos Cuánticos/química , Sulfuros/química , Superóxido Dismutasa/análisis , Compuestos de Zinc/química , Técnicas Biosensibles , Límite de Detección , Reproducibilidad de los Resultados
12.
Chem Commun (Camb) ; 56(17): 2658-2661, 2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-32022034

RESUMEN

A DNAzyme-powered micromachine with anti-interfering properties and displaying resistance to being inhibited by biological matrices was built. This micromachine was able to respond to a specific target in high-concentration serum or whole blood.


Asunto(s)
Técnicas Biosensibles/instrumentación , ADN Catalítico/metabolismo , Sondas de ADN/química , ADN Catalítico/antagonistas & inhibidores
13.
Anal Bioanal Chem ; 412(8): 1933-1946, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32076788

RESUMEN

Biogenic amine biosensors, based on screen-printed carbon electrodes (SPCE) modified with Prussian blue (PB) and indium tin oxide nanoparticles (ITONP), are reported. PB/ITONP-modified SPCE was further modified with diamine oxidase (DAO) or monoamine oxidase (MAO) enzymes to construct the biosensors. The morphology of the modified electrodes was studied by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and atomic force microscopy (AFM). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to enlighten the electrochemical properties of the modified electrodes at each step of biosensor fabrication. Electrode surface composition and experimental conditions were optimized and analytical performance characteristics of the biosensors were studied. Several biogenic amines were tested and both biosensors responded to histamine, putrescine and cadaverine. DAO/ITONP/PB/SPCE biosensor exhibited the highest response to histamine 6.0 × 10-6-6.9 × 10-4 M with a sensitivity of 1.84 µA mM-1. On the other hand, the highest sensitivity was obtained for cadaverine with the MAO/ITONP/PB/SPCE biosensor. The analytical utility of the presented biosensors were illustrated by the determination of cadaverine and histamine in cheese sample.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/química , Aminas Biogénicas/análisis , Técnicas Electroquímicas/instrumentación , Electrodos , Ferrocianuros/química , Nanopartículas del Metal/química , Monoaminooxidasa/química , Compuestos de Estaño/química , Técnicas Biosensibles
14.
Anal Bioanal Chem ; 412(3): 611-620, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31900539

RESUMEN

Infections caused by foodborne microorganisms are a great threat to the global environment and public healthcare today. Thus, rapid, portable and sensitive assays that can realize the identification of foodborne bacteria are highly desired. In this study, a smart fluorescent and colorimetric dual-readout sensing system has been established for simple and rapid E. coli determination by utilizing the Cu2+-triggered oxidation of o-phenylenediamine (OPD). Initially, Cu2+ can oxidize OPD to OPDox, resulting in an orange-yellow fluorescence and visible pale-yellow color. However, E. coli can effectively reduce Cu2+ into Cu+, inhibiting the Cu2+-triggered oxidation of OPD to OPDox. Consequently, the introduction of E. coli can turn off both the fluorescence and the UV-vis absorbance signals of the OPD-Cu2+ system, illustrating an original mechanism for fluorescent and colorimetric dual-channel detection of E. coli. Moreover, a filter paper-based visual sensor was built and coupled with OPD-Cu2+ solution under the assistance of a UV lamp. The as-prepared sensor can detect E. coli quantitatively with the help of a typical smartphone color-scanning application (APP). Thus, this study offers a valid dual-mode assay for sensitive and on-site visible detection of E. coli, guaranteeing the reliability of the results and is more attractive for practical use. Graphical Abstract Schematic illustration of the smartphone-integrated sensing system for fluorescent and colorimetric dual-channel detection of E. coli based on the Cu2+-OPD system.


Asunto(s)
Bacterias/aislamiento & purificación , Colorimetría/métodos , Colorantes Fluorescentes/química , Microbiología de Alimentos , Papel , Teléfono Inteligente , Espectrometría de Fluorescencia/métodos , Integración de Sistemas , Bacterias/patogenicidad , Técnicas Biosensibles , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta/métodos
15.
Anal Bioanal Chem ; 412(1): 55-72, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31912182

RESUMEN

During recent decades, nucleic acid aptamers have emerged as powerful biological recognition elements for electrochemical affinity biosensors. These bioreceptors emulate or improve on antibody-based biosensors because of their excellent characteristics as bioreceptors, including limitless selection capacity for a large variety of analytes, easy and cost-effective production, high stability and reproducibility, simple chemical modification, stable and oriented immobilization on electrode surfaces, enhanced target affinity and selectivity, and possibility to design them in target-sensitive 3D folded structures. This review provides an overview of the state of the art of electrochemical aptasensor technology, focusing on novel aptamer-based electroanalytical assay configurations and providing examples to illustrate the different possibilities. Future prospects for this technology are also discussed. Graphical abstract.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnicas Biosensibles , Técnicas Electroquímicas/instrumentación , Biomarcadores/análisis , Contaminantes Ambientales/análisis , Inocuidad de los Alimentos , Humanos , Medidas de Seguridad
16.
Chem Commun (Camb) ; 56(9): 1413-1416, 2020 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-31912820

RESUMEN

A novel ratiometric surface-enhanced Raman scattering (SERS) biosensor was constructed based on stimuli-responsive DNA functionalized metal organic frameworks (MOFs) for detection of adenosine triphosphate (ATP). As a result, the detection range of ATP was 1 nM to 200 nM with a detection limit of 0.4 nM. The ratiometric SERS biosensor strategy offers a lower detection limit and exhibits a more enhanced performance than the typical SERS detection based on single signal response, which may have potential for detection of other biomolecules or metal ions.


Asunto(s)
Adenosina Trifosfato/química , Técnicas Biosensibles , ADN/química , Estructuras Metalorgánicas/química , Espectrometría Raman , Propiedades de Superficie
18.
Nat Commun ; 11(1): 534, 2020 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-31988280

RESUMEN

A disturbance of reactive oxygen species (ROS) homeostasis may cause the pathogenesis of many diseases. Inspired by natural photosynthesis, this work proposes a photo-driven H2-evolving liposomal nanoplatform (Lip NP) that comprises an upconversion nanoparticle (UCNP) that is conjugated with gold nanoparticles (AuNPs) via a ROS-responsive linker, which is encapsulated inside the liposomal system in which the lipid bilayer embeds chlorophyll a (Chla). The UCNP functions as a transducer, converting NIR light into upconversion luminescence for simultaneous imaging and therapy in situ. Functioning as light-harvesting antennas, AuNPs are used to detect the local concentration of ROS for FRET biosensing, while the Chla activates the photosynthesis of H2 gas to scavenge local excess ROS. The results thus obtained indicate the potential of using the Lip NPs in the analysis of biological tissues, restoring their ROS homeostasis, possibly preventing the initiation and progression of diseases.


Asunto(s)
Clorofila/metabolismo , Hidrógeno/metabolismo , Liposomas/metabolismo , Nanopartículas del Metal/química , Fotosíntesis , Especies Reactivas de Oxígeno/metabolismo , Técnicas Biosensibles , Oro , Nanoestructuras
19.
Nat Commun ; 11(1): 535, 2020 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-31988308

RESUMEN

To date, numerous biosensing platforms have been developed for assessing drug-induced cardiac toxicity by measuring the change in contractile force of cardiomyocytes. However, these low sensitivity, low-throughput, and time-consuming processes are severely limited in their real-time applications. Here, we propose a cantilever device integrated with a polydimethylsiloxane (PDMS)-encapsulated crack sensor to measure cardiac contractility. The crack sensor is chemically bonded to a PDMS thin layer that allows it to be operated very stably in culture media. The reliability of the proposed crack sensor has been improved dramatically compared to no encapsulation layer. The highly sensitive crack sensor continuously measures the cardiac contractility without changing its gauge factor for up to 26 days (>5 million heartbeats), while changes in contractile force induced by drugs are monitored using the crack sensor-integrated cantilever. Finally, experimental results are compared with those obtained via conventional optical methods to verify the feasibility of building a contraction-based drug-toxicity testing system.


Asunto(s)
Técnicas Biosensibles , Dimetilpolisiloxanos/química , Contracción Miocárdica/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Animales , Evaluación Preclínica de Medicamentos/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Miocitos Cardíacos/fisiología , Quinidina/toxicidad , Ratas Sprague-Dawley , Verapamilo/toxicidad
20.
Anal Bioanal Chem ; 412(3): 601-609, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31897558

RESUMEN

Numerous studies have shown that exosomes are closely related to the pathogenesis of various diseases, especially cancers. Therefore, a rapid and sensitive method for exosome detection will be of great importance for the diagnosis and prognosis of diseases. We report here a method for exosome detection based on the CD63 aptamer and clustered regular interspaced short palindromic repeats (CRISPR)/Cas12a system. This method consists mainly of exosomal membrane protein recognition based on the CD63 aptamer and signal amplification based on CRISPR/Cas12a. The CD63 aptamer, as an easily adaptable nucleic acid strand, is responsible for the conversion of the amounts of exosomes into nucleic acid detection, whereas CRISPR/Cas12a is responsible for highly specific nucleic acid signal amplification. The detection range of the method was determined as 3 × 103-6 × 107 particles per microliter. Additionally, we successfully applied this method to detect exosomes in clinical samples from both healthy individuals and patients with lung cancer, and the results were highly consistent with those obtained by nanoparticle tracking analysis. In general, this method provides a highly sensitive and specific method for the detection of exosomes and offers an avenue toward future exosome-based diagnosis of diseases.


Asunto(s)
Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Exosomas/química , Tetraspanina 30/análisis , Células A549 , Sistemas CRISPR-Cas , Exosomas/patología , Humanos , Neoplasias Pulmonares/patología , Técnicas de Amplificación de Ácido Nucleico/métodos
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