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1.
Anal Bioanal Chem ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38676824

RESUMO

Exploring the construction of an interface with bright emission, fabulous stability, and good function to develop high-performance electrochemiluminescence (ECL) biosensors for tumor biomarkers is in high demand but faces a huge challenge. Herein, we report an oriented attachment and in situ self-assembling strategy for one-step fabrication of CdTe QD-encapsulated Hf polymer membrane onto an ITO surface (Hf-CP/CdTe QDs/APS/ITO). Hf-CP/CdTe QDs/APS/ITO is fascinating with excellent stability, high ECL emission, and specific adsorption toward ssDNA against dsDNA and mononucleotides (mNs). These interesting properties make it an ideal interface to rationally develop an immobilization-free ECL biosensor for cancer antigen 125 (CA125), used as a proof-of-concept analyte, based on target-aptamer recognition-promoted exonuclease III (Exo III)-assisted digestion. The recognition of ON by CA125 leads to the formation of CA125@ON, which hybridizes with Fc-ssDNA to switch Exo III-assisted digestion, decreasing the amount of Fc groups anchored onto the electrode's surface and blocking electron transfer. As compared to the case where CA125 was absent, significant ECL emission recovery is determined and relies on CA125 concentration. Thus, highly sensitive analysis of CA125 against other biomarkers was achieved with a limit of detection down to 2.57 pg/mL. We envision this work will provide a new path to develop ECL biosensors with excellent properties, which shows great potential for early and accurate diagnosis of cancer.

2.
Anal Chem ; 95(17): 7014-7020, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37072890

RESUMO

The peroxidase (POD)-like nanozyme typically requires the addition of exogenous H2O2. To address the limitation, previous work mainly adopted a cascade strategy for H2O2 production. Herein, we propose a new light-driven self-cascade strategy to construct POD-like nanozymes without exogenous H2O2. The model nanozyme resorcinol-formaldehyde resin-Fe3+ (RF-Fe3+) is synthesized with the hydroxyl-rich photocatalytic material RF as the carrier to in situ chelate metal oxides, which can simultaneously achieve the functions of in situ H2O2 generation under irradiation and substrate oxidation via POD-like behavior. Notably, RF-Fe3+ exhibits high affinity to H2O2, attributed to the excellent adsorption ability and hydroxyl-rich feature of RF. Furthermore, the dual photoelectrode-assisted photofuel cell was further constructed with a high-power density of 120 ± 5 µW cm-2 based on the RF-Fe3+ photocathode. This work not only demonstrates the new self-cascade strategy of in situ generation of catalysis substrates but also provides an opportunity to extend the catalytical field.


Assuntos
Peróxido de Hidrogênio , Peroxidase , Peroxidases , Adsorção , Catálise , Corantes , Radical Hidroxila
3.
Anal Chem ; 95(42): 15763-15768, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37816228

RESUMO

Classical luminol-based chemiluminescence (CL) is the process of emitting light enhanced by the addition of coreactant hydrogen peroxide (H2O2). To address the instability issue of H2O2 decomposition, herein, we proposed a nanozyme-based biofuel cell (BFC) ingeniously coupled with a luminol CL system via in situ generation of H2O2. Specifically, the gold nanoparticle (AuNP) nanozyme with glucose oxidase-like activity can act as the anodic enzyme of BFC to catalyze the oxidation of glucose to produce H2O2 and electrons. In this case, H2O2 as a coreactant enhanced the CL intensity and the cathode of the BFC obtained electrons to generate the open circuit voltage (EOCV) signals. As a result, a dual-signal biosensing platform was successfully constructed. Interestingly, the AuNPs-catalyzed system operates in an alkaline medium, which precisely meets the pH requirement for luminol luminescence. Such a BFC-CL system not only greatly lessens the effect of unstable exogenous H2O2 on the signal stability but also enhances the CL of luminol. Furthermore, both CL and EOCV signals present a positive correlation with the glucose concentration. Therefore, this novel BFC-CL system shows good performance for dual-signal biosensing, which would serve as a valuable guideline for the design and application of BFC-based self-powered or CL biosensors.


Assuntos
Fontes de Energia Bioelétrica , Técnicas Biossensoriais , Nanopartículas Metálicas , Luminol/química , Luminescência , Ouro/química , Peróxido de Hidrogênio/química , Nanopartículas Metálicas/química , Glucose/química , Medições Luminescentes
4.
Cell Commun Signal ; 21(1): 144, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-37328851

RESUMO

BACKGROUND: Ovarian cancer, particularly epithelial ovarian cancer (EOC), is the leading cause of cancer-related mortality among women. Our previous study revealed that high HMGB3 levels are associated with poor prognosis and lymph node metastasis in patients with high-grade serous ovarian carcinoma; however, the role of HMGB3 in EOC proliferation and metastasis remains unknown. METHODS: MTT, clonogenic, and EdU assays were used to assess cell proliferation. Transwell assays were performed to detect cell migration and invasion. Signaling pathways involved in HMGB3 function were identified by RNA sequencing (RNA-seq). MAPK/ERK signaling pathway protein levels were evaluated by western blot. RESULTS: HMGB3 knockdown inhibited ovarian cancer cell proliferation and metastasis, whereas HMGB3 overexpression facilitated these processes. RNA-seq showed that HMGB3 participates in regulating stem cell pluripotency and the MAPK signaling pathway. We further proved that HMGB3 promotes ovarian cancer stemness, proliferation, and metastasis through activating the MAPK/ERK signaling pathway. In addition, we demonstrated that HMGB3 promotes tumor growth in a xenograft model via MAPK/ERK signaling. CONCLUSIONS: HMGB3 promotes ovarian cancer malignant phenotypes and stemness through the MAPK/ERK signaling pathway. Targeting HMGB3 is a promising strategy for ovarian cancer treatment that may improve the prognosis of women with this disease. Video Abstract.


Assuntos
Proteína HMGB3 , Neoplasias Ovarianas , Transdução de Sinais , Feminino , Humanos , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/patologia , Fenótipo , Proteína HMGB3/genética
5.
Int J Mol Sci ; 24(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37511093

RESUMO

The purpose of this study is to determine the effects of red and blue lights on the photomorphogenesis and photosynthetic traits of rice seedlings. The rice seedlings were cultured with red light (R), blue light (B), combined red and blue lights (R3B1/R1B1/R1B3), and white light (CK) as the control. The combined application of red and blue lights could promote the growth of rice seedlings to varying degrees; enhance photosynthesis by increasing the seedling leaf area, chlorophyll content, and chlorophyll fluorescence; improve root characteristics by increasing root number, root volume, and root activity; and thus increase the dry matter accumulation of rice seedlings. In addition, the combination of red and blue lights could regulate the expression of genes related to photosynthesis in rice leaves, affect the activity of the Rubisco enzyme, and then affect the photosynthesis of rice seedlings. These results indicate that red and blue lights have direct synergistic effects, which can regulate the growth of rice seedlings and promote the morphogenesis of rice seedlings. The combined application of red and blue lights can be used to supplement the light in rice-factory seedling raising.


Assuntos
Oryza , Plântula , Luz , Fotossíntese/fisiologia , Clorofila/metabolismo
6.
Int J Mol Sci ; 24(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37445882

RESUMO

The purpose of this study is to determine the effect of light quality on growth, carbon and nitrogen metabolism, and antioxidant defense system of rice seedlings. Six light conditions were employed, including white (W), red (R), blue (B), combined LED of R and B at 3:1 (R3B1), combined LED of R and B at 1:1 (R1B1), as well as combined LED of R and B at 1:3 (R1B3). Combined application of red light and blue light could promote the growth of rice seedling leaves and roots under low light stress to varying degrees, increase the photosynthetic area by increasing the leaf area, improve the root characteristics by increasing the root volume, and increase the dry matter accumulation of rice seedlings. In addition, the combination of red light and blue light could increase carbon and nitrogen metabolites in rice seedling leaves, regulate the expression of genes related to carbon and nitrogen metabolism and enzyme activity, and enhance the antioxidant enzyme activity of rice seedlings. These results indicate that red light and blue light directly have synergistic effects which can regulate the carbon and nitrogen metabolism of rice seedlings, promote the morphogenesis of rice seedlings under low light stress, and promote growth, which has never been reported in previous studies. This study is a new discovery in the application of light quality in crop production and provides new avenues to enhance crop stress resistance. However, further study is needed to explore the physio-biochemical and molecular mechanisms of light quality in crop production.


Assuntos
Oryza , Plântula , Plântula/genética , Oryza/genética , Antioxidantes , Carbono , Nitrogênio
7.
Anal Chem ; 94(3): 1654-1660, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35025211

RESUMO

Photo-assisted biofuel cell-based self-powered biosensors (PBFC-SPBs) possess the advantages of no need for external power supply, ease of sensing design, and simple instruments. In this work, a robust anti-interference PBFC-SPB for microRNA detection was constructed based on the Pt-S bond and the inorganic-organic hybridization strategy. The organic semiconductor [6,6]-phenyl-C61-butyric acid methylester@anthraquinone (PCBM@anthraquinone) served as an efficient light-harvesting material, and gold nanoparticle@Pt (AuNP@Pt) nanomaterials were immobilized on the surface via electrostatic adsorption for the binding of DNA. Notably, compared to Au-S bonds for DNA immobilization, the Pt-S bond exhibited better anti-interference ability. Ingeniously, cadmium sulfide quantum dots (CdS QDs) were close to the PCBM@anthraquinone substrate electrode to form sensitization structures, which was beneficial to enhance the photocurrent signal. Combining with the laccase-mimicking activity Cu2+/carbon nanotubes (Cu2+/CNTs) cathode, the PBFC-SPB for microRNA detection was achieved. Once the target existed, the identical sequence complementary microRNA would make DNA2/CdS dissociate and break away from the electrode, leading to a low signal. The linear detection range was 10 fM-100 pM, with the limit of determination of 2.4 fM (3S/N). The as-proposed strategy not only paves a new way for the design of photoelectrochemical biosensing but also opens a door for the construction of robust anti-interference bioassay for microRNA detection.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , MicroRNAs , Nanotubos de Carbono , Pontos Quânticos , Técnicas Eletroquímicas , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Pontos Quânticos/química
8.
Small ; 18(3): e2104993, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34837456

RESUMO

Metal-free carbon nanozymes could be promising with the unique features of intrinsic catalytic ability, structure diversity, and strong tolerance to acidic/alkaline media. However, to date, the study of metal-free carbon nanozymes fell far behind metal-based nanomaterials, in which, the majority reported much more peroxidase-like activity than other enzyme-mimicking behavior (e.g., oxidase). Thus, the exploit of high-performance carbon nanozymes is of importance but challenging. In this work, the nitrogen-rich conjugated polymer (Aza-CPs) with rigid network structure is utilized as precursor to yield N-doped carbon material QAU-Z1 in high yield via a direct pyrolysis method. Surprisingly, QAU-Z1 stood out in oxidase-like behavior, which significantly outperformed the control materials GNC-900 and QAU-Z2 with nucleobase or conjugated small molecule as precursor, respectively. More importantly, it is a crucial revelation that the catalytic performance is closely related to the change of zeta potential for carbon nanozyme during the substrate 3,3',5,5'-tetramethylbenzidine oxidation process, as well as its catalytical capacity to O2 , which could be insightful to understand the inherent mechanism. This work not only presents the potential of conjugated polymers in constructing highly efficient carbon nanozyme, but also reveals the vital role of interaction mode between the nanozyme and substrate in the catalytic performance.


Assuntos
Carbono , Nanoestruturas , Carbono/química , Catálise , Nitrogênio/química , Oxirredutases , Polímeros
9.
Anal Chem ; 93(34): 11745-11750, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34405678

RESUMO

Electrochemiluminescence (ECL) is one powerful tool in the sensing field, in which the electrochemical workstation is necessary to achieve the electrical/optical signal conversion in the presence of luminescent agents. By contrast, biofuel cells (BFCs) can also provide electricity from renewable biofuels under moderate conditions. More importantly, BFCs with the features of adjustable voltage output and excellent compatibility would well meet the requirement of working voltages for different ECL devices. However, to the best of our knowledge, the BFC-driven luminous system has not been reported. In this work, we constructed, for the first time, a BFC-driven ECL system with fast and stable signal outputs. To demonstrate the proof-of-concept of the BFC-ECL system, the sensitive and selective detection of histidine was achieved, exhibiting great potential among point-of-care diagnoses in remote regions. Overall, this work not only paves a new way for the conversion of chemical energy, electrical energy, and luminous system but also explores the new application of BFC.


Assuntos
Fontes de Energia Bioelétrica , Técnicas Biossensoriais , Substâncias Luminescentes , Técnicas Eletroquímicas , Medições Luminescentes
10.
Anal Chem ; 93(36): 12441-12446, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34464093

RESUMO

The classic luminol-based electrochemiluminescence (ECL) platform generally suffers from self-decomposition of the coreactant (i.e., H2O2) during the reaction process, seriously hampering the luminous signal stability, as well as its practical application. To address this issue, apart from the introduction of complex exogenous species, preoxidation of the luminophore, and electrocatalysis for ECL signal amplification, we proposed a novel ECL model to realize the signal enhancement via in situ self-photocatalytic generation of the coreactant H2O2. Interestingly, the luminescence of luminol was simultaneously utilized as the light source to promote the conversation of O2 to H2O2 with the assistance of the photocatalyst resorcinol-formaldehyde resin, which could further improve the luminescence of luminol in turn. In comparison with the traditional case, this new ECL model not only exhibited obvious signal amplification but also efficiently boosted its stability of signal output. To sum up, an exogenous coreactant-free, highly stable ECL platform was obtained via simply integrating the photocatalyst RF and the luminol-based system. This work will not only inspire the design of a new integrated ECL system with a coreactant translator but also provide an ingenious insight for the construction of a new generation of ECL models.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Peróxido de Hidrogênio , Medições Luminescentes , Luminol
11.
Anal Chem ; 92(7): 5426-5430, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32133847

RESUMO

Aberrant DNA methylation catalyzed by DNA methyltransferases (MTase) has proved to be associated with human diseases such as cancers. Thus, the development of an efficient strategy to accurately detect DNA MTase is highly desirable in medical diagnostics. Herein, we proposed a robust "signal-on" enzymatic biofuel cell (EBFC)-based self-powered biosensing platform with excellent anti-interference ability for DNA MTase activity analysis and inhibitor screening. In the presence of target MTase, the MTase-catalyzed DNA methylation occurred and hindered the HpaII endonuclease-catalyzed dsDNA dissociation, which enabled more bilirubin oxidase (BOD) to immobilize at the cathode surface via amidation. Then, BOD-catalyzed oxygen reduction took place by accepting electrons generated at the anode via glucose oxidation, thus leading to an elevated open-circuit voltage value, the amplitude of which was directly related to MTase concentration. The direct detection limit of the M.SssI assay was down to 0.005 U/mL, which was lower than that of those reported results. Notably, the as-proposed protocol was competent to detect DNA MTase activity directly in human serum samples without enrichment and separation, and applicable to the screening of M.SssI inhibitors. Considering the virtues of the excellent anti-interference ability, no requirement of external power, simplicity, and high accuracy, the biosensing platform would hold great potential in DNA MTase bioassay and clinical diagnosis of cancers.


Assuntos
Fontes de Energia Bioelétrica , Técnicas Biossensoriais/métodos , Metilases de Modificação do DNA/antagonistas & inibidores , Metilases de Modificação do DNA/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios Enzimáticos/métodos , Inibidores Enzimáticos/farmacologia , Metilases de Modificação do DNA/sangue , Humanos
12.
Angew Chem Int Ed Engl ; 59(18): 7224-7229, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32065712

RESUMO

An organic semiconductor-bacteria biohybrid photosynthetic system is used to efficiently realize CO2 reduction to produce acetic acid with the non-photosynthetic bacteria Moorella thermoacetica. Perylene diimide derivative (PDI) and poly(fluorene-co-phenylene) (PFP) were coated on the bacteria surface as photosensitizers to form a p-n heterojunction (PFP/PDI) layer, affording higher hole/electron separation efficiency. The π-conjugated semiconductors possess excellent light-harvesting ability and biocompatibility, and the cationic side chains of organic semiconductors could intercalate into cell membranes, ensuring efficient electron transfer to bacteria. Moorella thermoacetica can thus harvest photoexcited electrons from the PFP/PDI heterojunction, driving the Wood-Ljungdahl pathway to synthesize acetic acid from CO2 under illumination. The efficiency of this organic biohybrid is about 1.6 %, which is comparable to those of reported inorganic biohybrid systems.


Assuntos
Ácido Acético/metabolismo , Dióxido de Carbono/metabolismo , Moorella/metabolismo , Fármacos Fotossensibilizantes/metabolismo , Energia Solar , Ácido Acético/química , Dióxido de Carbono/química , Transporte de Elétrons , Fluorenos/química , Fluorenos/metabolismo , Imidas/química , Imidas/metabolismo , Estrutura Molecular , Moorella/citologia , Oxirredução , Perileno/análogos & derivados , Perileno/química , Perileno/metabolismo , Fármacos Fotossensibilizantes/química , Polímeros/química , Polímeros/metabolismo , Semicondutores , Propriedades de Superfície
13.
Anal Chem ; 91(13): 8697-8704, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31247724

RESUMO

Enzymatic biofuel cell (EBFC)-based self-powered biosensors could offer significant advantages: no requirement for an external power source, simple instruments, and easy miniaturization. However, they also suffered from the limitations of lower sensitivity or specific targets. In this study, a self-powered biosensor for the ultrasensitive and selective detection of single nucleotide polymorphisms (SNPs) produced by combining the toehold-mediated strand displacement reaction (SDR) and DNA hybridization chain reaction (HCR) was proposed. Herein, the capture probe (CP) with an external toehold was designed to switch on the sensing system. In the presence of target sequence, both SDR and DNA HCR reaction would happen to produce a long double-helix chain. Because of the electrostatic interaction between [Ru(NH3)6]3+ and the double-helix chain described above, the open circuit voltage ( EOCV) of the as-proposed biosensor was significantly elevated, thus realizing the detection of SNPs. Overall, in this work, an ingeniously constructed self-powered biosensor for the detection of SNPs was created by integrating EBFCs with a DNA amplification strategy. Furthermore, the as-proposed self-powered biosensor not only showed prominent specificity to distinguish the p53 gene fragment from random sequences (e.g., single-base mutant sequences) but exhibited excellent sensitivity with the detection limit of 20 aM. More importantly, the results obtained from the real cell lysate sample have laid a strong foundation for disease diagnostics and, potentially, as a powerful tool for even more fields.


Assuntos
Fontes de Energia Bioelétrica , Técnicas Biossensoriais/métodos , DNA/análise , Técnicas Eletroquímicas/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Polimorfismo de Nucleotídeo Único , DNA/genética , Células HeLa , Humanos , Limite de Detecção , Hibridização de Ácido Nucleico
14.
Chem Soc Rev ; 46(5): 1545-1564, 2017 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-28211932

RESUMO

During the past decade, biofuel cells (BFCs) have emerged as an emerging technology on account of their ability to directly generate electricity from biologically renewable catalysts and fuels. Due to the boost in nanotechnology, significant advances have been accomplished in BFCs. Although it is still challenging to promote the performance of BFCs, adopting nanostructured materials for BFC construction has been extensively proposed as an effective and promising strategy to achieve high energy production. In this review, we presented the major novel nanostructured materials applied for BFCs and highlighted the breakthroughs in this field. Based on different natures of the bio-catalysts and electron transfer process at the bio-electrode surfaces, the fundamentals of BFC systems, including enzymatic biofuel cells (EBFCs) and microbial fuel cells (MFCs), have been elucidated. In particular, the principle of electrode materials design has been detailed in terms of enhancing electrical communications between biological catalysts and electrodes. Furthermore, we have provided the applications of BFCs and potential challenges of this technology.

15.
Anal Chem ; 89(3): 2163-2169, 2017 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-28208296

RESUMO

Herein, we reported a novel ultrasensitive one-compartment enzyme biofuel cells (EBFCs)-based self-powered aptasensing platform for antibiotic residue detection. By taking full advantage of the unique features of both EBFCs-based self-powered sensors and aptamers, the as-proposed aptasensing platform has the merits of simple instrumentation, anti-interference ability, high selectivity, and low cost. In this study, DNA bioconjugate, i.e., SiO2@gold nanoparticles-complementary strand of aptamer (SiO2@AuNPs-csDNA), was elaborately designed and played a key role in blocking the mass transport of glucose to the bioanode. While in the presence of the target antibiotic, SiO2@AuNPs-csDNA bioconjugate broke away from the bioanode due to the aptamer recognition of the target. Without the blocking of glucose by the DNA bioconjugate, a significantly elevated open circuit voltage of the EBFCs-based aptasensor was obtained, whose amplitude was dependent on the antibiotic concentration. In addition, this proposed aptasensor was the first reported self-powered aptasensing platform for antibiotic determination and featured high sensitivity owing to the elaborate design of the DNA bioconjugate modified bioanode of EBFC, which was superior to those previously reported in the literature. Furthermore, due to the anti-interference ability and the excellent selectivity of the aptasensor, no special sample pretreatment was needed for the detection of antibiotics in milk samples. Therefore, the proposed EBFCs-based self-powered aptasensor has a great promise to be applied as a powerful tool for on-site assay in the field of food safety.


Assuntos
Antibacterianos/análise , Aptâmeros de Nucleotídeos/química , Fontes de Energia Bioelétrica , DNA/química , Resíduos de Drogas/análise , Enzimas/química , Técnicas Biossensoriais , Eletrodos , Glucose/química , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Dióxido de Silício/química
16.
Anal Chem ; 89(22): 12293-12298, 2017 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-29032677

RESUMO

A new label-free and enzyme-free ratiometric homogeneous electrochemical microRNA biosensing platform was constructed via target-triggered Ru(III) release and redox recycling. To design the effective ratiometric dual-signal strategy, [Ru(NH3)6]3+ (Ru(III)), as one of the electroactive probes, was ingeniously entrapped in the pores of the positively charged mesoporous silica nanoparticle (PMSN), and another electroactive probe, [Fe(CN)6]3- (Fe(III)), was selected to facilitate Ru(III) redox recycling due to its distinctly separated reduction potential and different redox properties. Owing to the liberation of the formed RNA-ssDNA complex from PMSN, the target miRNA triggered the Ru(III) release and was quickly electroreduced to Ru(II), and then, the in-site-generated Ru(II) could be chemically oxidized back to Ru(III) by Fe(III). Thus, with the release of Ru(III) and the consumption of Fe(III), a significant enhancement for the ratio of electroreduction current [Ru(NH3)6]3+ over [Fe(CN)6]3- (IRu(III)/IFe(III)) value was observed, which was dependent on the concentration of the target miRNA. Consequently, a simple, accurate, and ultrasensitive method for the miRNA assay was readily realized. Furthermore, the limit of detection (LOD) of our method was down to 33 aM (S/N = 3), comparable or even superior to other approaches reported in literature. More importantly, it also exhibited excellent analytical performance in the complex biological matrix cell lysates. Therefore, this homogeneous biosensing strategy not only provides an ingenious idea for realizing simple, rapid, reliable, and ultrasensitive bioassays but also has a great potential to be adopted as a powerful tool for precision medicine.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , MicroRNAs/análise , Rutênio/química , Humanos , MicroRNAs/genética , Oxirredução , Reação em Cadeia da Polimerase em Tempo Real , Células Tumorais Cultivadas
17.
Anal Chem ; 87(5): 3019-26, 2015 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-25669135

RESUMO

We report an electrochemical sensor for telomerase activity detection based on spherical nucleic acids gold nanoparticles (SNAs AuNPs) triggered mimic-hybridization chain reaction (mimic-HCR) enzyme-free dual signal amplification. In the detection strategy, SNAs AuNPs and two hairpin probes were employed. SNAs AuNPs as the primary amplification element, not only hybridized with the telomeric repeats on the electrode to amplify signal but also initiated the subsequent secondary amplification, mimic-hybridization chain reaction of two hairpin probes. If the cells' extracts were positive for telomerase activity, SNAs AuNPs could be captured on the electrode. The carried initiators could trigger an alternative hybridization reaction of two hairpin probes that yielded nicked double helices. The signal was further amplified enzyme-free by numerous hexaammineruthenium(III) chloride ([Ru(NH3)6](3+), RuHex) inserting into double-helix DNA long chain by electrostatic interaction, each of which could generate an electrochemical signal at appropriate potential. With this method, a detection limit of down to 2 HeLa cells and a dynamic range of 10-10,000 cells were achieved. Telomerase activities of different cell lines were also successfully evaluated.


Assuntos
Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Nanopartículas Metálicas/química , Hibridização de Ácido Nucleico/métodos , Ácidos Nucleicos/química , Telomerase/metabolismo , Técnicas Biossensoriais/métodos , Células HeLa , Humanos , Limite de Detecção , Compostos de Rutênio/química
18.
Analyst ; 140(6): 1822-6, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25670240

RESUMO

A high power output, membrane-less formic acid/O2 enzymatic biofuel cell was fabricated, in which nitrogen-doped graphene was proven to be effective for recycling the NAD(+)/NADH cofactor at a nitrogen-doped graphene/gold nanoparticle/formate dehydrogenase bioanode in the catalytic oxidation of formic acid.


Assuntos
Fontes de Energia Bioelétrica , Formiato Desidrogenases/metabolismo , Ouro/química , Grafite/química , Nanopartículas Metálicas/química , Nitrogênio/química , Oxigênio/metabolismo , Desenho de Equipamento , Formiatos/metabolismo , Nanopartículas Metálicas/ultraestrutura , Oxirredução
19.
Biosens Bioelectron ; 220: 114850, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36332338

RESUMO

Human epidermal growth factor receptor 2 (HER2) has been regarded as the considerable biomarker of breast and gastric cancer. Thus, precise detection of HER2 is of significance for the early diagnosis and treatment. Here, a photofuel cell-based self-powered biosensor (PFC-SPB) was constructed for the ultrasensitive HER2 detection, which was composed of a plasmonic gold nanoparticles (Au NPs)/organic semiconductor hybrid photoanode and a cathode with biosensing strategy of electrochemical sandwich structure. The localized surface plasmon resonance effect of Au NPs can obviously enhance the separation efficiency of photo-generated electron/hole pair, which was beneficial to the sensitivity and stability of PFC-SPB. Meanwhile, the cathodic sandwich structure not only was used for the target recognition, but also can guarantee the enrichment of electroactive molecules (molybdophosphate). Consequently, with the open circuit voltage (EOCV) as the output signal, the PFC-SPB can achieve the HER2 detection in the range of 0.1-500 pg mL-1 with a low detection limit of 0.02 pg mL-1. Moreover, the as-proposed bioassay can be applied in cell lysate sample without any pretreatment, providing a promising and powerful tool early clinical diagnosis of cancer.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Humanos , Ouro/química , Nanopartículas Metálicas/química , Receptor ErbB-2 , Técnicas Eletroquímicas , Limite de Detecção
20.
Biosens Bioelectron ; 220: 114841, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36323162

RESUMO

Enzyme-mediated dephosphorylation reaction is the important approach to realize the inactivation and detection of hazardous phosphate chemicals. To date, many phosphatases-like nanozymes (e.g., CeO2) have demonstrated the catalytic hydrolysis ability of the phosphomonoesters, rather than phosphotriester, and the CeO2 nanozyme only work under relatively harsh conditions of high temperature, and large dosage. Thus, exploration of efficient nanozymes for the rapid dephosphorylation of phosphotriester under mild conditions remains a challenge. Here, a novel CeO2@NC nanozyme is developed with excellent phosphatases-like activity based on substrate synergistic effect, in which, CeO2 nanoparticles embedded in N-doped carbon (NC) material. Taking paraoxon as the model substrate, such CeO2@NC nanozyme can drive rapid dephosphorylation of phosphotriester over a broad temperature range, which not only significantly outperforms natural phosphatases and neat CeO2, but also can preserve >80% of the optimal activity after exposure of harsh conditions, such as strong acidic/basic medium, high temperature of up to 80 °C. The excellent catalytic performance could be due to that Ce(IV)/Ce(III) species act as the active sites to realize the polarization and hydrolysis of P-O bond while NC template works as the synergistic group to adsorb the substrate. Furthermore, a simple colorimetric assay is developed for the rapid and selective detection of paraoxon. Overall, this work not only develops a highly efficient phosphatases-like nanozyme via substrate synergetic strategy, but also opens an interesting avenue for the rapid detection of organophosphorus pesticides.


Assuntos
Técnicas Biossensoriais , Cério , Praguicidas , Paraoxon , Colorimetria , Cério/química , Compostos Organofosforados , Praguicidas/análise , Monoéster Fosfórico Hidrolases
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