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1.
Environ Pollut ; 266(Pt 3): 115389, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32805682

RESUMO

The increased occurrence of Mercury (Hg II) contaminant has caused environmental and health concerns worldwide. Removal of Hg(II) from water is of significant interest, in particular if these can be coupled in a manner of detection. Here, a novel activated carbon (AC) adsorbent and a fast detection device to form a closed-cycle strategy was developed. The synthesis of conjugates of streptavidin-biotinylated DNA probes modified gold nanoparticle was used with lateral flow biosensors for Hg(II) detection. A quantification was completed via a self-developed smartphone app and its limit of detection was 2.53 nM. Moreover, AC was activated with a new activating agent of diammonium hydrogen phosphate. The adsorbent was characterized and determined to have an amorphous microporous structure with a high surface area (1076.5 m2 g-1) and demonstrated excellent removal efficiency (99.99%) and adsorption capacity (∼100 mg g-1) for Hg(II). The kinetics of the pseudo-second-order model and the mechanisms of electrostatic adsorption, ion exchange, and complex reactions are provided. The proposed closed-cycle strategy can be useful for early, fast, and mobile detection of Hg (II) pollution, followed by its effective removal during water treatment.


Assuntos
Técnicas Biossensoriais , Mercúrio/análise , Nanopartículas Metálicas , Smartphone , Poluentes Químicos da Água/análise , Adsorção , Sondas de DNA , Ouro , Concentração de Íons de Hidrogênio , Cinética , Estreptavidina
2.
Emerg Microbes Infect ; 9(1): 1175-1179, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: covidwho-361278

RESUMO

Different primers/probes sets have been developed all over the world for the nucleic acid detection of SARS-CoV-2 by quantitative real time polymerase chain reaction (qRT-PCR) as a standard method. In our recent study, we explored the feasibility of droplet digital PCR (ddPCR) for clinical SARS-CoV-2 nucleic acid detection compared with qRT-PCR using the same primer/probe sets issued by Chinese Center for Disease Control and Prevention (CDC) targeting viral ORF1ab or N gene, which showed that ddPCR could largely minimize the false negatives reports resulted by qRT-PCR [Suo T, Liu X, Feng J, et al. ddPCR: a more sensitive and accurate tool for SARS-CoV-2 detection in low viral load specimens. medRxiv [Internet]. 2020;2020.02.29.20029439. Available from: https://medrxiv.org/content/early/2020/03/06/2020.02.29.20029439.abstract]. Here, we further stringently compared the performance of qRT-PCR and ddPCR for 8 primer/probe sets with the same clinical samples and conditions. Results showed that none of 8 primer/probe sets used in qRT-PCR could significantly distinguish true negatives and positives with low viral load (10-4 dilution). Moreover, false positive reports of qRT-PCR with UCDC-N1, N2 and CCDC-N primers/probes sets were observed. In contrast, ddPCR showed significantly better performance in general for low viral load samples compared to qRT-PCR. Remarkably, the background readouts of ddPCR are relatively lower, which could efficiently reduce the production of false positive reports.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Reação em Cadeia da Polimerase Multiplex , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase em Tempo Real , Primers do DNA , Sondas de DNA , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Pandemias , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Sensibilidade e Especificidade , Carga Viral
3.
Anal Chem ; 92(14): 9699-9705, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32441935

RESUMO

A novel coronavirus (SARS-CoV-2) was recently identified in patients with acute respiratory disease and spread quickly worldwide. A specific and rapid diagnostic method is important for early identification. The reverse-transcription recombinase-aided amplification (RT-RAA) assay is a rapid detection method for several pathogens. Assays were performed within 5-15 min as a one-step single tube reaction at 39 °C. In this study, we established two RT-RAA assays for the S and orf1ab gene of SARS-CoV-2 using clinical specimens for validation. The analytical sensitivity of the RT-RAA assay was 10 copies for the S and one copy for the orf1ab gene per reaction. Cross-reactions were not observed with any of the other respiratory pathogens. A 100% agreement between the RT-RAA and real-time PCR assays was accomplished after testing 120 respiratory specimens. These results demonstrate that the proposed RT-RAA assay will be beneficial as it is a faster, more sensitive, and more specific tool for the detection of SARS-CoV-2.


Assuntos
Betacoronavirus/química , Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase/métodos , Bactérias/química , Bactérias/genética , Reações Cruzadas , Sondas de DNA , Genes Virais , Humanos , Pandemias , Plasmídeos , Infecções Respiratórias/microbiologia , Infecções Respiratórias/virologia , Sensibilidade e Especificidade , Proteínas Virais/genética , Vírus/química , Vírus/genética
4.
Clin Chem ; 66(8): 1047-1054, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32384153

RESUMO

BACKGROUND: The current outbreak of SARS-CoV-2 has spread to almost every country with more than 5 million confirmed cases and over 300,000 deaths as of May 26, 2020. Rapid first-line testing protocols are needed for outbreak control and surveillance. METHODS: We used computational and manual designs to generate a suitable set of reverse transcription recombinase polymerase amplification (RT-RPA) primer and exonuclease probe, internally quenched (exo-IQ), sequences targeting the SARS-CoV-2 N gene. RT-RPA sensitivity was determined by amplification of in vitro transcribed RNA standards. Assay selectivity was demonstrated with a selectivity panel of 32 nucleic acid samples derived from common respiratory viruses. To validate the assay against full-length SARS-CoV-2 RNA, total viral RNA derived from cell culture supernatant and 19 nasopharyngeal swab samples (8 positive and 11 negative for SARS-CoV-2) were screened. All results were compared to established RT-qPCR assays. RESULTS: The 95% detection probability of the RT-RPA assay was determined to be 7.74 (95% CI: 2.87-27.39) RNA copies per reaction. The assay showed no cross-reactivity to any other screened coronaviruses or respiratory viruses of clinical significance. The developed RT-RPA assay produced 100% diagnostic sensitivity and specificity when compared to RT-qPCR (n = 20). CONCLUSIONS: With a run time of 15 to 20 minutes and first results being available in under 7 minutes for high RNA concentrations, the reported assay constitutes one of the fastest nucleic acid based detection methods for SARS-CoV-2 to date and may provide a simple-to-use alternative to RT-qPCR for first-line screening at the point of need.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Técnicas de Amplificação de Ácido Nucleico/métodos , Pneumonia Viral/diagnóstico , RNA Viral/metabolismo , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/virologia , Sondas de DNA/química , Sondas de DNA/metabolismo , Exonucleases/metabolismo , Humanos , Pandemias , Pneumonia Viral/virologia , Testes Imediatos , Reação em Cadeia da Polimerase em Tempo Real , Sensibilidade e Especificidade
5.
Emerg Infect Dis ; 26(8): 1944-1946, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32433015
6.
Emerg Microbes Infect ; 9(1): 1175-1179, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32448084

RESUMO

Different primers/probes sets have been developed all over the world for the nucleic acid detection of SARS-CoV-2 by quantitative real time polymerase chain reaction (qRT-PCR) as a standard method. In our recent study, we explored the feasibility of droplet digital PCR (ddPCR) for clinical SARS-CoV-2 nucleic acid detection compared with qRT-PCR using the same primer/probe sets issued by Chinese Center for Disease Control and Prevention (CDC) targeting viral ORF1ab or N gene, which showed that ddPCR could largely minimize the false negatives reports resulted by qRT-PCR [Suo T, Liu X, Feng J, et al. ddPCR: a more sensitive and accurate tool for SARS-CoV-2 detection in low viral load specimens. medRxiv [Internet]. 2020;2020.02.29.20029439. Available from: https://medrxiv.org/content/early/2020/03/06/2020.02.29.20029439.abstract]. Here, we further stringently compared the performance of qRT-PCR and ddPCR for 8 primer/probe sets with the same clinical samples and conditions. Results showed that none of 8 primer/probe sets used in qRT-PCR could significantly distinguish true negatives and positives with low viral load (10-4 dilution). Moreover, false positive reports of qRT-PCR with UCDC-N1, N2 and CCDC-N primers/probes sets were observed. In contrast, ddPCR showed significantly better performance in general for low viral load samples compared to qRT-PCR. Remarkably, the background readouts of ddPCR are relatively lower, which could efficiently reduce the production of false positive reports.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Reação em Cadeia da Polimerase Multiplex , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Reação em Cadeia da Polimerase em Tempo Real , Primers do DNA , Sondas de DNA , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Pandemias , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/normas , Sensibilidade e Especificidade , Carga Viral
7.
J Chromatogr A ; 1624: 461148, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32376029

RESUMO

The variation patterns of transcription factors (TFs) provide direct information for the states of cell populations, which is of significance for biomedical research and clinical diagnostics. Herein, we show that through multi-channeled isothermal amplification, it is feasible to connect DNA-based signal transduction with chromatography for multiplexed detection of TFs. The described system is referred to as "PAC" which includes three major steps: (i) Protection, which uses DNA-modified magnetic beads to capture TFs and converts the capturing event into triggering signal; (ii) Amplification, which receives the triggering signal and generate DNA reporters through multi-channeled extension and nicking of oligonucleotides; and (iii) Chromatography, which separates and detects the DNA reporters in liquid chromatography. The quantitative detection of five essential TFs includes p50, p53, AP-1, MITF, and c-Myc is realized in a multiplexed manner, with the lowest detection limit of 0.5 pM. PAC can also provide effective means to measure the above five TFs in real samples, including cultured cells, xenograft tumors, and blood-based liquid biopsy. This study not only established a solution for multiplexed measurement of TFs for molecular diagnostics, but also paved avenue for bridging the gap between DNA nanotechnology and chromatography.


Assuntos
Cromatografia Líquida , Técnicas de Amplificação de Ácido Nucleico , Fatores de Transcrição/análise , Animais , Células Cultivadas , DNA/química , Sondas de DNA , Humanos , Limite de Detecção , Biópsia Líquida , Camundongos , Nanoestruturas , Nanotecnologia , Oligonucleotídeos , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Mol Cell Probes ; 53: 101599, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32425334

RESUMO

•Most of the COVID-19 cases in Nepal are in the Southern districts of Nepal bordering India with travel histories to India.•Very few positive cases of COVID-19 are detected in Nepal which could either be due to early national lockdown.•Low PCR positivity rates could also be due to inefficiency of the PCR methods.•Whole genomes of 93 clinical samples from COVID-19 patients were analyzed to find the primer and probe binding sites.•Mutations in probe binding sites were found which could impact PCR efficiency resulting in false negative results.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Genoma Viral , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Betacoronavirus/classificação , Betacoronavirus/patogenicidade , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Sondas de DNA/normas , Reações Falso-Negativas , Humanos , Índia/epidemiologia , Mutação , Nepal/epidemiologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Kit de Reagentes para Diagnóstico/normas , Índice de Gravidade de Doença , Migrantes
9.
Proc Natl Acad Sci U S A ; 117(16): 8719-8726, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32241887

RESUMO

Rapid methods for diagnosis of bacterial infections are urgently needed to reduce inappropriate use of antibiotics, which contributes to antimicrobial resistance. In many rapid diagnostic methods, DNA oligonucleotide probes, attached to a surface, bind to specific nucleotide sequences in the DNA of a target pathogen. Typically, each probe binds to a single target sequence; i.e., target-probe binding is monovalent. Here we show using computer simulations that the detection sensitivity and specificity can be improved by designing probes that bind multivalently to the entire length of the pathogen genomic DNA, such that a given probe binds to multiple sites along the target DNA. Our results suggest that multivalent targeting of long pieces of genomic DNA can allow highly sensitive and selective binding of the target DNA, even if competing DNA in the sample also contains binding sites for the same probe sequences. Our results are robust to mild fragmentation of the bacterial genome. Our conclusions may also be relevant for DNA detection in other fields, such as disease diagnostics more broadly, environmental management, and food safety.


Assuntos
Desenho Assistido por Computador , Sondas de DNA , DNA Bacteriano/isolamento & purificação , Genoma Bacteriano , Sondas de Oligonucleotídeos , Biologia Computacional/métodos , Simulação por Computador , DNA Bacteriano/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos
10.
Food Chem ; 322: 126758, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283372

RESUMO

A paper-based DNA biosensor was developed for food authenticity testing using dairy products as a model. DNA from milk-based samples was isolated, and species-specific DNA sequences were amplified and identified by the biosensor using specific DNA probes. The properties of gold nanoparticles were exploited for visual detection. The biosensor was applied for detection of three species, namely cow, sheep and goat, while as low as 1.6 fmol for cow and goat, and 3.1 fmol for sheep PCR product were detected. Moreover, adulteration down to 0.01% could be detected, based on binary mixtures of cows', ewes' and goats' milk yogurt, containing 0.01 to 5% of cows' yogurt in ewes' and goats' yogurts, respectively. The proposed paper-based DNA biosensor offered 10 times higher detectability than other methods, good specificity and reproducibility, and could be applied easily for the detection of other adulterated food products, such as meat, olive oil and legumes.


Assuntos
Técnicas Biossensoriais/métodos , DNA/análise , Contaminação de Alimentos/análise , Leite/química , Papel , Animais , Bovinos , DNA/metabolismo , Sondas de DNA/metabolismo , Feminino , Cabras/genética , Ouro/química , Nanopartículas Metálicas/química , Leite/metabolismo , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Ovinos/genética , Iogurte/análise
11.
Nat Commun ; 11(1): 1543, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32210235

RESUMO

Field-effect transistor (FET)-based biosensors allow label-free detection of biomolecules by measuring their intrinsic charges. The detection limit of these sensors is determined by the Debye screening of the charges from counter ions in solutions. Here, we use FETs with a deformed monolayer graphene channel for the detection of nucleic acids. These devices with even millimeter scale channels show an ultra-high sensitivity detection in buffer and human serum sample down to 600 zM and 20 aM, respectively, which are ∼18 and ∼600 nucleic acid molecules. Computational simulations reveal that the nanoscale deformations can form 'electrical hot spots' in the sensing channel which reduce the charge screening at the concave regions. Moreover, the deformed graphene could exhibit a band-gap, allowing an exponential change in the source-drain current from small numbers of charges. Collectively, these phenomena allow for ultrasensitive electronic biomolecular detection in millimeter scale structures.


Assuntos
Técnicas Biossensoriais/instrumentação , Sondas de DNA/análise , DNA de Cadeia Simples/análise , Grafite/química , MicroRNAs/análise , Sondas de DNA/química , DNA de Cadeia Simples/química , Estudos de Viabilidade , Humanos , Íons , Limite de Detecção , MicroRNAs/química , Simulação de Dinâmica Molecular , Sensibilidade e Especificidade , Transistores Eletrônicos
12.
Chem Commun (Camb) ; 56(17): 2658-2661, 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32022034

RESUMO

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.


Assuntos
Técnicas Biossensoriais/instrumentação , DNA Catalítico/metabolismo , Sondas de DNA/química , DNA Catalítico/antagonistas & inibidores
13.
Chem Commun (Camb) ; 56(19): 2901-2904, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32037435

RESUMO

The enzymatic-assisted signal amplification of DNA sensors is rarely applied in living cells due to the difficulties in protein delivery. In this study, we have proposed a biomineralization-based DNA nanoprobe to transport nucleases and DNA sensors for enzyme-assisted imaging of microRNA in living cells.


Assuntos
Biomineralização , Sondas de DNA/química , DNA/metabolismo , Exodesoxirribonucleases/metabolismo , Nanopartículas/química , Humanos , Estruturas Metalorgânicas/química , MicroRNAs/metabolismo
14.
Chem Commun (Camb) ; 56(11): 1681-1684, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31939961

RESUMO

A functionalized dumbbell probe (FDP) based amplification method, termed as a cascading exponential amplification DNA machine (CEA-DNA machine), has been developed to autonomously accumulate single G-quadruplexes (SGQs) and twin-G-quadruplexes (TGQs) for robust fluorescence signal-on probing of miRNA-21.


Assuntos
DNA/química , MicroRNAs/sangue , Técnicas de Amplificação de Ácido Nucleico/métodos , Espectrometria de Fluorescência/métodos , Benzotiazóis/química , Técnicas Biossensoriais/métodos , Linhagem Celular Tumoral , DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , Corantes Fluorescentes/química , Quadruplex G , Humanos , Sequências Repetidas Invertidas , Limite de Detecção , MicroRNAs/genética , Hibridização de Ácido Nucleico
16.
Chem Commun (Camb) ; 56(10): 1501-1504, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31915759

RESUMO

A new DNA nanoprobe based on a Y-shape and pyrene-modified DNA self-assembly is developed to sensitively and specifically detect microRNA through a pyrene excimer-monomer switch. Exhibiting the capability of self-delivery and resistance to nuclease degradation, the nanoprobe has been successfully applied for microRNA imaging in live cells.


Assuntos
Sondas de DNA/química , MicroRNAs/metabolismo , Nanoestruturas/química , Linhagem Celular Tumoral , Sondas de DNA/metabolismo , Corantes Fluorescentes/química , Humanos , MicroRNAs/química , Microscopia Confocal , Pirenos/química
17.
Photochem Photobiol Sci ; 19(1): 105-113, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31930262

RESUMO

We report on the light-switch behaviour of two head-to-tail expanded bipyridinium species as a function of their interaction with calf thymus DNA and polynucleotides. In particular, both DNA and polynucleotides containing exclusively adenine or guanine moieties quench the luminescence of the fused expanded bipyridinium species. This behaviour has been rationalized demonstrating that a reductive photoinduced electron transfer process takes place involving both adenine or guanine moieties. The charge separated state so produced recombines in the tens of picoseconds. These results could help in designing new organic substrates for application in DNA probing technology and lab on chip-based sensing systems.


Assuntos
Sondas de DNA/química , DNA/análise , Corantes Fluorescentes/química , Imagem Óptica , Compostos de Piridínio/química , Animais , Bovinos , Sondas de DNA/síntese química , Corantes Fluorescentes/síntese química , Estrutura Molecular , Oxirredução , Compostos de Piridínio/síntese química , Espectroscopia de Luz Próxima ao Infravermelho , Raios Ultravioleta
18.
Talanta ; 209: 120550, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31891998

RESUMO

Developing the high selectivity and sensitivity strategy for nucleic acid detection is crucial for early diagnosis and therapy of diseases. In this work, a novel low back-ground fluorescent sensor platform for the detection of nucleic acid has been developed based on δ-FeOOH nanosheets integrating with exonuclease III-assisted target-recycling signal amplification. Because of the strong binding ability between the single-strand DNA (ssDNA) and the δ-FeOOH nanosheets, the dye-labeled ssDNA probe would be quenched by δ-FeOOH nanosheets through fluorescence resonance energy transfer (FRET). By using magnetic separate properties of δ-FeOOH, the background signal was separated from the sensor system, and the low background sensor system was obtained. After adding the target DNA, a double-strand DNA complex (dsDNA) would be formed between the target DNA and dye-labeled ssDNA probe. Then, the dye-labeled ssDNA probe in the dsDNA complex would be stepwise hydrolyzed into short fragments from 3'-terminus by Exonuclease III, and the fluorescence signal was recovered due to the weak bind affinity between the short fragments and δ-FeOOH nanosheets. By using the fluorescence quenching ability of δ-FeOOH nanosheets and enzyme-assisted target-recycling signal amplification, this strategy could show an excellent selectivity toward hepatitis C virus DNA with a low detection limit of 10 pM. By simply changing the dye-labeled ssDNA probe sequence, this sensing platform can be developed as a universal approach for the simple, sensitive, and selective detection of different target DNA.


Assuntos
DNA Viral/sangue , Exodesoxirribonucleases/química , Compostos Férricos/química , Hepacivirus/isolamento & purificação , Hepatite C/sangue , Técnicas Biossensoriais/métodos , Sondas de DNA/química , DNA de Cadeia Simples/química , DNA Viral/análise , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/química , Hepatite C/virologia , Humanos , Limite de Detecção , Nanoestruturas/química
19.
Chem Commun (Camb) ; 56(8): 1175-1178, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31919487

RESUMO

We developed a bright carbon nanodot-based miRNA detection method with signal amplification by concatenated hybridization chain reaction (CHCR). In the presence of target miRNA, CHCR was triggered and a frond-like DNA product was formed, which recovered remarkable fluorescence. The location and level of the target miRNA were then indicated.


Assuntos
Carbono/química , MicroRNAs/análise , Pontos Quânticos/química , DNA/química , DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , Humanos , Limite de Detecção , Células MCF-7 , MicroRNAs/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico , Espectrometria de Fluorescência/métodos
20.
Anal Bioanal Chem ; 412(4): 915-922, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31900531

RESUMO

A tetrahedral DNA probe can effectively overcome the steric effects of a single-stranded probe to obtain well-controlled density and minimize nonspecific adsorption. Herein, a highly sensitive electrochemical biosensor is fabricated for determination of protein using a tetrahedral DNA probe and rolling circle amplification (RCA). N- and P-co-doped graphene (NP-rGO) is prepared, and AuNPs are then electrodeposited on it for DNA probe immobilization. Benefitting from the synergistic effects of the excellent electrical conductivity of NP-rGO, the stability of the tetrahedral DNA probe and the signal amplification of RCA, the biosensor achieves a low limit of 3.53 × 10-14 M for thrombin and a wide linear range from 1 × 10-13 to 1 × 10-7 M. This study provides a sensitive and effective method for the detection of protein in peripheral biofluids, and paves the way for future clinical diagnostics and treatment of disease. Graphical abstract.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Grafite/química , Trombina/análise , Sondas de DNA/química , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Ácidos Nucleicos Imobilizados/química , Limite de Detecção , Nanopartículas Metálicas/química , Técnicas de Amplificação de Ácido Nucleico/métodos
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