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1.
Hepatology ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39024247

RESUMO

BACKGROUND AND AIMS: DILI frequently contributes to the attrition of new drug candidates and is a common cause for the withdrawal of approved drugs from the market. Although some noncytochrome P450 (non-CYP) metabolism enzymes have been implicated in DILI development, their association with DILI outcomes has not been systematically evaluated. APPROACH AND RESULTS: In this study, we analyzed a large data set comprising 317 drugs and their interactions in vitro with 42 non-CYP enzymes as substrates, inducers, and/or inhibitors retrieved from historical regulatory documents using multivariate logistic regression. We examined how these in vitro drug-enzyme interactions are correlated with the drugs' potential for DILI concern, as classified in the Liver Toxicity Knowledge Base database. Our study revealed that drugs that inhibit non-CYP enzymes are significantly associated with high DILI concern. Particularly, interaction with UDP-glucuronosyltransferases (UGT) enzymes is an important predictor of DILI outcomes. Further analysis indicated that only pure UGT inhibitors and dual substrate inhibitors, but not pure UGT substrates, are significantly associated with high DILI concern. CONCLUSIONS: Drug interactions with UGT enzymes may independently predict DILI, and their combined use with the rule-of-two model further improves overall predictive performance. These findings could expand the currently available tools for assessing the potential for DILI in humans.

2.
Anal Chem ; 96(16): 6218-6227, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38598863

RESUMO

Currently reported aggregation-induced electroluminescence (AIECL) is usually based on the electrostatic integration of luminous monomers, and its application is still limited by the low ECL efficiency and poor structural stability of electrostatic integration-based AIECL emitters. Herein, host-guest recognition-mediated supramolecular AIECL was creatively developed to overcome the defects of electrostatic-integration-based AIECL. Cucurbit[8]uril (CB[8]) as the host recognized tris (2-phenylpyridine) iridium(III) [Ir(ppy)3] as the guest to form a novel supramolecular complex Ir-CB[8]. CB[8] can not only provide a large hydrophobic cavity to efficiently load Ir(ppy)3 and enrich coreactant tripropylamine but also utilize its carbonyl-laced portals to form intramolecular hydrogen bonds to stabilize the supramolecular structure, so Ir-CB[8] revealed excellent AIECL performance. The AIECL emitter Ir-CB[8] coupled the efficient DNA walker to construct a sensing system for miRNA-16 detection. Au nanoparticles@norepinephrine (AuNPs@NE) trapped by single-strand S1 was developed to significantly quench the ECL emission of Ir-CB[8]. When the target microRNA-16 (miRNA-16) existed, H1 was opened and the sequential assembly from H2 to H7 was triggered, forming "windmill"-like DNA walker with six Pb2+-dependent leg DNA. The assembled DNA walker, which was centered on DNA structure, had high efficiency and biocompatibility and can cut S1 to keep the DNA fragment-carrying quencher AuNPs@NE away from the electrode surface, thus restoring the ECL emission of Ir-CB[8] and realizing ultrasensitive detection of miRNA-16. Supramolecular AIECL mediated by host-guest recognition provides a new way for constructing AIECL emitters with excellent structural stability and AIECL efficiency, and an Ir-CB[8] coupling "windmill"-like DNA walker builds a promising ECL-sensing system for bioassay.

3.
Anal Chem ; 96(33): 13644-13651, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39110983

RESUMO

Intracellular detection and imaging of microRNAs (miRNAs) with low expression usually face the problem of unsatisfactory sensitivity. Herein, a novel dual-function DNA nanowire (DDN) with self-feedback amplification and efficient signal transduction was developed for the sensitive detection and intracellular imaging of microRNA-155 (miRNA-155). Target miRNA-155 triggered catalytic hairpin assembly (CHA) to generate plenty of double-stranded DNA (dsDNA), and a trigger primer exposed in dsDNA initiated a hybridization chain reaction (HCR) between four well-designed hairpins to produce DDN, which was encoded with massive target sequences and DNAzyme. On the one hand, target sequences in DDN acted as self-feedback amplifiers to reactivate cascaded CHA and HCR, achieving exponential signal amplification. On the other hand, DNAzyme encoded in DDN acted as signal transducers, successively cleaving Cy5 and BHQ-2 labeled substrate S to obtain a significantly enhanced fluorescence signal. This efficient signal transduction coupling self-feedback amplification greatly improved the detection sensitivity with a limit of detection of 160 aM for miRNA-155, enabling ultrasensitive imaging of low-abundance miRNA-155 in living cells. The constructed DDN creates a promising fluorescence detection and intracellular imaging platform for low-expressed biomarkers, exhibiting tremendous potential in biomedical studies and clinical diagnosis of diseases.


Assuntos
DNA , MicroRNAs , Nanofios , MicroRNAs/análise , MicroRNAs/metabolismo , Nanofios/química , Humanos , DNA/química , DNA Catalítico/química , DNA Catalítico/metabolismo , Transdução de Sinais , Imagem Óptica , Técnicas de Amplificação de Ácido Nucleico , Limite de Detecção
4.
Anal Chem ; 95(26): 10068-10076, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37339328

RESUMO

Improving the electrochemiluminescence (ECL) efficiency of luminophores has always been the goal of the ECL field. Herein, a novel crystallization-induced enhanced ECL (CIE ECL) strategy was exploited to significantly enhance the ECL efficiency of metal complex tris-(8-hydroxyquinoline)aluminum (Alq3). Alq3 monomers self-assembled and directionally grew to form Alq3 microcrystals (Alq3 MCs) in the presence of sodium dodecyl sulfate. The highly ordered crystal structure of Alq3 MCs not only constrained the intramolecular rotation of Alq3 monomers to decrease nonradiative transition but also accelerated the electron transfer between Alq3 MCs and coreactant tripropylamine to increase radiative transition, thus leading to a CIE ECL effect. Alq3 MCs exhibited brilliant anode ECL emission, which was 210-fold stronger than that of Alq3 monomers. The exceptional CIE ECL performance of Alq3 MCs coupled the efficient trans-cleavage activity of CRISPR/Cas12a assisted by rolling circle amplification and catalytic hairpin assembly to fabricate a CRISPR/Cas12a-mediated aptasensor for acetamiprid (ACE) detection. The limit of detection was as low as 0.79 fM. This work not only innovatively exploited a CIE ECL strategy to enhance the ECL efficiency of metal complexes but also integrated CRISPR/Cas12a with a dual amplification strategy for the ultrasensitive monitoring of pesticides such as ACE.

5.
Anal Chem ; 94(23): 8346-8353, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35639506

RESUMO

Currently reported polyfluorene-based fluorescence detection usually shows high background signal and low detection sensitivity. This work developed a novel three-dimensional (3D) DNA rolling walker via directional movement on a lipid bilayer (LB) supported by Au@Fe3O4 nanoparticles (NPs) in a polyfluorene-based fluorescence system so that it could achieve significantly improved detection sensitivity and almost zero-background signal detection for miRNA-16. First, the carboxyl-functionalized poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,1',3}-thiadazole)] polymer nanoparticles (c-PFBT PNPs) covalently bonded with amino-labeled single-strand CP and further hybridized with single-strand AP to prepare AP-CP-coupled c-PFBT PNP probes. Meanwhile, Au@Fe3O4 NPs were developed as efficient fluorescence quenchers and served as the matrix for assembling the LB. The resulting Au@Fe3O4@LB assembled cholesterol-labeled orbital DNA L1 and L2 and further assembled hairpins H1 and AP-CP-coupled c-PFBT PNP probes to construct DNA nanomachines. Then, the target miRNA-16 was introduced to initiate the rolling circle amplification (RCA) reaction and form dynamic DNA rolling walkers, thus releasing single-strand CP-coupled c-PFBT PNP probes. The magnetic separation effect of Au@Fe3O4 NPs made it possible to detect the fluorescence signal from the released probes, thus achieving almost zero-background signal detection for miRNA-16 with a low detection limit of 95 aM. The flexible interfaces provided by the LB endowed the DNA rolling walkers with high binding efficiency and low derailment probability, thus achieving significantly improved detection sensitivity. The developed strategy provided an attractive polyfluorene-based fluorescence platform with high-sensitivity and low-background signals.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Nanopartículas , Técnicas Biossensoriais/métodos , DNA , Limite de Detecção , Bicamadas Lipídicas , Técnicas de Amplificação de Ácido Nucleico/métodos , Andadores
6.
Anal Chem ; 94(10): 4446-4454, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35230820

RESUMO

The enrichment of co-reactants is one of the keys to improving the sensitivity of electrochemiluminescence (ECL) detection. This work developed a novel hydrophobic localized enrichment strategy of co-reactants utilizing the inner hydrophobic cavity of ß-cyclodextrin (ß-CD). Pt nanoparticles (Pt NPs) were grown in situ on the coordination sites for metal ions of ß-CD to prepare the ß-CD-Pt nanocomposite, which could not only enrich co-reactant 3-(dibutylamino) propylamine (TDBA) highly efficiently through its hydrophobic cavity but also immobilize TDBA via the Pt-N bond. Meanwhile, the carboxyl-functionalized poly[2,5-dioctyl-1,4-phenylene] (PDP) polymer nanoparticles (PNPs) were developed as excellent ECL luminophores. With SARS-CoV-2 nucleocapsid protein (ncovNP) as a model protein, the TDBA-ß-CD-Pt nanocomposite combined PDP PNPs to construct a biosensor for ncovNP determination. The PDP PNPs were modified onto the surface of a glassy carbon electrode (GCE) to capture the first antibody (Ab1) and further capture antigen and secondary antibody complexes (TDBA-ß-CD-Pt@Ab2). The resultant biosensor with a sandwich structure achieved a highly sensitive detection of ncovNP with a detection limit of 22 fg/mL. TDBA-ß-CD-Pt shared with an inspiration in hydrophobic localized enrichment of co-reactants for improving the sensitivity of ECL detection. The luminophore PDP PNPs integrated TDBA-ß-CD-Pt to provide a promising and sensitive ECL platform, offering a new method for ncovNP detection.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Humanos , Limite de Detecção , Medições Luminescentes/métodos , Nanopartículas Metálicas/química , Proteínas do Nucleocapsídeo , Polímeros/química , SARS-CoV-2
7.
Anal Chem ; 93(36): 12400-12408, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34469691

RESUMO

The electrochemiluminescence (ECL) ratiometric assay is usually based on two different ECL luminophores, and the choice of two suitable luminophores and shared co-reactant makes its construction challenging. The single-emitter-based ECL ratio mode could overcome the limitation of two luminophores and simplify the construction process, so it is an ideal choice. In this work, CdTe quantum dots (CdTe QDs) were modulated using black phosphorus (BP) nanosheet to simultaneously emit the cathodic and anodic ECL signals, and H2O2 and tripropylamine (TPrA) served as the cathodic and anodic co-reactants, respectively. MicroRNA-126 (miRNA-126) was selected as the template target to exploit the application of BP-CdTe QDs in the single-emitter-based ECL ratio detection. Through the target recycling triggering rolling-circle amplification (RCA) reaction, a large amount of glucose oxidase (GOx)-modified single strand 1 was introduced. GOx catalyzed glucose to produce H2O2 in situ, which acted as a dual-role moderator to quench the anodic ECL emission with TPrA as the co-reactant while enhancing the cathodic emission, thereby realizing the ratiometric detection of miRNA-126 with a low detection limit of 29 aM (S/N = 3). The dual-ECL-emitting BP-CdTe QDs with TPrA-H2O2 as dual co-reactant provide a superior ECL ratio platform involving enzyme catalytic reaction, expanding the application of single-emitter-based ratio sensing in the diverse biological analysis.


Assuntos
Técnicas Biossensoriais , Compostos de Cádmio , MicroRNAs , Pontos Quânticos , Peróxido de Hidrogênio , Fósforo , Telúrio
8.
Anal Chem ; 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34133127

RESUMO

The bifunctional moderator is urgently needed in the field of ratiometric electrochemiluminescence (ECL) sensing since it can mediate simultaneously two ECL signals to conveniently realize their opposite change trend. This work designed a novel dual-signal combined nanoprobe with carboxyl-functionalized poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,1',3}-thiadazole)] nanoparticles (c-PFBT NPs) as the anodic ECL probe and L-cysteine capped CdS quantum dots (L-CdS QDs) as the cathodic ECL probe, which performed a dual-signal output capability without any additional coreactants. More importantly, hydrogen peroxide (H2O2) produced in situ by enzyme-catalyzed reaction was developed as a bifunctional moderator for simultaneously regulating two signals. The dual-signal combined nanoprobe (c-PFBT NPs@CdS QDs) served as the matrix to immobilize acetylcholinesterase (AChE) and choline oxidase for organophosphorus (OPs) analysis. In the absence of OPs, H2O2 was produced by catalyzing the substrate acetylthiocholine (ATCl) with enzymes and it quenched the anodic ECL signal from c-PFBT NPs and simultaneously promoted the cathodic ECL signal from L-CdS QDs. When OPs was present, the activity of AChE was inhibited, the anodic signal would increase, and the cathodic signal would accordingly decrease. The integration of the bifunctional moderator H2O2 and dual-signal combined nanoprobe c-PFBT NPs@CdS QDs not only provides an attractive ECL platform for enzymatic sensing involving the generation or consumption of H2O2 but also paves a new pathway for other ratiometric ECL systems involving enzyme catalytic amplification for detecting antigens, antibodies, DNA, RNA, etc.

9.
J Clin Lab Anal ; 35(8): e23881, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34240756

RESUMO

BACKGROUND: Acute kidney injury (AKI) was characterized by loss of renal function, associated with chronic kidney disease, end-stage renal disease, and length of hospital stay. Long non-coding RNAs (lncRNAs) participated in AKI development and progression. Here, we aimed to investigate the roles and mechanisms of lncRNA MALAT1 in AKI. METHODS: AKI serum samples were obtained from 129 AKI patients. ROC analysis was conducted to confirm the diagnostic value of MALAT1 in differentiating AKI from healthy volunteers. After hypoxic treatment on HK-2 cells, the expressions of inflammatory cytokines, MALAT1, miR-204, APOL1, p65, and p-p65, were measured by RT-qPCR and Western blot assays. The targeted relationship between miR-204 and MALAT1 or miR-204 and APOL1 was determined by luciferase reporter assay and RNA pull-down analysis. After transfection, CCK-8, flow cytometry, and TUNEL staining assays were performed to evaluate the effects of MALAT1 and miR-204 on AKI progression. RESULTS: From the results, lncRNA MALAT1 was strongly elevated in serum samples from AKI patients, with the high sensitivity and specificity concerning differentiating AKI patients from healthy controls. In vitro, we established the AKI cell model after hypoxic treatment. After experiencing hypoxia, we found significantly increased MALAT1, IL-1ß, IL-6, and TNF-α expressions along with decreased miR-204 level. Moreover, the targeted relationship between MALAT1 and miR-204 was confirmed. Silencing of MALAT1 could reverse hypoxia-triggered promotion of HK-2 cell apoptosis. Meanwhile, the increase of IL-1ß, IL-6, and TNF-α after hypoxia treatment could be repressed by MALAT1 knockdown as well. After co-transfection with MALAT1 silencing and miR-204 inhibition, we found that miR-204 could counteract the effects of MALAT1 on HK-2 cell progression and inflammation after under hypoxic conditions. Finally, NF-κB signaling was inactivated while APOL1 expression was increased in HK-2 cells after hypoxia treatment, and lncRNA MALAT1 inhibition reactivated NF-κB signaling while suppressed APOL1 expression by sponging miR-204. CONCLUSIONS: Collectively, these results illustrated that knockdown of lncRNA MALAT1 could ameliorate AKI progression and inflammation by targeting miR-204 through APOL1/NF-κB signaling.


Assuntos
Injúria Renal Aguda/genética , Apolipoproteína L1/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/sangue , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Adulto , Apolipoproteína L1/metabolismo , Estudos de Casos e Controles , Hipóxia Celular/genética , Linhagem Celular , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Testes de Função Renal , Masculino , MicroRNAs/antagonistas & inibidores , Pessoa de Meia-Idade , NF-kappa B/genética , NF-kappa B/metabolismo
10.
Aging (Albany NY) ; 16(13): 10972-10984, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38968594

RESUMO

BACKGROUND: Diabetic nephropathy (DN) is a severe complication of diabetes that affects the kidneys. Disulfidptosis, a newly defined type of programmed cell death, has emerged as a potential area of interest, yet its significance in DN remains unexplored. METHODS: This study utilized single-cell sequencing data GSE131882 from GEO database combined with bulk transcriptome sequencing data GSE30122, GSE30528 and GSE30529 to investigate disulfidptosis in DN. Single-cell sequencing analysis was performed on samples from DN patients and healthy controls, focusing on cell heterogeneity and communication. Weighted gene co-expression network analysis (WGCNA) and gene set enrichment analysis (GSEA) were employed to identify disulfidptosis-related gene sets and pathways. A diagnostic model was constructed using machine learning techniques based on identified genes, and immunocorrelation analysis was conducted to explore the relationship between key genes and immune cells. PCR validation was performed on blood samples from DN patients and healthy controls. RESULTS: The study revealed significant disulfidptosis heterogeneity and cell communication differences in DN. Specific targets related to disulfidptosis were identified, providing insights into the pathogenesis of DN. The diagnostic model demonstrated high accuracy in distinguishing DN from healthy samples across multiple datasets. Immunocorrelation analysis highlighted the complex interactions between immune cells and key disulfidptosis-related genes. PCR validation supported the differential expression of model genes VEGFA, MAGI2, THSD7A and ANKRD28 in DN. CONCLUSION: This research advances our understanding of DN by highlighting the role of disulfidptosis and identifying potential biomarkers for early detection and personalized treatment.


Assuntos
Nefropatias Diabéticas , Análise de Célula Única , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/diagnóstico , Humanos , Análise de Célula Única/métodos , Transcriptoma , Perfilação da Expressão Gênica , Estudos de Casos e Controles , Redes Reguladoras de Genes , Aprendizado de Máquina
11.
Food Chem ; 457: 140100, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38901352

RESUMO

Chloramphenicol (CAP) poses a threat to human health due to its toxicity and bioaccumulation, and it is very important to measure it accurately and sensitively. This work explored a host-guest recognition strategy to mediate dual aggregation-induced electrochemiluminescence (AIECL) of 1,1,2,2-tetrakis(4-(pyridin-4-yl) phenyl)-ethene (TPPE) for ratio detection of CAP, in which, cucurbit[8]uril (CB[8]) served as host to assemble guest TPPE. The resulting supramolecular complex CB[8]-TPPE exhibited excellent dual-AIECL-emission with signal strength approximately four times that of TPPE aggregates and black hole quencher-1 (BHQ1) could efficiently quench dual-AIECL signal. CB[8]-TPPE coupled dual-function quencher BHQ1 and high-efficiency DNA reactor to achieve ultra-sensitive detection of CAP, exhibiting a linearity range of 10 fmol·L-1-100 nmol·L-1 and limit of detection of 1.81 fmol·L-1. CB[8]-TPPE provides a novel way to improve the dual-emission of TPE derivatives and sets up a promising platform for CAP detection, demonstrating a good practical application potential.


Assuntos
Cloranfenicol , Técnicas Eletroquímicas , Medições Luminescentes , Cloranfenicol/análise , Cloranfenicol/química , Técnicas Eletroquímicas/instrumentação , Medições Luminescentes/instrumentação , Medições Luminescentes/métodos , Limite de Detecção , Antibacterianos/química , Antibacterianos/análise , Contaminação de Alimentos/análise , Hidrocarbonetos Aromáticos com Pontes/química , Luminescência , Imidazóis/química , Compostos Heterocíclicos com 2 Anéis , Compostos Macrocíclicos , Imidazolidinas
12.
Lupus Sci Med ; 11(1)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38351097

RESUMO

OBJECTIVE: The efficacy of sirolimus in treating severe or refractory systemic lupus erythematosus (SLE) has been confirmed by small-scale clinical trials. However, few studies focused on mild or moderate SLE. Therefore, in this study we elucidated clinical efficacy of add-on sirolimus in patients with mild or moderate SLE. METHODS: Data of 17 consecutive patients with SLE were retrospectively collected. SLE Disease Activity Index-2000 (SLEDAI-2K), clinical manifestation, laboratory data and peripheral T lymphocyte subsets with cytokines were collected before and 6 months after sirolimus add-on treatment. T cell subsets were detected by flow cytometry and cytokines were determined by multiplex bead-based flow fluorescent immunoassay simultaneously. Twenty healthy controls matched with age and sex were also included in our study. RESULTS: (1) The numbers of peripheral blood lymphocytes, T cells, T helper (Th) cells, regulatory T (Treg) cells, Th1 cells, Th2 cells and Treg/Th17 ratios in patients with SLE were significantly lower, while the numbers of Th17 cells were evidently higher than those of healthy control (p<0.05). (2) After 6 months of sirolimus add-on treatment, urinary protein, pancytopenia, immunological indicators and SLEDAI-2K in patients with SLE were distinctively improved compared with those before sirolimus treatment (p<0.05). (3) The numbers of peripheral blood lymphocytes, T cells, Th cells, Treg cells, Th2 cells and the ratios of Treg/Th17 in patients with SLE after treatment were clearly higher than those before (p<0.05). (4) The levels of plasma interleukin (IL)-5, IL-6 and IL-10 in patients with SLE decreased notably, conversely the IL-4 levels increased remarkably compared with pretreatment (p<0.05). CONCLUSIONS: (1) Patients with SLE presented imbalanced T cell subsets, especially the decreased ratio of Treg/Th17. (2) Sirolimus add-on treatment ameliorated clinical involvement, serological abnormalities and disease activity without adverse reactions in patients with SLE. (3) The multi-target therapy facilitates the enhanced numbers of Treg cells, Treg/Th17 imbalance and anti-inflammatory cytokines, simultaneously, reducing inflammatory cytokines.


Assuntos
Lúpus Eritematoso Sistêmico , Sirolimo , Humanos , Sirolimo/efeitos adversos , Estudos Retrospectivos , Subpopulações de Linfócitos T/metabolismo , Citocinas
13.
Adv Mater ; 36(27): e2403958, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38641326

RESUMO

Spinel oxides with tunable chemical compositions have emerged as versatile electrocatalysts, however their performance is greatly limited by small surface area and low electron conductivity. Here, ultrathin high-entropy Fe-based spinel oxides nanosheets are rationally designed (i.e., (Co0.2Ni0.2Zn0.2Mg0.2Cu0.2)Fe2O4; denotes A5Fe2O4) in thickness of ≈4.3 nm with large surface area and highly exposed active sites via a modified sol-gel method. Theoretic and experimental results confirm that the bandgap of A5Fe2O4 nanosheets is significantly smaller than that of ordinary Fe-based spinel oxides, realizing the transformation of binary spinel oxide from semiconductors to metalloids. As a result, such A5Fe2O4 nanosheets manifest excellent performance for the nitrate reduction reaction (NO3 -RR) to ammonia (NH3), with a NH3 yield rate of ≈2.1 mmol h-1 cm-2 at -0.5 V versus Reversible hydrogen electrode, outperforming other spinel-based electrocatalysts. Systematic mechanism investigations reveal that the NO3 -RR is mainly occurred on Fe sites, and introducing high-entropy compositions in tetrahedral sites regulates the adsorption strength of N and O-related intermediates on Fe for boosting the NO3 -RR. The above findings offer a high-entropy platform to regulate the bandgap and enhance the electrocatalytic performance of spinel oxides.

14.
Biosens Bioelectron ; 237: 115539, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37487285

RESUMO

Constructing mono-luminophor-based electrochemiluminescence (ECL) ratio system is a great challenge due to the limitations of the luminescent species with dual-signal-output, luminescence efficiency and coreactant. This work developed carboxyl-functionalized poly[9,9-bis(3'-(N,N-dimethylamino) propyl)-2,7-fluorene]-alt-2,7-(9,9 dioctylfluorene)] nanoparticles(PFN NPs) as dual-emitting luminophors, which can synchronously output strong cathodic and anodic ECL signals without any exogenous coreactants. The inherent molecular structure enabled efficient intramolecular electron transfer between tertiary amine groups and backbone of PFN to generate strong cathodic and anodic ECL emission. Particularly, H+ in aqueous solution played an irreplaceable role for cathodic ECL emission. The silver nanoparticles (AgNPs) were developed as signal regulator because of their excellent hydrogen evolution reaction (HER) activity, which significantly quenched the cathodic signal while kept the anodic signal unchanged. The dual-emitting PFN NPs cleverly integrated signal regulator AgNPs and bicyclic strand displacement amplification (SDA) to construct a coreactant-free mono-luminophor-based ratiometric ECL sensing for SARS-CoV-2 RdRp gene assay. The strong dual-emitting of PFN NPs and excellent quenching effect of AgNPs on cathodic emission endowed the biosensor with a high detection sensitivity, and the detection limit was as low as 39 aM for RdRp gene. The unique dual-emitting properties of PFN NPs open up a new path to construct coreactant-free mono-luminophor-based ECL ratio platform, and excellent HER activity of AgNPs offers some new thoughts for realizing ECL signal changes.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanopartículas Metálicas , Humanos , Polímeros/química , Nanopartículas Metálicas/química , SARS-CoV-2/genética , Medições Luminescentes , COVID-19/diagnóstico , Prata , RNA Polimerase Dependente de RNA , Técnicas Eletroquímicas
15.
Molecules ; 17(8): 9469-75, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22874791

RESUMO

Inhibition of UDP-glucuronosyltransferase (UGT) isoforms can result in severe clinical results, including clinical drug-drug interactions (DDI) and metabolic disorders of endogenous substances. The present study aims to investigate the inhibition of demethylzeylasteral (an important active component isolated from Tripterygium wilfordii Hook F.) towards three important UGT isoforms UGT1A6, UGT1A9 and UGT2B7. The results showed that 100 µM of demethylzeylasteral exhibited strong inhibition towards UGT1A6 and UGT2B7, with negligible influence towards UGT1A9. Furthermore, Dixon and Lineweaver-Burk plots showed the inhibition of UGT1A6 and UGT2B7 by demethylzeylasteral was best fit to competitive inhibition, and the inhibition kinetic parameters (Ki) were calculated to be 0.6 µM and 17.3 µM for UGT1A6 and UGT2B7, respectively. This kind of inhibitory effect need much attention when demethylzeylasteral and demethylzeyasteral-containing herbs (e.g., Tripterygium wilfordii Hook F.) were co-administered with the drugs mainly undergoing UGT1A6, UGT2B7-catalyzed metabolism. However, when extrapolating the in vivo clinical results using our present in vitro data, many complex factors might affect final results, including the contribution of UGT1A6 and UGT2B7 to the metabolism of compounds, and the herbal or patients' factors affecting the in vivo concentration of demethylzeylasteral.


Assuntos
Inibidores Enzimáticos/química , Glucuronosiltransferase/antagonistas & inibidores , Triterpenos/química , Glucuronosiltransferase/química , Humanos , Himecromona/análogos & derivados , Himecromona/química , Cinética , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/química , UDP-Glucuronosiltransferase 1A
16.
Biosens Bioelectron ; 212: 114420, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35635968

RESUMO

The limitation of the selection of dual-emitting luminophor and dual-function moderator makes the construction of single-luminophor-based electrochemiluminescence (ECL) ratio strategy extremely challenging. This work developed black phosphorus nanosheet loaded with CdTe quantum dots (BP-CdTe QDs) as dual-emitting luminophor, and TiO2 nanosheets (NSs) as dual-function moderator to construct single-luminophor-based ECL ratio biosensor for amyloid-ß protein (Aß) detection. The BP-CdTe QDs modified glassy carbon electrode (GCE) firstly captured the anti-Aß1, and then the target Aß. Finally, the secondary antibody composites containing N,N-diethylethylenediamine (DEDA) and TiO2 NSs were captured on the electrode surface. DEDA in the secondary antibody composites and S2O82- added in the detection solution served as the anodic and cathodic co-reactants, respectively, and TiO2 NSs as co-reaction accelerator can simultaneously enhance two emissions. The increase of target concentration made the two signals show different increasing trend, thus achieving a sensitive ratio detection of target Aß with the detection limit of 21 fg/mL. The dual-emitting BP-CdTe QDs coupled with dual-function moderator TiO2 NSs provide an attractive single-luminophor-based ECL ratio platform for bioassay, which can not only be applied to the detection of Aß, but also to the detection of other disease biomarkers.


Assuntos
Técnicas Biossensoriais , Compostos de Cádmio , Pontos Quânticos , Bioensaio , Técnicas Eletroquímicas , Medições Luminescentes , Telúrio , Titânio
17.
J Hazard Mater ; 432: 128699, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35325864

RESUMO

In general, suitable double luminophores and their coreactants are necessary for constructing electrochemiluminescence (ECL) ratio strategy. However, the complexity of matching double luminophores and the stability and repeatability problem suffered by introducing exogenous coreactant would greatly limit the application of ratio detection. An original single-luminophore-based ECL ratio sensing was developed excluding any exogenous coreactants in this work. The poly [9,9-bis(3'-(N,N-dimethylamino)propyl)- 2,7-fluorene]-alt-2,7-(9,9-dioctylfluorene)] nanoparticles (PFN NPs) were explored to emit two anodic ECL signals. One centered at + 1.25 V (ECL-1) with the scanning potential of 0 ~ + 1.25 V and the other at + 1.95 V (ECL-2) with the scanning potential of 0 ~ + 1.95 V. ECL-1 showed a very strong emission without any exogenous coreactant. Importantly, hydrogen peroxide (H2O2) was able to efficiently weaken ECL-1 but strengthen ECL-2. When organophosphorus pesticides (OPs) were absent, the immobilized acetylcholinesterase-choline oxidase (AChE-ChOx) would catalyze the substrate acetylthiocholine chloride (ATCl) to produce H2O2, resulting in a quenched ECL-1 and an enhanced ECL-2. With the introduction of OPs, ECL-1 increased while ECL-2 accordingly decreased as OPs prohibited production of H2O2 by inhibiting activity of AChE. Highly sensitive ECL ratio detection for OPs was realized based on the change of the ratio of two signals. The dual anode emission properties of PFN NPs coupled with the opposite regulation of H2O2 on the two signals paved a new avenue for potentially tunable ECL ratio sensing strategy, and showed enormous potential applications for OPs analysis.


Assuntos
Técnicas Biossensoriais , Nanopartículas , Praguicidas , Acetilcolinesterase , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Peróxido de Hidrogênio/química , Medições Luminescentes/métodos , Nanopartículas/química , Compostos Organofosforados , Praguicidas/análise , Polímeros/química
18.
Biosens Bioelectron ; 218: 114786, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36223701

RESUMO

SnS2 quantum dots (QDs) as excellent electrochemiluminescence (ECL) luminators have exhibited a good application prospect in ECL field, but the difficulty of being effectively immobilized on the electrode and inner filter effect caused by their compact packaging make the construction of SnS2 QDs-based ECL system challenging. This work developed a hollow polymeric spherical nanoshells (HPSNs) for loading SnS2 QDs. SiO2 nanoparticles (NPs) served as the carrier for the multilayer assembly of polyethyleneimine (PEI)-SnS2 QDs and polyacrylic acid (PAA). Then, SiO2 NPs were etched to produce SnS2 QDs-based HPSNs (SnS2-HPSNs), which can not only achieve the high loading of SnS2 QDs but effectively reduce their inner filter effect, revealing a significantly improved cathodic ECL performance. SnS2-HPSNs coupled with anodic luminators Ir nanorods (NRs) to construct a ratiometric ECL biosensor for detecting cardiac troponin I (cTnI) with tripropylamine (TPrA) and persulfate (S2O82-) as anodic and cathodic co-reactants, respectively. Norepinephrine (NE) and gold nanoparticles (AuNPs) were innovatively developed as dual-quencher for Ir NRs. The secondary antibody complex containing SnS2-HPSNs and NE-AuNPs was specially constructed and its assembly on the biosensor modified with Ir NRs can conveniently realize the different changes of the two signals, thus achieving the sensitive detection of cTnI with a detection limit of 0.32 pg/mL. The HPSNs provided an effective strategy for high loading of QDs while reducing their inner filter effect. The integration of two luminators (SnS2-HPSNs and Ir NRs) and dual-quencher created a promising ECL ratio platform for the accurate detection of various biomarkers.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanoconchas , Pontos Quânticos , Ouro , Técnicas Biossensoriais/métodos , Medições Luminescentes/métodos , Troponina I , Polietilenoimina , Dióxido de Silício , Bioensaio , Norepinefrina , Técnicas Eletroquímicas
19.
Biosens Bioelectron ; 216: 114629, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36001932

RESUMO

Iridium(III) complexes have been developed as eminent electrochemiluminescence (ECL) luminophores, but their current applications are only limited to anodic ECL emission because of weak cathodic ECL emission. This work explored poly(styrene-co-maleicanhydride) (PSMA) as functional reagent to modulate iridium(III) complexes to simultaneously emit bipolar ECL signals. The prepared iridium(III) nanorods (Ir NRs) were detected strong bipolar ECL emissions at +0.9 V and -2.0 V with N,N-diisopropylethylenediamine (DPEA) and persulfate (S2O82-) as coreactant, respectively. Meanwhile, Ag nanoparticles (Ag NPs) were developed as dual-regulating coreaction accelerator to boost the bipolar emissions of Ir NRs simultaneously. The dual-emitting Ir NRs coupled with dual-regulating coreaction accelerator Ag NPs facilitated the construction of mono-luminophore-based ECL ratio strategy for detecting amyloid-ß oligomers (AßO). When the target AßO appeared, the Mg2+-dependent DNAzyme-powered biped walkers were unlocked to cleave single-stranded S1 immobilized on the surface of magnetic beads (MBs), resulting in the production of massive single-stranded ST. Then, the output ST cleaved hairpin H1 captured by Ir NRs modified electrode to produce numerous single strands, which could initiate the hybridization chain reaction (HCR) between Ag NPs-labeled H2 and Ag NPs-labeled H3 to introduce abundant Ag NPs onto the electrode surface. Due to the enhancement effect of Ag NPs on the bipolar ECL emissions from Ir NRs, the ECL ratio detection of AßO was achieved with the detection limit of 0.62 pM. The unique dual-emitting properties of Ir NRs coupled with dual-regulating effect of Ag NPs provided an interesting mono-luminophore-based ECL ratio sensing platform for biological analysis.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Nanopartículas Metálicas , Nanotubos , Peptídeos beta-Amiloides , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Irídio , Limite de Detecção , Medições Luminescentes/métodos , Prata , Estirenos
20.
ACS Appl Mater Interfaces ; 13(27): 32013-32021, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34212714

RESUMO

The reported donor donor-acceptor ("DD-A") fluorescence resonance energy transfer (FRET) was typically achieved through random collisions and interactions of DNA molecules in the bulk solution, which has inevitable defects, including weak biological stability, slow reaction kinetics, and low hybridization efficiency. In order to overcome these deficiencies, this work developed a quadrivalent cruciform DNA nanostructure (qCDN)-mediated cascaded catalyzed hairpin assembly (CHA) amplifier for the fluorescence detection of amyloid ß oligomer species (AßOs). First, four H1 and four H2 hairpins were assembled on one qCDN to obtain qCDNH1 and qCDNH2, respectively. In the presence of AßOs, strand C was released from the P1-C hybrid hairpin and then alternately opened qCDNH1 and qCDNH2 to trigger the qCDN-mediated CHA. As a result, double donors in H1 and one acceptor in H2 were mutually closed, and the porous DNA nanonet with a high loading of "DD-A" FRET binary probes was formed. The FRET efficiency was approximately 78%, and the initial reaction rate was 25-fold faster than the conventional CHA. The detection limit of AßOs was as low as 0.69 pM. The combination of the "DD-A" FRET binary probes and qCDN-mediated cascaded amplifier exhibited great promise for detecting biomarkers with trace levels.


Assuntos
Peptídeos beta-Amiloides/química , DNA Cruciforme/química , Transferência Ressonante de Energia de Fluorescência/métodos , Limite de Detecção , Nanoestruturas/química , Multimerização Proteica , Estrutura Quaternária de Proteína
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