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Exploring the high-performance photoelectronic properties of perovskite quantum dots (QDs) is desirable for paper-based photoelectrochemical (PEC) sensing;however, challenges remain in improving their stability and fundamental performance. Herein, a novel Z-scheme heterostructure with host-guest interaction by the confinement of CH3NH3PbBr3 QDs within Cu3(BTC)2 metal-organic framework (MOF) crystal (MAPbBr3@Cu3(BTC)2) is successfully constructed on the paper-based PEC device for ultrasensitive detection of Ochratoxin A (OTA), with the assistance of the exciton-plasmon interaction (EPI) effect. The host-guest interaction is estabilished by encapsulating MAPbBr3 QDs as guests within Cu3(BTC)2 MOF as a host, which prevents MAPbBr3 QDs from being damaged in the polar system, offering access to long-term stability with high-performance PEC properties. Benefiting from the precise alignment of energy levels, the photogenerated charge carriers can migrate according to the Z-scheme charge-transfer pathway under the driving force of the internal electric field, achieving a high photoelectric conversion efficiency. Upon OTA recognition, the EPI effect is activated to modulate the exciton response in MAPbBr3 QDs by accelerating radiative decay, finally achieving sensitive OTA sensing with a detection limit of 0.017 pg mL-1. We believe this work renders new insight into designing host-guest Z-scheme heterojunctions in constructing the paper-based PEC sensing platforms for environmental monitoring.
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Efficient carrier separation is vitally crucial to improving the detection sensitivity of photoelectrochemical (PEC) biosensors. Here, we developed a facile strategy to efficiently regulate the carrier separation efficiency of the photoactive matrix BiOI and In2S3 signal label functionalized paper chip by manipulation of electrons spin-state and rational design of electron transport pathways. The spin-dependent electronic structures of BiOI and In2S3 were regulated via enhanced electron-spin parallel alignment induced by an external magnetic field, markedly retarding carrier recombination and extending their lifetime. Simultaneously, with the progress of the target-induced catalytic hairpin assembly process, the transfer path of photogenerated carriers was changed, leading to a switch in photocurrent polarity from cathode to anode. This reversed electron transport pathway not only boosted the separation ability of photogenerated electrons but also eliminated false-positive and false-negative signals, thereby further improving the detection sensitivity. As a proof of concept, the well-designed magnetic field-stimulated paper-based PEC biosensor showed highly selectivity and sensitivity for acetamiprid assay with a wide linear range of 1 fM to 20 nM and an ultralow detection limit of 0.73 fM. This work develops a universal strategy for improving the sensitivity of biosensors and exhibits enormous potential in the fields of bioanalysis and clinical diagnosis.
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MicroRNA (miRNA) detection is a critical aspect of disease diagnosis, and recent studies indicate that miRNA-622 could be a potential target for lung cancer. Herein, Cu single atoms were anchored on graphitic carbon nitride (Cu SAs@CN) as a coreaction accelerator applied in luminol-H2O2 system, thereby establishing an efficient and sensitive electrochemiluminescence (ECL) biosensor for miRNA-622 detection. Cu SAs@CN was explored to possess excellent enzyme-like activities that promote the generation of abundant reactive oxygen species, which amplified ECL emission. Meanwhile, in order to improve the accuracy and sensitivity for miRNA-622 detection, the highly specific trans-cleavage ability of CRISPR/Cas12a was combined with a catalytic hairpin assembly strategy. Therefore, an ECL biosensor for miRNA-622 detection was systematically constructed as a proof of concept, achieving an ultralow limit of detection of 1.09 fM, and the feasibility was demonstrated in human serum samples. The findings of this research provide a promising strategy to enhance the ECL response using versatile single-atom catalysts, thus advancing the development of ECL biosensing applications.
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Técnicas Biossensoriais , Cobre , Técnicas Eletroquímicas , Grafite , Medições Luminescentes , Luminol , MicroRNAs , Técnicas Biossensoriais/métodos , Humanos , MicroRNAs/análise , MicroRNAs/sangue , Cobre/química , Grafite/química , Luminol/química , Limite de Detecção , Peróxido de Hidrogênio/química , Compostos de Nitrogênio/química , Catálise , Proteínas Associadas a CRISPR , Sistemas CRISPR-Cas , Proteínas de Bactérias , EndodesoxirribonucleasesRESUMO
Designing photocatalysts with efficient charge transport and abundant active sites for photocatalytic CO2 reduction in pure water is considered a potential approach. Herein, a nickel-phthalocyanine containing Ni-N4 active sites-based conjugated microporous polymer (NiPc-CMP), offering highly dispersed metal active sites, satisfactory CO2 adsorption capability, and excellent light harvesting properties, is engineered as a photocatalyst. By virtue of the covalently bonded bridge, an atomic-scale interface between the NiPc-CMP/Bi2 WO6 Z-scheme heterojunction with strong chemical interactions is obtained. The interface creates directional charge transport highways and retains a high redox potential, thereby enhancing the photoexcited charge carrier separation and photocatalytic efficiency. Consequently, the optimal NiPc-CMP/Bi2 WO6 (NCB-3) achieves efficient photocatalytic CO2 reduction performance in pure water under visible-light irradiation without any sacrificial agent or photosensitizer, affording a CO generation rate of 325.9 µmol g-1 with CO selectivity of 93% in 8 h, outperforming those of Bi2 WO6 and NiPc-CMP, individually. Experimental and theoretical calculations reveal the promotion of interfacial photoinduced electron separation and the role of Ni-N4 active sites in photocatalytic reactions. This study presents a high-performance CMP-based Z-scheme heterojunction with an effective interfacial charge-transfer route and rich metal active sites for photocatalytic CO2 conversion.
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IMPORTANCE: Coxsackievirus A6 (CV-A6) is a major emerging pathogen associated with atypical hand, foot, and mouth disease and can cause serious complications such as encephalitis, acute flaccid paralysis, and neurorespiratory syndrome. Therefore, revealing the associated pathogenic mechanisms could benefit the control of CV-A6 infections. In this study, we demonstrate that the nonstructural 2CCV-A6 suppresses IFN-ß production, which supports CV-A6 infection. This is achieved by depleting RNA sensors such as melanoma differentiation-associated gene 5 and retinoic acid-inducible gene I (RIG-I) through the lysosomal pathway. Such a function is shared by 2CEV-A71 and 2CCV-B3 but not 2CCV-A16, suggesting the latter might have an alternative way to promote viral replication. This study broadens our understanding of enterovirus 2C protein regulation of the RIG-I-like receptor signaling pathway and reveals a novel mechanism by which CV-A6 and other enteroviruses evade the host innate immune response. These findings on 2C may provide new therapeutic targets for the development of effective inhibitors against CV-A6 and other enterovirus infections.
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Infecções por Coxsackievirus , Humanos , Enterovirus Humano A/genética , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/virologia , Doença de Mão, Pé e Boca/virologia , Imunidade Inata , Infecções por Coxsackievirus/metabolismo , Infecções por Coxsackievirus/virologia , Interferon beta/metabolismoRESUMO
LN005 is a peptide-drug conjugate (PDC) targeting glucose-regulated protein 78 (GRP78) to treat several types of cancer, such as breast, colon, and prostate cancer.As a new drug modality, understanding its metabolism and elimination pathways will help us to have a whole picture of it. Currently, there are no metabolic studies on LN005; therefore, this study aimed to investigate the metabolism of LN005, clarify its metabolic profile in the liver S9s of different species, and identify the major metabolic pathways and differences between species.The incubation samples were measured by ultra-high performance liquid chromatography combined with orbitrap tandem mass spectrometry (UHPLC-Orbitrap-HRMS).The results showed that LN005 was metabolised by liver S9s, and four metabolites were identified. The main metabolic pathway of LN005 in liver S9s was oxidative deamination to ketone or hydrolysis. Similar metabolic profiles were observed in mouse, rat, dog, monkey, and human liver S9s, indicating no differences between these four animal species and humans.This study provides information for the structural modification and optimisation of LN005 and affords a reference for subsequent animal experiments and human metabolism of other PDCs.
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Fígado , Microssomos Hepáticos , Masculino , Ratos , Camundongos , Humanos , Animais , Cães , Microssomos Hepáticos/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Peptídeos/metabolismo , HaplorrinosRESUMO
Pulsed lasers alter the optical properties of semiconductors and affect the photoelectric function of the photodetectors significantly, resulting in transient changes known as bleaching. Bleaching has a profound impact on the control and interference of photodetector applications. Experiments using pump-probe techniques have made significant contributions to understanding ultrafast carrier dynamics. However, there are few theoretical studies to the best of our knowledge. Here, carrier dynamic models for semiconductors and photodetectors are established, respectively, employing the rectified carrier drift-diffusion model. The pulsed laser bleaching effect on seven types of semiconductors and photodetectors from visible to long-wave infrared is demonstrated. Additionally, a continuous bleaching method is provided, and the finite-difference time-domain (FDTD) method is used to solve carrier dynamic theory models. Laser parameters for continuous bleaching of semiconductors and photodetectors are calculated. The proposed bleaching model and achieved laser parameters for continuous bleaching are essential for several applications using semiconductor devices, such as infrared detection, biological imaging, and sensing.
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Herein, a newly designed two-in-one tetrahedral DNA (TDN) nanostructure with an antifouling surface and backbone-rigidified interfacial tracks was developed for highly sensitive and selective detection of miRNA-182-5p. The well-regulated TDN tracks were assembled onto the surface of the TiO2/MIL-125-NH2-functionalized paper electrode, which efficiently avoided the obstacle of DNA strand tangling and decreased the probability of suspension during the walking process, thus greatly promoting the moving efficiency of DNA walkers. More interestingly, the TDN-modified sensing interfaces demonstrated incomparable antifouling ability against protein samples and interfering miRNAs due to the strong hydrophilic capacity and special molecular conformations, which addressed the dilemma of low sensitivity from traditional antifouling coating strategies. As a proof of concept, the designed bifunctional tetrahedron-modified paper-based photoelectrochemical sensor was successfully used to quantify miRNA-182-5p with a low detection limit of 0.09 fM and high specificity and was validated for monitoring of miRNA-182-5p in real samples. This TDN-engineered biointerface could be used as a universal platform for tracking various targets by substituting the biorecognition events, providing great promise for bioanalysis and clinical diagnosis.
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Incrustação Biológica , Técnicas Biossensoriais , MicroRNAs , Nanoestruturas , Incrustação Biológica/prevenção & controle , DNA/química , MicroRNAs/análise , Nanoestruturas/química , Técnicas Eletroquímicas , Limite de DetecçãoRESUMO
Novel high-performance fluorescent approaches have always significant demand for room-temperature detection of carbon monoxide (CO), which is highly toxic even at low concentration levels and is not easy to recognize due to its colorless and odorless nature. In this paper, we constructed a palladium-mediated fluorescence turn-on sensing platform (TPANN-Pd) for the recognition of CO at room temperature, revealing simultaneously quick response speed (<30 s), excellent selectivity, superior sensitivity, and low detection limit (â¼160 nM for CORM-3, â¼1.7 ppb for CO vapor). Moreover, rapid detection and efficient removal (24%) from the air by naked-eye vision has been successfully realized based on TPANN-Pd supramolecular gels. Furthermore, the developed sensing platform was elucidated with low cytotoxicity and high cellular uptake, and it was successfully applied to CO imaging in living cells, providing real-time monitoring of potential CO-involved reactions in biological systems.
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Monóxido de Carbono , Paládio , Corantes Fluorescentes/química , Corantes Fluorescentes/toxicidadeRESUMO
Near-infrared (NIR)-responsive bioassays based on upconversion nanoparticle (UCNP) incorporating high-performance semiconductors have been developed by researchers, but most lack satisfactory ultrasensitivity for exceedingly trace amounts of target. Herein, for the first time, the CRISPR/Cas13a system is combined with cascade DNA circuits, fluorescent resonance energy transfer (FRET) effect, and luminescence-confined UCNPs-bonded CuInS2/ZnO p-n heterostructures-functionalized paper-working electrode to construct dual-signal-on paper-supported NIR-irradiated photoelectrochemical (PEC) (NIR-PEC) and upconversion luminescence (UCL) bioassay for high-sensitive quantification of miRNA-106a (miR-106a). By constructing an ideal FAM-labeled aminating molecular beacon (FAM-H2) model, a relatively good FRET ratio between the UCNP and FAM (≈85.3%) can be achieved. In the existence of miR-106a, the hairpin-structure FAM-H2 was unwound, bringing about the distance increase of UCNP and FAM and the restraint of FRET. Accordingly, both the NIR-PEC signal and the UCL intensity gradually recovered distinctly. Unlike conventional single-mode PEC sensors, with NIR excitation, the designed dual-mode sensing system could implement minimized misdiagnose assay and quantitative miR-106a determination with low detection limits, that is, 76.54 and 51.36 aM for NIR-PEC and UCL detection, respectively. This work not only broadens the horizon of application of the CRISPR/Cas13a strategy toward biosensing but also constructs a new structure of the UCNP-semiconductor in the exploration of efficient NIR-responsive tools and inspires the construction of a no-misdiagnosed and novel biosensor for dual-mode liquid biopsy.
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Técnicas Biossensoriais , MicroRNAs , Nanopartículas , Transferência Ressonante de Energia de Fluorescência , Luminescência , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Nanopartículas/química , DNA , BioensaioRESUMO
Nitric oxide (NO), as a critical transcellular messenger, participates in a variety of physiological and pathological processes. However, its real-time detection still faces challenges due to its short half-life and trace amounts. Here, MWCNTs@COF-366-Co was prepared by in situ growth of a cobalt porphyrin-based covalent organic framework (COF-366-Co) on multi-walled carbon nanotubes (MWCNTs), and a unique biosensing platform for ultrasensitive real-time NO determination was established. Remarkably, MWCNTs@COF-366-Co contains plenty of atomically arranged M-N4 active sites for electrocatalysis, which provides more efficient electron transfer pathways and resolves the random arrangement issue of active sites. COF-366-Co with a high surface area contains a large number of exposed active M-N4 sites, providing faster NO transport/diffusion and more efficient electron transfer pathways. Due to the synergy of atomic-level periodic structural features of COF-366-Co and high conductivity of MWCNTs, the MWCNTs@COF-366-Co electrochemical biosensor exhibited excellent NO determination performance in a wide range from 0.09 to 400 µM, with high sensitivity (8.9 µA µM-1 cm-2) and a low limit of detection (16 nM). Moreover, the biosensor has been successfully used to sensitively monitor NO molecules released from human umbilical vein endothelial cells (HUVECs). This research not only designed a multifunctional intelligent biosensor platform, but also provided a broad prospect for continuous dynamic monitoring of the activity of living cells and their released metabolites.
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Técnicas Biossensoriais , Estruturas Metalorgânicas , Nanotubos de Carbono , Porfirinas , Humanos , Nanotubos de Carbono/química , Estruturas Metalorgânicas/química , Óxido Nítrico , Porfirinas/química , Células Endoteliais da Veia Umbilical Humana , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Limite de DetecçãoRESUMO
TPN171 is a novel phosphodiesterase-5 (PDE5) inhibitor used to treat pulmonary arterial hypertension (PAH) and erectile dysfunction (ED), which currently is undergoing phase II clinical trials in China. In this single-center, single-dose, nonrandomized, and open design study, radiolabeled [14C]TPN171 was used to investigate the metabolic mechanism, pharmacokinetic characteristics, and clearance pathways of TPN171 in 6 healthy Chinese male volunteers. Each volunteer was administered a single oral suspension of 10 mg (100 µCi) of [14C]TPN171. We found that TPN171 was absorbed rapidly in humans with a peak time (Tmax) of 0.667 h and a half-life (t1/2) of approximately 9.89 h in plasma. Excretion of radiopharmaceutical-related components was collected 216 h after administration, accounting for 95.21% of the dose (46.61% in urine and 48.60% in feces). TPN171 underwent extensive metabolism in humans. Twenty-two metabolites were detected in human plasma, urine, and feces using a radioactive detector combined with a high-resolution mass spectrometer. According to radiochromatograms, a glucuronide metabolite of O-dealkylated TPN171 exceeded 10% of the total drug-related components in human plasma. However, according to the Food and Drug Administration (FDA) guidelines, no further tests are needed to evaluate the safety of this metabolite because it is a phase II metabolite, but the compound is still worthy of attention. The main metabolic biotransformation of TPN171 was mono-oxidation (hydroxylation and N-oxidation), dehydrogenation, N-dealkylation, O-dealkylation, amide hydrolysis, glucuronidation, and acetylation. Cytochrome P450 3A4 (CYP3A4) mainly catalyzed the formation of metabolites, and CYP2E1 and CYP2D6 were involved in the oxidative metabolism of TPN171 to a lesser extent. According to the incubation data, M1 was mainly metabolized to M1G by UDP-glucuronosyltransferase 1A9 (UGT1A9), followed by UGT1A7 and UGT1A10.
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Inibidores da Fosfodiesterase 5 , Hipertensão Arterial Pulmonar , Humanos , Masculino , Inibidores da Fosfodiesterase 5/uso terapêutico , Pirimidinonas , Biotransformação , Fezes , Administração OralRESUMO
We recently showed that site-specific incorporation of 2'-modifications or neutral linkages in the oligo-deoxynucleotide gap region of toxic phosphorothioate (PS) gapmer ASOs can enhance therapeutic index and safety. In this manuscript, we determined if introducing substitution at the 5'-position of deoxynucleotide monomers in the gap can also enhance therapeutic index. Introducing R- or S-configured 5'-Me DNA at positions 3 and 4 in the oligodeoxynucleotide gap enhanced the therapeutic profile of the modified ASOs suggesting a different positional preference as compared to the 2'-OMe gap modification strategy. The generality of these observations was demonstrated by evaluating R-5'-Me and R-5'-Ethyl DNA modifications in multiple ASOs targeting HDAC2, FXI and Dynamin2 mRNA in the liver. The current work adds to a growing body of evidence that small structural changes can modulate the therapeutic properties of PS ASOs and ushers a new era of chemical optimization with a focus on enhancing the therapeutic profile as opposed to nuclease stability, RNA-affinity and pharmacokinetic properties. The 5'-methyl DNA modified ASOs exhibited excellent safety and antisense activity in mice highlighting the therapeutic potential of this class of nucleic acid analogs for next generation ASO designs.
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DNA/química , Oligonucleotídeos Antissenso/química , Animais , Glucose/análogos & derivados , Glucose/química , Células HeLa , Humanos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Oligonucleotídeos Antissenso/uso terapêutico , Oligonucleotídeos Antissenso/toxicidade , Compostos Organofosforados/síntese química , Ribonuclease HRESUMO
The human blood protein vitronectin (Vn) is a major component of the abnormal deposits associated with age-related macular degeneration, Alzheimer's disease, and many other age-related disorders. Its accumulation with lipids and hydroxyapatite (HAP) has been demonstrated, but the precise mechanism for deposit formation remains unknown. Using a combination of solution and solid-state NMR experiments, cosedimentation assays, differential scanning fluorimetry (DSF), and binding energy calculations, we demonstrate that Vn is capable of binding both soluble ionic calcium and crystalline HAP, with high affinity and chemical specificity. Calcium ions bind preferentially at an external site, at the top of the hemopexin-like (HX) domain, with a group of four Asp carboxylate groups. The same external site is also implicated in HAP binding. Moreover, Vn acquires thermal stability upon association with either calcium ions or crystalline HAP. The data point to a mechanism whereby Vn plays an active role in orchestrating calcified deposit formation. They provide a platform for understanding the pathogenesis of macular degeneration and other related degenerative disorders, and the normal functions of Vn, especially those related to bone resorption.
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Cálcio/metabolismo , Durapatita/metabolismo , Degeneração Macular/metabolismo , Vitronectina/metabolismo , Sítios de Ligação , Cálcio/química , Durapatita/química , Humanos , Ligação Proteica , Vitronectina/químicaRESUMO
In this study, transglutaminase (TG), glucono-δ-lactone (GDL), and citric acid (CA) were used to induce the formation of whey protein isolate (WPI)-milk fat emulsion gels to embed lutein, and the emulsion gels induced in different ways were used for the preparation of processed cheese. The protective effect of emulsion gels induced in different ways on lutein was investigated, and the stability of lutein in emulsion gels and processed cheese was analyzed. The results showed that the acidification rate of CA was higher than that of GDL, which was the key step in acid-induced gels, and that the difference in acidification rate led to differences in gel structure. Compared with the 2 acid inducers (GDL and CA), TG exhibited greater potential for forming gel structures with high strength. The TG-induced emulsion gels showed the best physical stability and the highest embedding efficiency for lutein. After heat treatment (85°C), the GDL-induced emulsion gels had higher retention rate of lutein and showed good thermal stability compared with the CA-induced emulsion gels. The processed cheese added with the TG-induced emulsion gel had higher hardness and springiness compared with the processed cheese added with the other 2 kinds of emulsion gels, whereas the processed cheese added with the CA-induced emulsion gel had a lower density of network structure, showing porosity and a larger aggregated structure, but the highest bioavailability of lutein. These results provide valuable information for the formation of cold-set emulsion gel and provide the possibility for the application of emulsion gel embedding active substances in processed cheese.
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Queijo , Leite , Animais , Leite/química , Proteínas do Soro do Leite/análise , Luteína/análise , Emulsões , Transglutaminases , Géis/químicaRESUMO
Brown fermented milk (BFM) is favored by consumers in the dairy market for its unique burnt flavor and brown color. However, Maillard reaction products (MRP) from high-temperature baking are also noteworthy. In this study, tea polyphenols (TP) were initially developed as potential inhibitors of MRP formation in BFM. The results showed that the flavor profile of BFM did not change after adding 0.08% (wt/wt) of TP, and its inhibition rates on 5-hydroxymethyl-2-furaldehyde (5-HMF), glyoxal (GO), methylglyoxal (MGO), Nε-carboxymethyl lysine (CML), and Nε-carboxyethyl lysine (CEL) were 60.8%, 27.12%, 23.44%, 57.7%, and 31.28%, respectively. After 21 d of storage, the levels of 5-HMF, GO, MGO, CML, and CEL in BFM with TP were 46.3%, 9.7%, 20.6%, 5.2%, and 24.7% lower than the control group, respectively. Moreover, a smaller change occurred in their color and the browning index was lower than that of the control group. The significance of this study was to develop TP as additives to inhibit the production of MRP in brown fermented yogurt without changing color and flavors, thereby making dairy products safer for consumers.
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Reação de Maillard , Leite , Animais , Leite/química , Lisina/análise , Polifenóis/análise , Óxido de Magnésio , Aldeído Pirúvico/análise , Glioxal/análise , Produtos Finais de Glicação Avançada/análise , CháRESUMO
A DNA triangular prism nanomachine (TPN)-based logic device for intracellular AND-gated imaging of adenosine triphosphate (ATP) has been constructed. By using i-motif sequences and ATP-binding aptamers as logic control units, the TPN logic device is qualified to respond to the acidic environment and ATP in cancer cell lysosomes. Once internalized into the lysosome, the specific acidic microenvironment in lysosome causes the i-motif sequence to fold into a tetramer, resulting in compression of DNA tri-prism. Subsequently, the split ATP aptamer located at the tip of the collapsed triangular prism binds stably to ATP, which results in the fluorescent dyes (Cy3 and Cy5) modified at the ends of the split aptamer being in close proximity to each other, allowing Förster Resonance Energy Transfer (FRET) to occur. The FRET signals are excited at a wavelength of 543 nm and can be collected within the emission range of 646-730 nm. This enables the precise imaging of ATP within a cell. We also dynamically operate AND logic gates in living cells by modulating intracellular pH and ATP levels with the help of external drugs. Owing to the AND logic unit on TPN it can simultaneously recognize two targets and give corresponding intelligent logic judgment via imaging signal output. The accuracy of molecular diagnosis of cancer can be improved thus eliminating the false positive signal of single target-based detection. Hence, this space-controlled TPN-based logical sensing platform greatly avoids sensitivity to extracellular targets during the cell entry process, providing a useful tool for high-precision imaging of the cancer cell's endogenous target ATP.
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Trifosfato de Adenosina , Aptâmeros de Nucleotídeos , Trifosfato de Adenosina/química , Aptâmeros de Nucleotídeos/química , DNA/química , Diagnóstico por Imagem , Transferência Ressonante de Energia de FluorescênciaRESUMO
Exosomal microRNAs (miRNAs) as newly emerging reliable and noninvasive biomarkers have demonstrated a significant function in early cancer diagnosis. Photoelectrochemical (PEC) biosensing has attracted unprecedented attention in exosomal miRNA monitoring due to its inherent advantages of both electrochemical and optical techniques; however, the severe charge carrier recombination greatly restricts the PEC assay performance. Herein, a high-sensitive PEC strategy assisted by the piezoelectric effect is designed based on Bi2WO6/Cu2S heterojunctions and implemented for the monitoring of exosomal miRNAs. The introduction of the piezoelectric effect enables promoted electron-hole transfer and separation, thereby improving the analytical sensitivity. In addition, a target reprogramming metal-organic framework-capped CaO2 (MOF@CaO2) hybrids is prepared, in which MOF@CaO2 being responsive to exosomal miRNAs induces exposure of the capped CaO2 to H2O and then triggers self-supplying of H2O2, which effectively suppresses the electron-hole recombination, giving rise to an amplified photocurrent and a decrease in the cost of the reaction. Benefiting from the coupled sensitization strategy, the as-fabricated PEC strategy exhibits high sensitivity, specificity, low cost, and ease of use for real-time analysis of exosomal miRNAs within the effectiveness linear range of 0.1 fM-1 µM. The present work demonstrates promising external field coupling-enhanced PEC bioassay and offers innovative thoughts for applying this strategy in other fields.
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Técnicas Biossensoriais , Estruturas Metalorgânicas , MicroRNAs , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Elétrons , Peróxido de Hidrogênio , Limite de Detecção , MicroRNAs/análiseRESUMO
MicroRNAs extracted from exosomes (exosomal miRNAs) have recently emerged as promising biomarkers for early prognosis and diagnosis. Thus, the development of an effective approach for exosomal miRNA monitoring has triggered extensive attention. Herein, a sensitive photoelectrochemical (PEC) biosensing platform is demonstrated for exosomal miRNA assay via the target miRNA-powered λ-exonuclease for the amplification strategy. The metal-organic framework (MOF)-decorated WO3 nanoflakes heterostructure is constructed and implemented as the photoelectrode. Also, a target exosomal miRNA-activatable programmed release nanocarrier was fabricated, which is responsible for signal control. Hemin that acted as the electron acceptor was prior entrapped into the programmed control release nanocarriers. Once the target exosomal miRNAs-21 was introduced, the as-prepared programmed release nanocarriers were initiated to trigger the release of hemin, which enabled the quenching of the photocurrent. Under the optimized conditions, the level of exosomal miRNAs-21 could be accurately tracked ranging from 1 fM to 0.1 µM with a low detection limit of 0.5 fM. The discoveries illustrate the possibility for the rapid and efficient diagnosis and prognosis prediction of diseases based on the detection of exosomal miRNAs-21 and would provide feasible approaches for the fabrication of an efficient platform for clinical applications.
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Técnicas Biossensoriais , Exossomos , MicroRNAs , Exossomos/química , Hemina/análise , MicroRNAs/análise , PrognósticoRESUMO
This work proposed a novel double-engine powered paper photoelectrochemical (PEC) biosensor based on an anode-cathode cooperative amplification strategy and various signal enhancement mechanisms, which realized the monitoring of multiple miRNAs (such as miRNA-141 and miRNA-21). Specifically, C3N4 quantum dots (QDs) sensitized ZnO nanostars and BiOI nanospheres simultaneously to construct a composite photoelectric layer that amplified the original photocurrent of the photoanode and photocathode, respectively. Through the independent design and partition of a flexible paper chip to functionalize injection holes and electrode areas, the bipolar combination completed the secondary upgrade of signals, which also provided biological reaction sites for multitarget detection. With the synergistic participation of a three-dimensional (3D) DNA nanomachine and programmable CRISPR/Cas12a shearing tool, C3N4 QDs lost their attachment away from the electrode surface to quench the signal. Moreover, electrode zoning significantly reduced the spatial cross talk of related substances for multitarget detection, while the universal trans-cleavage capability of CRISPR/Cas12a simplified the operation. The designed PEC biosensor revealed excellent linear ranges for detection of miRNA-141 and miRNA-21, for which the detection limits were 5.5 and 3.4 fM, respectively. With prominent selectivity and sensitivity, the platform established an effective approach for trace multitarget monitoring in clinical applications, and its numerous pioneering attempts owned favorable reference values.