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1.
ACS Appl Mater Interfaces ; 13(33): 39719-39729, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34392680

RESUMO

In this work, cucurbiturils (CBs), a class of macrocyclic supramolecules, were observed to have an interesting peroxidase-like activity, which is metal-free, substrate-specific, thermophilic, acidophilic, and insensitive to ionic strength. By coating CBs on enzyme-encapsulated zeolitic imidazolate framework-8 (ZIF-8), a composite nanozyme was constructed, which retains the catalytic ability of CBs and enzymes and makes them cascade. On addition of the substrate, i.e., the detection target, a highly efficient cascade catalysis can be launched in all the spatial directions to generate sensitive and visible signals. Convenient detection of glucose and cholesterol as models is thereby achieved. More importantly, we have also successfully constructed a composite nanozyme-based sensor array (6 × 8 wells) and thereby achieved simultaneous colorimetric analysis of multiple samples. The concept and successful practice of the construction of the unique core-shell supramolecule/biomolecule@nanomaterial architecture provide the possibility to fabricate next-generation multifunctional materials and create new applications by integrating their unique functions.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Imidazóis/química , Nanocompostos/química , Peroxidases/química , Zeolitas/química , Técnicas Biossensoriais , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Catálise , Colorimetria , Corantes Fluorescentes/química , Glucose Oxidase/química , Glucose Oxidase/metabolismo , Peróxido de Hidrogênio/química , Imidazóis/metabolismo , Simulação de Acoplamento Molecular , Oxirredução , Peroxidases/metabolismo , Impressão Tridimensional
2.
Biosens Bioelectron ; 189: 113379, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34091284

RESUMO

Herein, for the first time, we propose that the cleavage activity of DNAzyme is accompanied by the release of hydroxyl ions, which can be used for colorimetric assay. Subsequently, we further construct a colorimetric strategy for lipopolysaccharide (LPS) analysis by using this property. Detailly, DNAzyme is split into two fragments separately modified with aldehyde group and hydroxylamine group, which can be linked together through oxime chemistry and the presence of LPS can prevent the formation of oxime bond. The formed whole DNAzyme can mediate the release of hydroxyl ions serving for colorimetric signal output. Taking LPS as model targets, DNAzyme-based colorimetric assay has been successfully constructed. This work not only provides a colorimetric strategy to analyze DNAzyme activity, but also gives a new insight to enrich the versatility of DNAzymes and to enhance their multifunctionality.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Colorimetria , Lipopolissacarídeos , Oximas
3.
Crit Rev Anal Chem ; 51(1): 8-19, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-31613139

RESUMO

Cancer is a global disease which has been disturbing researchers in medicine and seriously threatens patients' health and lifetime around the world in the past several decades. Due to the characteristics of cancer cells, such as uncontrollable cell proliferation, cell invasion and metastasis to surrounding tissues, lower grade of differentiation, higher telomerase activity and others, it has been one of the most usual lethal factors, next to heart disease in incidence. Cancer mortality can be decreased by early diagnosis, and the people who with treatment at an early stage have an obvious improved survival rate. Consequently, early detection is significant for better understanding the pathogenesis of cancer and improving the prognosis of patients. In situ detection technique is a vital tool for imaging and cellular pathology research, which can provide effective information about tumor markers in the early cancer detection. In view of low expression of most tumor markers in the early stage of cancers, detection techniques based on DNA signal amplification and DNA nanodevices can provide a strong support for the diagnosis and detection of cancers. In this review, we summarize the research progress of different analytical techniques for detecting various tumor markers that have been reported in recent years. We compare different DNA amplification and nanodevices, then provide guidance and suggestions for better understanding in situ analysis of cancer cells.

4.
Chembiochem ; 22(7): 1302-1306, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33242223

RESUMO

In this study, a tetrahedral DNA nanostructure was first self-assembled; this was then conjugated with gold nanoparticles (AuNPs) and carbon nanodots (CDs). The fabricated nanocomposites allow simultaneous analysis of telomerase activity and miRNA with dual fluorescence channels. By further introducing an iRGD peptide sequence, the nanoconjuates can be conveniently transferred inside living cells for in situ imaging. The analytical performances and anti-jamming capabilities are excellent. Meanwhile, the materials are highly biocompatible for intracellular applications. Therefore, the proposed biosystem shows great promise as a powerful tool for quantitative analysis of the dual biomarkers. The strategy can also be further exploited as a versatile platform for in situ detection of many other targets for early disease diagnosis.

5.
Lab Chip ; 21(1): 154-162, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33230512

RESUMO

Balancing operability and performance has long been a focus of research in bioanalysis and biosensing. In this work, between the traditional wet chemistry and dry chemistry, we develop a semi-dry smart biosensing platform with favourable operability and performance for metal ions detection. This platform is based on the integration of a stimuli-responsive hydrogel with intelligent image recognition. The hydrogel consists of agarose as a matrix and well-designed fluorescent DNA probes as response elements. Target metal ions in a test sample can diffuse into the hydrogel and activate the DNA probes, outputting fluorescence signals for intelligent imaging. In this way, sensitive and convenient detection of metal ions such as potassium ions (K+) and mercury ions (Hg2+) can be achieved without the assistance of huge instruments and professional workers. The detection limits for K+ and Hg2+ are 0.34 mM and 5.6 nM, respectively. Detection of ions in serum and lake water is also available. Moreover, the hydrogel-based biosensing platform exhibits favorable selectivity, anti-degradation ability, and long-term stability. High-throughput testing can be also achieved by punching multiple test microwells in a single piece of hydrogel. The concept and successful practice of a semi-dry chemistry-based strategy make up for the shortcomings of wet chemistry and dry chemistry, and provide a promising approach for on-site testing.


Assuntos
Técnicas Biossensoriais , Mercúrio , Humanos , Hidrogéis , Íons , Espectrometria de Fluorescência
6.
Anal Chem ; 93(2): 1110-1119, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33337155

RESUMO

Nondestructive analysis of the single-cell molecular phenotype of circulating tumor cells (CTCs) is of great significance to the precise diagnosis and treatment of cancer but is also a huge challenge. To address this issue, here, we develop a facile analysis system that integrates CTCs' capture and molecular phenotype analysis. An isothermal nucleic acid amplification technique named self-folding induced release reaction (sFiR), which has high-efficiency signal amplification capabilities and can run under physiological conditions, is first developed to meet the high requirements for sensitivity and nondestructivity. By combining the sFiR with immune recognition and a single cell capture microchip, the molecular phenotype analysis of a single CTC is realized. As a model, nondestructive analysis of junction plakoglobin (JUP), an overexpressed membrane protein that is closely related to the metastasis of CTCs, is successfully achieved. Results reveal that this sFiR-based analysis system can clearly distinguish the expression of JUP in different cancer cell lines and can present quantitative information on the expression of JUP. Furthermore, the captured and analyzed CTCs maintain their basic physiological activity and can be used for drug sensitivity testing. Considering the excellent performance and ease of operation of the system, it can provide technical support for CTC-based cancer liquid biopsy and drug development.


Assuntos
Separação Celular , Células Neoplásicas Circulantes/patologia , Análise de Célula Única , gama Catenina/análise , Humanos , Células Tumorais Cultivadas
7.
ACS Sens ; 5(10): 3116-3123, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-32799436

RESUMO

Due to the complexity and variability of the cellular metabolic process and the physiological environment inside and outside the cell, higher requirements are needed on the application of DNA molecular logic gate in cell analysis. In addition, heterogeneity of tumor cells tends to lead to false positives in the clinical diagnosis of a single target, even those with the same cancer type. To address these issues above, we have developed a novel DNA molecular logic gate responsive nanomachine for bispecific recognition and computation of cell membranes. Only when two membrane proteins, MUC1 and EpCAM as model proteins, exist simultaneously, the DNA molecular logic gate can be activated to perform "AND" logic operation and generate amplified "ON" fluorescence signal from the cell membrane. Therefore, our proposed dual-specific "recognition-biocomputing" DNA molecular logic gate has achieved highly accurate imaging analysis of dual-target membrane proteins in situ. Furthermore, the logic gate responsive DNA nanomachine can also be used to analyze target cells in complex cell samples with excellent specificity, which will meet the needs of biomedicine and their application in clinical diagnosis and provide new tools for the biomedical application of DNA molecular logic gates in complex cell systems.


Assuntos
Computadores Moleculares , Neoplasias , DNA/genética , Fluorescência , Lógica , Neoplasias/diagnóstico
8.
Anal Chim Acta ; 1125: 8-18, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32674784

RESUMO

Though a variety of methods have been developed for the analysis of membrane protein-protein interactions (PPIs), amplified, dynamic and nondestructive analysis in situ is always a challenge. To address this issue, here we develop a method called proximity-exponential hybridization chain reaction (PEHCR). In our strategy, when two membrane proteins approach due to interaction, they will draw their respective oligonucleotide-labeled antibodies together. The proximity of the oligonucleotides thereafter triggers a well-designed enzyme-free exponential hybridization chain reaction, which can output amplified fluorescence imaging signals. As a model, analysis of EGFR-HER2 interactions under the regulation of different activators and inhibitors is achieved. Owing to the superior signal amplification performance, we are able to clearly observe the membrane PPIs by using a common fluorescence microscope. Furthermore, unlike the existing proximity techniques that require enzymes, our enzyme-free strategy avoids the need to use a specific buffer suitable for enzyme catalysis and can be run directly in cell liquid media to maximize the physiological activity of the cells. So, dynamic analysis of membrane PPIs on living cells is achieved, and the cells, after the analysis, are still alive and are available for other usage. The successful implementation of this work enriches the toolbox for the study of membrane PPIs especially on those heterogeneous cell populations with small amount.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Receptor ErbB-2/metabolismo , Anticorpos Monoclonais/imunologia , Linhagem Celular Tumoral , Receptores ErbB/química , Receptores ErbB/imunologia , Receptores ErbB/metabolismo , Corantes Fluorescentes/química , Humanos , Microscopia Confocal , Microscopia de Fluorescência , Hibridização de Ácido Nucleico , Oligonucleotídeos/química , Oligonucleotídeos/genética , Ligação Proteica , Receptor ErbB-2/química , Receptor ErbB-2/imunologia
9.
ACS Appl Mater Interfaces ; 12(33): 36851-36859, 2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32660232

RESUMO

Electrochemical biosensing relies on electron transport on the electrode surface. However, the limited functional area of the two-dimensional electrode prevents the qualitative breakthrough in the efficiency of electron transfer. Here, a three-dimensional electron transporter was constructed to improve the efficiency of electron transfer by using an interface-immobilized DNA hydrogel. A three-dimensional pure DNA hydrogel is constructed and used as a scaffold for electron transfer. Then, an electron mediator is embedded in the DNA hydrogel through intercalative binding, and DNAzyme with intrinsic peroxidase-like activity is introduced at the node of the hydrogel scaffold to fabricate an electrochemical biosensor. The conduction of the electron mediator in the scaffold enables the acquisition of long-distance DNAzyme catalytic signals, thereby overcoming the limitation of two-dimensional electrodes. This three-dimensional electron transporter is significant for enriching the toolbox of electrochemical biosensing and can provide potential support for the development of highly sensitive biosensors.


Assuntos
Hidrogéis/química , Ácidos Nucleicos Imobilizados/química , Técnicas Biossensoriais , DNA Catalítico/metabolismo , Módulo de Elasticidade , Técnicas Eletroquímicas , Eletrodos , Transporte de Elétrons , Simulação de Acoplamento Molecular , Peroxidase/metabolismo , Propriedades de Superfície
10.
Chem Commun (Camb) ; 56(51): 6961-6964, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32436536

RESUMO

We have designed a DNA logic gate that can integrate the recognition of multiple biomarkers with signal amplification to perform the accurate and sensitive analysis of circulating tumor cells (CTCs). It also has the potential to analyze rare cells that exist in small amounts but are of great significance (such as stem cells) in the fields of clinical diagnosis and biomedicine.


Assuntos
Aptâmeros de Nucleotídeos/química , DNA/química , Células Neoplásicas Circulantes/patologia , Biomarcadores Tumorais/análise , Técnicas Biossensoriais , Células HeLa , Células Hep G2 , Humanos , Células MCF-7 , Imagem Óptica
11.
Theranostics ; 10(10): 4410-4421, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32292504

RESUMO

Non-destructive analysis of cells at the molecular level is of critical importance for cell research. At present, immunoassay-based and aptamer-based methods can achieve non-structural destructive cell analysis, but still lead to changes in cells at the molecular level. Here, we have proposed a dual-terminal amplification (DTA) strategy, which enables nondestructive analysis of membrane protein MUC1 without the effect on protein expression and cell viability in living cells. Methods: A fluorophore (Cy5)-labeled DNA ternary complex consisting of three oligonucleotides is designed. It can recognize MUC1 through its aptamer region, and thus make the MUC1 of cells visible under a fluorescence microscope. When DNA polymerase is added, dual-terminal amplification is performed. One direction dissociates aptamer from MUC1, and the other direction, also known as rolling circle amplification (RCA), produces long linear DNA strands, which can be further adopted for quantitative analysis of MUC1. In this way, all reagents are removed from the surface of the cells after the analysis, which allows nondestructive analysis. We named this strategy dual-terminal amplification (DTA) analysis. Results: By using the DTA analysis, both in situ fluorescence imaging analysis and ex situ fluorescence quantitative analysis of MUC1 were achieved. In addition, the aptamer-containing DNA ternary complex stays on cell surface only during the analysis and leaves the cell after the analysis is complete. The cells can be maintained in a non-interfering state for the rest of the time. So after the analysis, it is found that there are no effect on the physiological activity of cells and the expression of target protein even after two rounds of repeatable imaging and quantitative analysis. Conclusion: In summary, we have successfully constructed a strategy for nondestructive analysis of membrane protein in living cells. We believe that this method provides a promising way for the analysis of the key membrane proteins of cells and the versatile utilization of precious cell samples.


Assuntos
Aptâmeros de Nucleotídeos/química , Mucina-1/metabolismo , Neoplasias , Imagem Óptica/métodos , Análise de Célula Única/métodos , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/ultraestrutura
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 231: 118109, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062512

RESUMO

Puerariae Radix (PR) is a natural herb whose active ingredient is mainly flavonoids. To explore the interaction between PR flavonoids and DNA not only has important biological implications for understanding the mechanism of action, but also helps develop PR products for the design of appropriate dietary interventions to aid cancer treatment. In this work, we comprehensively studied the interaction between six kinds of PR flavonoids and DNA from four different and progressive levels, including molecular docking, multi-spectral analysis, and functional analysis in vitro and in cell. Results show that the DNA binding affinity of six flavonoids is in an order of quercetin > formononetin > daidzein > puerarin > 4'-methoxy puerarin > puerarin 6″-O-xyloside (POS), in which quercetin can significantly inhibit DNA amplification owing to its strongest binding affinity. The binding between quercetin and DNA is further revealed to be intercalated binding, which can cause conformational changes in DNA, thereby exhibiting an activity of cell cycle arrest and anti-proliferative. This property of quercetin can be utilized for the further development of flavonoids with anticancer activity. In addition to the potential application, this work also provides a platform for the comprehensive study of the interaction between micromolecules and DNA.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , DNA/metabolismo , Flavonoides/química , Flavonoides/farmacologia , Pueraria/química , Células A549 , Animais , Bovinos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , DNA/química , Células Hep G2 , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
13.
Anal Chim Acta ; 1095: 179-184, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31864620

RESUMO

Abnormal expression of specific microRNAs (miRNAs) is associated with the occurrence, development and prognosis of many diseases. In this study, a miRNA detection method based on exponential amplification reaction (EXPAR) and triplex DNA mediated aggregation of gold nanoparticles (AuNPs) was established. Specifically, one class of AuNPs is conjugated with an EXPAR probe, on which there is a complementary sequence of the target miRNA. The EXPAR reaction is triggered and duplex DNA is formed on the surface of AuNPs when the target miRNA exists. Then, single DNA probe on another class of AuNPs interacts with the duplex DNA to form triplex DNA, leading to the aggregation of the two classes of AuNPs, which could be quantified by UV-vis. The proposed method is highly selective and can afford a detection limit of 0.23 fM. Notably, all the ingredients needed for the analysis can pre-add to a tube and only 30 min is needed for the whole detection process. The method is simple, fast and with considerable selectivity and accuracy, so a great potential for this method is expected to meet the need of point-of-care testing of miRNA.


Assuntos
Colorimetria/métodos , DNA/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Linhagem Celular Tumoral , DNA/genética , Sondas de DNA/química , Sondas de DNA/genética , Ouro/química , Humanos , Limite de Detecção , MicroRNAs/genética , Mutação , Técnicas de Amplificação de Ácido Nucleico , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico
14.
Theranostics ; 9(20): 5914-5923, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534528

RESUMO

DNA walker is a powerful type of DNA nanomachine that can produce amplified signals during the "burnt-bridge"-like walking process. Despite their successful application in extracellular bioanalysis, the heterogeneity of the existing DNA walkers makes it difficult to guarantee the consistency of the results during the analysis of different cells. Methods: Here, an all-in-one homogeneous DNA walking nanomachine is reported that can be delivered into living cells for intracellular bioanalysis of miRNA without auxiliary materials. Results: This DNA walking nanomachine is constructed of gold nanoparticles on which two types of interrelated DNA tracks are assembled. The target miRNA, cancer-related miR-21, can be captured by one of the tracks (track 1) and then walk to the other track (track 2), releasing the hybrid of track 1 and track 2 from the nanoparticle to produce a signal. The walking process can proceed in a cyclic 1-2-1-2 manner and thereby produce amplified signals. Thus, sensitive imaging of the miRNA in situ can be achieved. Conclusion: Benefiting from the homogeneity of the detection system, the method can be applied for intracellular analysis without interference induced by the fluctuations of stimuli or accessorial contents.


Assuntos
DNA/análise , Ouro/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Técnicas Biossensoriais/métodos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Hibridização in Situ Fluorescente , Lisossomos/efeitos dos fármacos , Células MCF-7 , Nanopartículas Metálicas/efeitos adversos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Biosens Bioelectron ; 142: 111558, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31387027

RESUMO

A novel electrochemical biosensing method that can take into account both immunoassay and enzyme activity analysis was reported in this work for determination of the enzymatically active human apurinic/apyrimidinic endonuclease 1 (APE1). The basic principle is to design and construct a DNA catalytic hairpin assembly (CHA) triggered by APE1 catalysis in enzyme activity analysis, and the assembled DNAs are labeled with electrochemically active CdS and PbS quantum dots to output electrochemical signals. In this system, the signal generation needs to satisfy both the conditions of immunological recognition and enzymatic catalysis, providing a basis for accurate analysis of active APE1. Results show that this method can reflect the regulation of the enzyme activity and can also distinguish APE1 from its isozymes with the same enzyme activity. The concept and successful implementation of this integrated system will contribute to the research and application of APE1 in biomedicine, and provide a reference for the accurate analysis of other enzymes.


Assuntos
Anticorpos Imobilizados/química , Técnicas Biossensoriais/métodos , DNA Catalítico/química , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/análise , Pontos Quânticos/química , Compostos de Cádmio/química , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Ensaios Enzimáticos/métodos , Humanos , Imunoensaio/métodos , Chumbo/química , Sulfetos/química
16.
Neuroscience ; 417: 57-69, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31404586

RESUMO

An increasing number of studies have demonstrated the benefits of young individual-derived blood for aging-related diseases. However, the effects of young blood on the cognitive and cholinergic transmission defects in aging-associated Alzheimer's disease (AD) remain elusive. In the current study, we showed that young blood serum delivered intravenously attenuated deficits in hippocampal-dependent learning and memory, alleviated hippocampal Aß plaque pathology, restored synapse formation and synaptic plasticity, repaired the hippocampal cholinergic circuit, and triggered several canonical neuroprotective mechanisms [including repressor element 1-silencing transcription factor (REST)/Forkhead box protein O1 (FOXO1) signaling] in aged AD model mice. However, pharmacological blockage of hippocampal cholinergic activity nearly abrogated the neuroprotective actions of young blood serum in AD mice. Thus, our findings suggest that exogenous young blood serum exerts therapeutic effects on AD-associated cognitive disorders and pathology by promoting hippocampal cholinergic input and simultaneously activating other neuroprotective mechanisms.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/terapia , Transfusão de Sangue , Neurônios Colinérgicos/metabolismo , Hipocampo/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Hipocampo/fisiopatologia , Aprendizagem , Masculino , Memória , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Soro
17.
Analyst ; 144(13): 4060-4065, 2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31165121

RESUMO

In this work, we propose a novel concept and a proof-of-concept strategy for the fabrication of a pH-based immunoassay platform with a certain degree of universality and scalability to make it adaptable for different application scenarios. The immunoreactions for the target detection are converted to pH changes through an engineered and optimized isothermal nucleic acid amplification, named exponential amplification reaction (EXPAR). Thus, a variety of well-developed methods for pH analysis, e.g. pH indicators, pH-strips and pH meters, can be applied for immunoassay directly. Here, we show that this proof-of-concept strategy is applicable for both macromolecular and micromolecular antigens by adopting human platelet-derived growth factor-BB (PDGF-BB) and chloramphenicol (CAP) as the model targets, respectively. The detection can be achieved using a colorimetric pH indicator after a 15 min reaction of the immuno-triggered isothermal nucleic acid amplification. In addition, compared with the traditional enzyme-linked immunosorbent assay (ELISA), the performance of our strategy, especially the detection limits, is improved to varying degrees for different targets, making the strategy a promising alternative for diverse application scenarios of immunoassay.

18.
Chempluschem ; 84(1): 8-17, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31950739

RESUMO

Hepatocellular carcinoma (HCC) is a common type of malignant tumor with high incidence and mortality, and is the third leading cause of cancer-related death in human. High-precision detection of tumor markers, such as microRNA (miRNA), is expected to contribute to the early diagnosis of HCC as well as improve the survival rate of HCC patients. In recent years, great effort has been made to develop different methods to detect HCC-associated miRNA, in which signal amplification strategies are incorporated to realize high sensitivity. Among them, isothermal nucleic acid signal amplification is an emerging signal amplification technology which has the advantages of high amplification efficiency, good reproducibility, and easy operation for real-time analysis. Herein, we provide an overview of the advances in the application of isothermal nucleic acid signal amplification in HCC-associated miRNA detection by highlighting several representative works in recent years.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , MicroRNAs/metabolismo , Técnicas de Amplificação de Ácido Nucleico/métodos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Técnicas Biossensoriais , Carcinoma Hepatocelular/genética , Humanos , Neoplasias Hepáticas/genética , Pontos Quânticos/química , Reprodutibilidade dos Testes
19.
Anal Bioanal Chem ; 411(2): 387-393, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30382324

RESUMO

Accumulating findings demonstrate the importance of histone acetyltransferases (HATs) in regulating the acetylation of histones and reveal that their aberrant catalytic activities are involved in the occurrence and progress of numerous diseases. Herein, a feasible electrochemical method is proposed to assay the activity of HAT. The critical elements of the assay method are the hindrance of HAT-catalyzed acetylation against carboxypeptidase Y-catalyzed digestion and cucurbit[8]uril-assisted peptide assembly, which may recruit peptide-templated silver nanoparticles onto the electrode surface, producing significant electrochemical signals. Taking p300 as a model HAT, the assay method is validated to exhibit desirable selectivity, reproducibility, and usability in inhibitor analysis, and allow absolute activity determination in a linear range from 0.1 to 50 nM with a detection limit of 0.055 nM, which is lower than those of previous reports. Therefore, this work may provide an effective tool for HAT activity assay, which will be of great potential in HAT-related fundamental research, disease diagnosis, and drug development in the future. Graphical abstract ᅟ.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Técnicas Eletroquímicas , Histona Acetiltransferases/metabolismo , Imidazóis/química , Peptídeos/química , Histona Acetiltransferases/química , Reprodutibilidade dos Testes
20.
Biosens Bioelectron ; 124-125: 115-121, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30343154

RESUMO

For electrochemical biosensors, just like a computer, the modularization and coordinated operation of different components will facilitate the development of versatile biosensors and effectively reduce costs. However, the efficient synergy between different modules is always difficult. It would be a beneficial way to construct the multi-functional module. In this work, a three-dimensional gold nanoparticles/ferrocene/liposome cluster (GFLC) is fabricated and explored as a building block for the fabrication of an electrochemical biosensor, in which gold nanoparticles, ferrocene and liposome cluster work as a signal amplification component, a signal output component and a molecular recognition component, respectively. With the synergy of multi-functions, GFLC has been successfully applied for electrochemical analysis of lipopolysaccharide (LPS) in food samples. LPS can be linearly assayed in the range from 2 × 10-9 µg/mL to 8 µg/mL with a detection limit of 0.51 × 10-10 µg/mL. In view of the favorable modularization effect, GFLC shows a great potential in the development of electrochemical biosensor with considerable versatility and cost-efficiency.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Nanopartículas Metálicas/química , Compostos Ferrosos/química , Ouro/química , Limite de Detecção , Lipossomos/química , Metalocenos/química
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