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Precise and reliable monitoring of DNA adenine methyltransferase (Dam) activity is essential for disease diagnosis and biological analysis. However, existing techniques for detecting Dam activity often rely on specific DNA recognition probes that are susceptible to DNA degradation and exhibit limited target sensitivity and specificity. In this study, we designed and engineered a stable and dynamic DNA nanodevice called the double-loop interlocked DNA circuit (DOOR) that enables the sensitive and selective monitoring of Dam activity in complex biological environments. The DOOR incorporates two interlocked specialized sequences: a palindromic sequence for Dam identification and an initiator sequence for signal amplification. In the presence of Dam, the DOOR is cleaved by double-stranded DNA phosphodiesterase I endonuclease, generating massive double-stranded DNA (dsDNA) units. These units can self-assemble into a long dsDNA scaffold, thereby enhancing the subsequent reaction kinetics. The dsDNA scaffold further triggers a hyperbranched hybrid chain reaction to produce a fluorescent 3D DNA nanonet, enabling more precise monitoring of the Dam activity. The DOOR device exhibits excellent sensitivity, specificity, and stability, rendering it a powerful tool for studying DNA methylation in various biological processes and diseases.
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Life molecules' distributions in live systems construct the complex dynamic reaction networks, whereas it is still challenging to demonstrate the dynamic distributions of biomolecules in live systems. Herein, we proposed a dynamic analysis strategy via sequence-structure bispecific RNA with state-adjustable molecules to monitor the dynamic concentration and spatiotemporal localization of these biomolecules in live cells based on the new insight of fluorescent RNA (FLRNA) interactions and their mechanism of fluorescence enhancement. Typically, computer-based nucleic acid-molecular docking simulation and molecular theoretical calculation have been proposed to provide a simple and straightforward method for guiding the custom-design of FLRNA. Impressively, a novel FLRNA with sequence and structure bispecific RNA named as a structure-switching aptamer (SSA) was introduced to monitor the real-time concentration and spatiotemporal localization of biomolecules, contributing to a deeper insight of the dynamic monitoring and visualization of biomolecules in live systems.
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Corantes Fluorescentes , RNA , RNA/química , Simulação de Acoplamento Molecular , Corantes Fluorescentes/químicaRESUMO
MicroRNAs (miRNAs) in tumor-derived extracellular vesicles (tEVs) are important cancer biomarkers for cancer screening and early diagnosis. Multiplex detection of miRNAs in tEVs facilitates accurate diagnosis but remains a challenge. Herein, we propose an encoded fusion strategy to profile the miRNA signature in tEVs for pancreatic cancer diagnosis. A panel of encoded-targeted-fusion beads was fabricated for the selective recognition and fusion of tEVs, with the turn-on fluorescence signals of molecule beacons for miRNA quantification and barcode signals for miRNA identification using readily accessible flow cytometers. Using this strategy, six types of pancreatic-cancer-associated miRNAs can be profiled in tEVs from 2 µL plasma samples (n = 36) in an isolation-free and lysis-free manner with only 2 h of processing, offering a high accuracy (98%) to discriminate pancreatic cancer, pancreatitis, and healthy donors. This encoded fusion strategy exhibits great potential for multiplex profiling of miRNA in tEVs, offering new avenues for cancer diagnosis and screening.
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Vesículas Extracelulares , MicroRNAs , Neoplasias Pancreáticas , Humanos , MicroRNAs/genética , Vesículas Extracelulares/genética , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , Neoplasias PancreáticasRESUMO
BACKGROUND: The previous epidemiological and experimental evidence has implied the linkage between chronic inflammation to idiopathic pulmonary fibrosis (IPF). However, it was still unclear whether there were casual associations between circulating inflammatory cytokines and IPF development. The objective of present study was to examine whether altered genetically predicted concentration of circulating cytokines were associated with IPF development using a two-sample Mendelian randomization (MR) analysis. MATERIALS AND METHODS: The causal effects of 23 circulating inflammatory cytokines were evaluated on IPF using MR analysis. The primary approach of MR analysis was the inverse variance-weighted (IVW) method. The sensitivity analyses were conducted by simple median, weighted median, penalized weighted median and MR-Egger regression methods. RESULTS: The present MR study found suggestive evidence that a higher circulating IL-14 level was associated with an increased risk of IPF (random effects IVW method: odds ratio: 1.001, 95% confidence interval: 1.000-1.001, P = 0.026). The sensitivity analysis yielded directionally similar results for IL-14. There was no significant association found between other circulating inflammatory cytokines and IPF. CONCLUSION: The high level of IL14 predicted by genes had a casual relationship with the increased risk of IPF. This finding provided epidemiological evidence for drug therapy targeting inflammatory factors in the prevention and treatment of IPF. It's warranted further exploration to validate the clinical significance of IL14 associated with developmental risk of IPF.
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Fibrose Pulmonar Idiopática , Análise da Randomização Mendeliana , Humanos , Fibrose Pulmonar Idiopática/genética , Inflamação/genética , Relevância Clínica , Citocinas/genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The protein phenotypes of extracellular vesicles (EVs) have emerged as promising biomarkers for cancer diagnosis and treatment monitoring. However, the technical challenges in rapid isolation and multiplexed molecular detection of EVs have limited their clinical practice. Herein, we developed a magnetically driven tandem chip to achieve streamlined rapid isolation and multiplexed profiling of surface protein biomarkers of EVs. Driven by magnetic force, the magnetic nanomixers not only act as tiny stir bars to promote mass transfer and enhance reaction efficiency of EVs, but also transport on communicating vessels of the tandem chip continuously and expedite the assay workflow. We designed cyclic surface enhancement of Raman scattering (SERS) tags to bind with target EVs and then release them by exonuclease I, eliminating steric hindrance and amplifying the SERS signal of multiple protein biomarkers on EVs. Due to the excellent assay performance, six breast cancer biomarkers were detected simultaneously on EVs using only 10â µL plasma within 1.5â h. The unweighted SUM signature offers great accuracy in discriminating breast cancer patients from healthy donors. Overall, the dynamic magnetic driving tandem chip offers a new avenue to advance the clinical application of EV-based liquid biopsy.
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Neoplasias da Mama , Vesículas Extracelulares , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Biomarcadores Tumorais/metabolismo , Vesículas Extracelulares/metabolismo , FenótipoRESUMO
Herein, 10-fold electrochemiluminescence (ECL) enhancement from a porous SnO2 nanocrystal (SnO2 NC) xerogel (vs discrete SnO2 NCs) was first observed with NO3- as a novel coreactant. This new booster phenomenon caused by pore characteristic was defined as "pore confinement-induced ECL enhancement", which originated from two possible reasons: First, the SnO2 NC xerogel with hierarchically porous structure could not only localize massive luminophore near the electrode surface, more importantly, but could accelerate the electrochemical and chemiluminescence reaction efficiency because the pore channels of xerogel could promote the mass transport and electron transfer in the confined spaces. Second, the NO3- could be in situ reduced easily to the active nitrogen species by means of the pore confinement effect, which could be served as a new coreactant for nanocrystal-based ECL amplification with the excellent stability and good biocompatibility. As a proof of concept, a facile and sensitive sensing platform for SO32- detection has been successfully constructed upon effectively quenching of SO32- toward the SnO2 NC xerogel/NO3- ECL system. The key feature about this work presented a grand avenue to achieve the strong ECL signal, especially from weak emitters, which gave a fresh impetus to the construction of new-generation of surface-confined ECL platform with potential applications in ECL imaging and sensing.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Nanopartículas/química , Nitratos/química , Sulfitos/análise , Compostos de Estanho/química , Ácido 3-Mercaptopropiônico/química , Géis/químicaRESUMO
Copper nanoclusters (Cu NCs) as emerging luminescent metal NCs are gaining increasing attention owing to the comparatively low cost and high abundance of the Cu element in nature. However, it remains challenging to manipulate the optical properties of Cu NCs. Unlike most dispersed Cu NCs, whose luminescence efficiency was restricted by nonexcited relaxation, the Cu NCs confined in a porous poly-l-cysteine (poly-l-Cys) film were generated controllably with enhanced electrochemiluminescence (ECL) by in situ electrochemical reduction. Specifically, poly-l-Cys provided a porous structure to regulate the generation of Cu NCs within its holes, which not only increased the restriction on the intramolecular vibration and rotation of the ligands but also expedited the electron transfer near the electrode surface, reflecting in an enhancement of the ECL signal and efficiency. As an application of the confined Cu NCs, an ECL biosensor with high performance was constructed skillfully for highly sensitive detection of alkaline phosphatase (ALP), which adopted Cu NCs as the ECL luminophore and poly-l-Cys as a coreaction accelerator in a novel ECL ternary system (Cu NCs/S2O82-/poly-l-Cys). Furthermore, an ingenious target amplification based on the combination of a DNA walker and click chemistry was developed to convert ALP to DNA strands efficiently, achieving great improvement in the recognition efficiency. As a result, the biosensor had a low detection limit (9.5 × 10-7 U·L-1) and a wide linear range (10-8-10-2 U·L-1) for ALP detection, which showed great promise for the detection of non-nucleic acid targets and the diagnosis of diseases.
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Fosfatase Alcalina/sangue , Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Nanopartículas Metálicas/química , Peptídeos/química , Fosfatase Alcalina/metabolismo , Cobre/química , Humanos , Tamanho da Partícula , Porosidade , Propriedades de SuperfícieRESUMO
Perylene and its derivatives, as classical organic polycyclic aromatic hydrocarbon (PAH) ECL materials, have attracted extensive attention due to their excellent photoelectric activity and good structural controllability. As is well-known, the molecular structure of perylene is composed of five coplanar aromatic rings. There are intense π-π stacking interactions between perylene molecules, which lead to their aggregation and poor solubility in aqueous media. Unfortunately, this aggregation can weaken or even quench the emission intensity of perylene owing to the aggregation-caused quenching (ACQ) effect, finally limiting the analytical application of perylene in biological detection. In this work, perylene composite microcrystals (ETTA@Pe MCs) doped with non-planar molecular tetrakis(4-aminophenyl)ethene were synthesized in the aqueous phase by a surfactant-assisted self-assembly method. During this process, the intense π-π stacking interactions between perylene monomers were suppressed by doping. As a result, the ETTA@Pe MCs exhibited a significantly enhanced ECL signal as compared to that of perylene microcrystals (Pe MCs) in the presence of S2O82- as a co-reactant. Moreover, the ETTA@Pe MCs were utilized as a novel electrochemiluminescent (ECL) luminophores to fabricate a sensitive ECL biosensor for the quantitative analysis of dopamine (DA), which displayed a favorable linear response from 1 to 100 µmol L-1 with a detection limit of 0.96 nmol L-1.
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Técnicas Biossensoriais , Perileno , Técnicas Eletroquímicas , Etilenos , Medições LuminescentesRESUMO
Herein, we designed an electrochemiluminescence (ECL) biosensor with SnS2 quantum dots (SnS2 QDs) as novel emitters for the ultrasensitive assay of cytomegalovirus pp65 antibody (anti-CMV pp65) via smart circular peptide-DNA nanomachine amplification. First, the novel ECL biosensing platform was constructed by self-assembly of water-soluble, nontoxic, and earth-abundant SnS2 QDs on the 3D hierarchical silver nanoflowers (Ag NFs) surface, where the Ag NFs, as coreaction accelerator in the ECL ternary (SnS2 QDs/S2O82-/Ag NFs) system, could efficiently boost the ECL intensity of SnS2 QDs. Furthermore, we designed a specific nucleic acid sequence labeled antigenic peptide to act as multifunctionalized capture probe (CP), which could specifically recognize the target antibody assisting with two auxiliary DNA strands via the proximity hybridization of DNA motifs to form a smart circular peptide-DNA nanomachine. Then, with the aid of nuclease, the resultant circular peptide-DNA nanomachine could initiate the subsequent cascade recycling amplification to output massive DNA products as mimic target (MT). As a result, the proposed ECL biosensor for anti-CMV pp65 detection exhibited high sensitivity with a wide linear range from 1 fM to 100 nM and a low detection limit (0.33 fM). Importantly, this work not only first utilized SnS2 QDs as promising ECL emitters for biosensing platform construction but also opened an efficient way for highly sensitive and selective detection of antibody in disease diagnosis and clinical analysis.
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Anticorpos Antivirais/análise , Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Pontos Quânticos/química , Sulfetos/química , Compostos de Estanho/química , Anticorpos Antivirais/imunologia , Citomegalovirus/imunologia , Humanos , Luminescência , Tamanho da Partícula , Sulfetos/síntese química , Propriedades de Superfície , Compostos de Estanho/síntese químicaRESUMO
In this work, with the use of Ag(I) ion as robust coreaction accelerator for the enhancement of 3,4,9,10-perylenetetracarboxylic acid-peroxydisulfate (PTCA-S2O82-) system, a highly sensitive solid-state electrochemiluminescence (ECL)-biosensing platform was successfully designed for the detection of mercury ions (Hg2+). Specifically, a long guanine-rich (C-rich) double-stranded DNA (dsDNA) was generated by the target-Hg2+-controlled DNA machine that could amplify the ECL signal of the PTCA-S2O82- system by embedding the Ag(I) ion. Herein, the Ag(I) ion, as a coreaction accelerator, could first react with S2O82- to produce Ag(II) ion and a sulfate radical anion (SO4·-). Then, the accompanying Ag(II) ion could react with H2O to generate the reactive intermediate species (i.e., hydroxyl radical (OH·)), which could further accelerate the reduction of S2O82- to output more SO4·-. Moreover, the recycling of the Ag(I) ion and Ag(II) ion was easily achieved by the electrochemical reaction. Therefore, an avalanche-type reaction was triggered to generate massive amounts of SO4·-, which could react with the luminophore (PTCA) to achieve an extremely strong ECL signal. The ECL mechanism was investigated by ECL and cycle voltammetry (CV) and by the analysis of the fluorescence (FL), ECL, and electron-paramagnetic-resonance (EPR) spectra. As a result, the proposed solid-state ECL-biosensing platform for Hg2+ detection exhibited high sensitivity, with a linear range from 1 × 10-15 to 1 × 10-10 M and a detection limit of 3.3 × 10-16 M. Importantly, this work was the first to utilize a metal ion as a coreaction accelerator and provided a promising approach to improve the sensitivity of target analyses in ECL-biosensing fields.
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Técnicas Eletroquímicas , Luminescência , Mercúrio/análise , Perileno/análogos & derivados , Prata/química , Sulfatos/química , Íons/química , Tamanho da Partícula , Perileno/química , Propriedades de SuperfícieRESUMO
The development of a sensitive and practical electrochemiluminescence (ECL) bioassay relies on the use of ECL signal tags whose signal intensity is high and stable. In this work, strong ECL emission was achieved from metal organic framework (MOF) accelerator enriched quantum dots (CdTe), which were applied as an efficient ECL signal tag for trace biomarker detection. It is particularly noteworthy that a novel mechanism to drastically enhance the ECL intensity of CdTe is established because isoreticular metal organic framework-3 (IRMOF-3) with 2-amino terephthalic acid (2-NH2-BDC) as the organic ligand not only allows for loading a large amount of CdTe via the encapsulating effect and internal/external decoration but also functions as a novel coreactant accelerator for promoting the conversion of coreactant S2O82- into the sulfate radical anion (SO4â¢-), further boosting the ECL emission of CdTe. On the basis of the simple sandwich immunoreaction approach, cardiac troponin-I antigen (cTnI), a kind of biomarker related with myocardial infarction, was chosen as a detection model using an IRMOF-3-enriched CdTe labeled antibody as the signal probe. This immunosensor demonstrated desirable assay performance for cTnI with a wide response range from 1.1 fg mL-1 to 11 ng mL-1 and a very low detection limit (0.46 fg mL-1). This suggested that the IRMOF-3-enriched CdTe nanocomposite strategy can integrate the coreactant accelerator and luminophore to significantly enhance the ECL intensity and stability, providing a direction for promising ECL tag preparation with broad applications.
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Electrochemiluminescence (ECL) has attracted much attention in various fields of analysis owing to low background signals, high sensitivity, and excellent controllability. In recent years, to further boost the performance of biosensors, diverse output signal modes have been developed, which exhibited respective advantages. In this review, we summarize the latest sensing applications of ECL bioanalysis by generalizing different output signal modes and give future perspectives for new developments in ECL analytical technology.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições LuminescentesRESUMO
In this work, an "on-off-on" switch system has been successfully applied through the construction of an electrochemiluminscent biosensor for copper ion (Cu(2+) ) detection based on a new electrochemiluminescence (ECL) emitter of supramolecular nanorods, which was achieved through supramolecular interactions between 3,4,9,10-perylenetetracarboxylic acid (PTCA) and aniline. The initial "signal-on" state with strong and stable ECL emission was obtained by use of the supramolecular nanorods with a new signal amplification strategy involving a co-reaction accelerator. In addition, ECL quencher probes (Fc-NH2 /Cu-Sub/nano-Au) were fabricated by immobilizing aminoferrocene (Fc-NH2 ) on Cu-substrate strand modified Au nanoparticles. The quencher probes were hybridized with the immobilized Cu-enzyme strand to form Cu(2+) -specific DNAzyme. Similarly, the "signal-off" state was obtained by the high quenching effect of Fc-NH2 on the ECL of the excited-state PTCA ((1) PTCA*). As expected, the second "switch-on" state could achieved by incubating with the target Cu(2+) , owing to the Cu(2+) -specific DNAzyme, which was irreversibly cleaved, resulting in the release of the quencher probes from the sensor interface. Herein, on the basis of the ECL intensity changes (ΔIECL ) before and after incubating with the target Cu(2+) , the prepared Cu(2+) -specific DNAzyme-based biosensor was used for the determination of Cu(2+) concentrations with high sensitivity, excellent selectivity, and good regeneration.
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In this paper, a novel electrochemiluminescence resonance energy transfer (ECL-RET) system from O2/S2O8(2-) to a kind of amino-terminated perylene derivative (PTC-NH2) was demonstrated for the first time, which was then applied to construct a ratiometric aptasensor for lead ion (Pb(2+)) detection. First, gold-nanoparticles-functionalized fullerene nanocomposites (AuNPs@nano-C60) were coated on a glassy carbon electrode (GCE), and then thiol-modified assistant probes (APs) were attached on AuNPs@nano-C60/GCE. Then the resultant electrode was hybridized with capture probes (the aptamer of the Pb(2+), abbreviated as CPs) to generate DNA duplexes, which could induce PTC-NH2 to be intercalated into the dsDNA grooves by the electrostatic adsorption. Herein, ECL dual peaks at -0.7 V (vs Ag/AgCl) and -2.0 V (vs Ag/AgCl) were obtained when the prepared aptasensor was detected in air-saturated S2O8(2-) solution, which could be attributed to the emission of excited dimmers (π-excimers) ((1)(NH2-PTC)2*) and (1)(O2)2*, respectively. In the presence of Pb(2+), the dsDNA was unwound, and Pb(2+) G-quadruplex structure was generated because of the highly specific affinity between Pb(2+) and CPs, which made the PTC-NH2 release from the electrode surface. As a result, the ECL signal at -0.7 V was decreased, and the ECL signal around -2.0 V was increased. By measuring the ratio of ECL intensities at two excitation potentials, the developed aptasensor exhibited the linear response range from 1.0 × 10(-12) M to 1.0 × 10(-7) M with a detection limit of 3.5 × 10(-13) M (S/N = 3) for Pb(2+), which could offer an alternative analytical method with excellent properties of high selectivity, accuracy, and sensitivity.
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Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas , Chumbo/análise , Ouro/química , Íons/análise , Medições Luminescentes , Nanopartículas Metálicas/química , Solo/químicaRESUMO
Here we report for the first time the phenomenon of continuously color-tunable electrochemiluminescence (ECL) from individual gold nanoclusters (Au NCs) confined in a porous hydrogel matrix by adjusting the concentration of the co-reactant. Specifically, the hydrogel-confined Au NCs exhibit strong dual-color ECL in an aqueous solution with triethylamine (TEA) as a co-reactant, with a record-breaking quantum yield of 95%. Unlike previously reported Au NCs, the ECL origin of the hydrogel-confined Au NCs is related to both the Au(0) kernel and the Au(i)-S surface. Surprisingly, the surface-related ECL of Au NCs exhibits a wide color-tunable range of 625-829 nm, but the core-related ECL remains constant at 489 nm. Theoretical and experimental studies demonstrate that the color-tunable ECL is caused by the dynamic surface reconstruction of Au NCs and TEA radicals. This work opens up new avenues for dynamically manipulating the ECL spectra of core-shell emitters in biosensing and imaging research.
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The clinical potential of miRNA-based liquid biopsy has been largely limited by the heterogeneous sources in plasma and tedious assay processes. Here, we develop a precise and robust one-pot assay called dual-surface-protein-guided orthogonal recognition of tumor-derived exosomes and in situ profiling of microRNAs (SORTER) to detect tumor-derived exosomal miRNAs and enhance the diagnostic accuracy of prostate cancer (PCa). The SORTER uses two allosteric aptamers against exosomal marker CD63 and tumor marker EpCAM to create an orthogonal labeling barcode and achieve selective sorting of tumor-specific exosome subtypes. Furthermore, the labeled barcode on tumor-derived exosomes initiated targeted membrane fusion with liposome probes to import miRNA detection reagents, enabling in situ sensitive profiling of tumor-derived exosomal miRNAs. With a signature of six miRNAs, SORTER differentiated PCa and benign prostatic hyperplasia with an accuracy of 100%. Notably, the diagnostic accuracy reached 90.6% in the classification of metastatic and nonmetastatic PCa. We envision that the SORTER will promote the clinical adaptability of miRNA-based liquid biopsy.
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Exossomos , MicroRNAs , Neoplasias da Próstata , Masculino , Humanos , Exossomos/genética , Proteínas de Membrana , MicroRNAs/genética , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Biomarcadores Tumorais/genéticaRESUMO
Background: Aspergillus fumigatus is an opportunistic fungal pathogen, which is commonly found in lungs and rarely causes infections in mediastinum. Mediastinal Aspergillus abscess is a serious infectious condition, and is characterized by difficult diagnosis due to its clinical manifestations being nonspecific. Case Presentation: Here, we report a case of a mediastinal Aspergillus fumigatus abscess in an immunocompetent patient. The patient was a 45-year-old woman who presented with a 20-day history of sore throat without any underlying diseases. Chest computed tomography (CT) showed a mass in the anterior superior mediastinum. Metagenomic next-generation sequencing (mNGS) identified Aspergillus fumigatus sequences in endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) tissue, indicating the mediastinal Aspergillus fumigatus infection of this patient. The following mediastinal biopsy histological analysis and tissue fungi culture also suggested Aspergillus fumigatus infection, confirming the mNGS detection. The patient was diagnosed with mediastinal aspergillosis caused by Aspergillus fumigatus. After timely voriconazole treatment, the patient was discharged with good condition. Conclusion: Our study presented a rare case with mediastinal Aspergillus fumigatus abscess in an immunocompetent patient. As a new clinical diagnostic method, mNGS could assist timely diagnosis and precise treatment of Aspergillus infection.
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Recently, ternary electrochemiluminescence (ECL) system has become a hot research topic due to its great potential for improving ECL efficiency by promoting the generation of intermediates. However, it is still a great challenge to increase the utilization rate of intermediates in a ternary ECL system. Herein, we propose a strategy to increase the utilization rate of intermediates by designing pyrenecarboxaldehyde (Pyc) encapsulated porous titania (pTiO2) nanospheres (Pyc@pTiO2) as ECL nanoreactors for an integrated ternary (luminophore/coreactant/co-reaction accelerator, Pyc/S2O82-/TiO2) ECL system construction. Specifically, pTiO2 acted as an ECL co-reaction accelerator, in which Pyc could obtain electrons from the conduction band of TiO2 to produce more SO4Ë-, increasing its emissions. Simultaneously, pTiO2 could provide confined reaction spaces to effectively shorten the diffusion distance, extend the lifetime of free radicals, increase the utilization rate of intermediates and improve the efficiency of the ternary ECL system. As a proof of concept, the Pyc@pTiO2 nanoreactors-based sensing platform was successfully constructed to sensitively monitor cellular GSH levels. Overall, this work for the first time proposed an avenue to increase the utilization rate of intermediates in a ternary ECL system, which opened a new route for ECL biosensing in cell analysis applications.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Nanotecnologia , Porosidade , TitânioRESUMO
Anti-infection strategies against pleural empyema include the use of antibiotics and drainage treatments, but bacterial eradication rates remain low. A major challenge is the formation of biofilms in the pleural cavity. DNase has antibiofilm efficacy in vitro, and intrapleural therapy with DNase is recommended to treat pleural empyema, but the relevant mechanisms remain limited. Our aim was to investigate whether DNase I inhibit the early biofilm formation in Pseudomonas aeruginosa- or Staphylococcus aureus-induced empyema models. We used various assays, such as crystal violet staining, confocal laser scanning microscopy (CLSM) analysis, peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH), and scanning electron microscopy (SEM) analysis. Our results suggested that DNase I significantly inhibited early biofilm formation in a dose-dependent manner, without affecting the growth of P. aeruginosa or S. aureus in vitro. CLSM analysis confirmed that DNase I decreased the biomass and thickness of both bacterial biofilms. The PNA-FISH and SEM analyses also revealed that DNase I inhibited early (24h) biofilm formation in two empyema models. Thus, the results indicated that DNase inhibited early (24h) biofilm formation in P. aeruginosa- or S. aureus-induced rabbit empyema models and showed its therapeutic potential against empyema biofilms.
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Empiema Pleural , Infecções Estafilocócicas , Animais , Coelhos , Pseudomonas aeruginosa , Staphylococcus aureus , Desoxirribonucleases/farmacologia , Hibridização in Situ Fluorescente , Infecções Estafilocócicas/tratamento farmacológico , Biofilmes , Antibacterianos/uso terapêutico , Desoxirribonuclease I/farmacologiaRESUMO
Liquid biopsy offers non-invasive and real-time molecular profiling of individual patients, and is thus considered a revolutionary technology in precision medicine. Exosomes have been acknowledged as significant biomarkers in liquid biopsy, as they play a central role in cell-cell communication and are closely related to the pathogenesis of most human malignancies. Nevertheless, in biofluids exosomes always co-exist with other particles, and the cargo components of exosomes are highly heterogeneous. Thus, the isolation and molecular characterization of exosomes are still technically challenging. Microfluidics technology effectively addresses this challenge by virtue of its inherent advantages, such as precise manipulation of fluids, low consumption of samples and reagents, and a high level of integration. Recent advances in microfluidics allow in situ exosome capture and molecular detection with unprecedented selectivity and sensitivity. In this review, the state-of-the-art developments in microfluidics-based exosome research, including exosome isolation approaches and molecular detection strategies, with highlights of the characterization of exosomal biomarkers in cancer liquid biopsy is summarized. The major challenges are also discussed and some perspectives for the future directions of exosome-based liquid biopsy in microfluidic systems are presented.