RESUMEN
Metal-organic gels (MOGs) are a new type of intelligent soft material, which are bridged by metal ions and organic ligands through noncovalent interactions. In this paper, we prepared highly stable P-MOGs, using the classical organic electrochemiluminescence (ECL) luminescence meso-tetra(4-carboxyphenyl)porphine as the organic ligand and Fe3+ as the metal ion. Surprisingly, P-MOGs can stably output ECL signals at a low potential. We introduced P-MOGs into the ECL resonance energy transfer strategy (ECL-RET) and constructed a quenched ECL immunosensor for the detection of the SARS-CoV-2 nucleocapsid protein (SARS-CoV-2-N). In the ECL-RET system, P-MOGs were used as energy donors, and Au@Cu2O@Fe3O4 were selected as energy acceptors. The ultraviolet-visible spectrum of Au@Cu2O@Fe3O4 partially overlaps with the ECL spectrum of P-MOGs, which can effectively touch off the ECL-RET behavior between the donors and receptors. Under the ideal experimental situation, the linear detection range of the SARS-CoV-2-N concentration was 10 fg/mL to 100 ng/mL, and the limit of detection was 1.5 fg/mL. This work has broad application prospects for porphyrin-MOGs in ECL sensing.
Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanopartículas del Metal , Humanos , Mediciones Luminiscentes , SARS-CoV-2 , Técnicas Electroquímicas , Límite de Detección , Inmunoensayo , COVID-19/diagnóstico , Geles , Proteínas de la NucleocápsideRESUMEN
Metal nanoclusters (Me NCs) have become a research hotspot in the field of electrochemiluminescence (ECL) sensing analysis. This is primarily attributed to their excellent luminescent properties and biocompatibility along with their easy synthesis and labeling characteristics. At present, the application of Me NCs in ECL mainly focuses on precious metals, whose high cost, to some extent, limits their widespread application. In this work, Cu NCs with cathode ECL emissions in persulfate (S2O82-) were prepared as signal probes using glutathione as ligands, which exhibited stable luminescence signals and high ECL efficiency. At the same time, CaMnO3 was introduced as a co-reaction promoter to increase the ECL responses of Cu NCs, thereby further expanding their application potential in biochemical analysis. Specifically, the reversible conversion of Mn3+/Mn4+ greatly promoted the generation of sulfate radicals (SO4â¢-), providing a guarantee for improving the luminescence signals of Cu NCs. Furthermore, a short peptide (NARKFYKGC) was introduced to enable the fixation of antibodies to specific targets, preventing the occupancy of antigen-binding sites (Fab fragments). Therefore, the sensitivity of the biosensor could be significantly enhanced by releasing additional Fab fragments. Considering the approaches discussed above, the constructed biosensor could achieve sensitive detection of CD44 over a broad range (10 fg/mL-100 ng/mL), with an ultralow detection limit of 3.55 fg/mL (S/N = 3), which had valuable implications for the application of nonprecious Me NCs in biosensing analysis.
Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Cobre/química , Mediciones Luminiscentes , Luminiscencia , Fragmentos Fab de Inmunoglobulinas , Técnicas Electroquímicas , Límite de Detección , Nanopartículas del Metal/químicaRESUMEN
In this Letter, a sensitive DNA sensing platform was developed using an indium-ion-coordinated 1,1,2,2-tetra(4-carboxylphenyl)ethylene (TPE) metal-organic gel (In-MOG) as an aggregation-induced electrochemiluminescence (AIECL) emitter and nanosurface energy transfer (NSET) as an efficient quenching strategy for detecting aflatoxin B1 (AFB1), the most dangerous food toxin. The coordination occurred in indium ions, and carboxyl groups restricted the internal rotation and vibration of TPE molecules, forcing them to release photons via radiative transitions. The quenchers of microfluidic-produced gold nanoparticles were embedded in a long-tailed triangular DNA structure, where the quenching phenomenon aligned with the theory of ECL-NSET under the overlap of spectra and appropriate donor-acceptor spacing. The proposed analytical method showed a sensitive ECL response to AFB1 in the wide concentration range of 0.50-200.00 ng/mL with a limit of detection of 0.17 ng/mL. Experimental results confirmed that constraining luminescent molecules using coordination and bonding to trigger the AIECL phenomenon was a promising method to prepare signal labels for the trace detection of food toxins.
Asunto(s)
Aflatoxina B1 , Técnicas Electroquímicas , Transferencia de Energía , Mediciones Luminiscentes , Aflatoxina B1/análisis , Oro/química , Nanopartículas del Metal/química , ADN/química , Geles/química , Límite de DetecciónRESUMEN
Metal nanoclusters (NCs) as a new kind of luminophore have acquired sufficient interest, but their widespread application is restricted on account of their relatively low electrochemiluminescence (ECL) efficiency. Then, aqueous metal NCs with high ECL efficiency were strongly anticipated, especially for the ultrasensitive analysis of biomarkers. Herein, a near-infrared (NIR) ECL biosensing strategy for the test of neuron-specific enolase (NSE) was proposed by utilizing N-acetyl-l-cysteine (NAC)- and cysteamine (Cys)-stabilized gold NCs (NAC/Cys-AuNCs) as ECL emitters with the NIR ECL emission around 860 nm and a metal-organic framework/palladium nanocubes (ZIF-67/PdNCs) hybrid as the coreaction accelerator through their admirable electrocatalytic activity. The NIR emission would reduce photochemical injury to the samples and even realize nondestructive analysis with highly strong susceptibility and suitability. Furthermore, the utilization of ZIF-67/PdNCs could improve the ECL response of NAC/Cys-AuNCs by facilitating the oxidation of the coreactant triethylamine (TEA), leading to the production of a larger quantity of reducing intermediate radical TEAâ¢+. Consequently, NAC/Cys-AuNCs with ZIF-67/PdNCs displayed 2.7 fold enhanced ECL emission compared with the single NAC/Cys-AuNCs using TEA as the coreactant. In addition, HWRGWVC (HWR), a heptapeptide, was introduced to immobilize antibodies for the specially binding Fc fragment of the antibodies, which improved the binding efficiency and sensitivity. As a result, a "signal-on" immunosensor for NSE analysis was obtained with an extensive linear range of 0.1 to 5 ng/mL and a low limit of detection (0.033 fg/mL) (S/N = 3). This study provides a wonderful method for the development of an efficient nondestructive immunoassay.
Asunto(s)
Biomarcadores , Técnicas Electroquímicas , Oro , Mediciones Luminiscentes , Nanopartículas del Metal , Estructuras Metalorgánicas , Oro/química , Estructuras Metalorgánicas/química , Nanopartículas del Metal/química , Inmunoensayo/métodos , Técnicas Electroquímicas/métodos , Biomarcadores/análisis , Cobalto/química , Humanos , Fosfopiruvato Hidratasa/análisis , Límite de Detección , Cisteamina/química , Paladio/química , Rayos Infrarrojos , Técnicas Biosensibles/métodosRESUMEN
The unique optoelectronic and tunable luminescent characteristics of copper nanoclusters (Cu NCs) make them extremely promising as luminophores. However, the limited luminescence intensity and stability of Cu NCs have restricted their application in the field of electrochemiluminescence (ECL). Herein, a self-assembly-induced enhancement strategy was successfully employed to enhance the cathodic ECL performance of flexible ligand-stabilized Cu NCs. Specifically, Cu NCs form ordered sheetlike structures through intermolecular force. The restriction of ligand torsion in this self-assembled structure leads to a significant improvement in the ECL properties of the Cu NCs. Experimental results demonstrate that the assembled nanoscale Cu NC sheets exhibit an approximately three-fold increase in cathodic ECL emission compared to the dispersed state of Cu NCs. Furthermore, assembled nanoscale Cu NCs sheets were utilized as signal probes in conjunction with a specific short peptide derived from the catalytic structural domain of matrix metalloproteinase 14 (MMP 14) as the identification probe, thereby establishing a split-type ECL sensing platform for the quantification of NMP 14. The investigation has revealed the exceptional performance of assembled nanoscale Cu NCs sheets in ECL analysis, thus positioning them as novel and promising signal probes with significant potential in the field of sensing.
Asunto(s)
Cobre , Técnicas Electroquímicas , Mediciones Luminiscentes , Metaloproteinasa 14 de la Matriz , Nanopartículas del Metal , Cobre/química , Técnicas Electroquímicas/métodos , Nanopartículas del Metal/química , Metaloproteinasa 14 de la Matriz/metabolismo , Metaloproteinasa 14 de la Matriz/análisis , Electrodos , HumanosRESUMEN
Inorganic/organic heterojunctions show promising applications as high-performance sensing platforms for photoelectrochemical (PEC) immunosensors. This work reports constructing a PEC biosensor for CA15-3 based on a self-assembled perylene diimide (PDI) nanowire sensitized In2O3@MgIn2S4 S-scheme heterojunction platform. P-type semiconductor Cu2O nanoparticles were designed as a signal burst source and were used as immunoassay labels. The carboxyl group on self-assembled PDI nanowires eliminates the step of additional surface functionalization for covalent immobilization of the capture elements. The π-π stacking of PDI enhances electron generation efficiency, while the carboxylic acid groups on PDI promote electron transfer. The performance of the constructed sensor was validated using CA15-3 as a model. The experimental results showed that the sensor based on In2O3@MgIn2S4/PDI has excellent selectivity, stability, and reproducibility, and can sensitively detect CA15-3 in the range of 0.001-100 U·mL-1 with the detection limit of 0.00056 U·mL-1. The sensor has a broad application prospect. It is hoped that this research work based on the unique advantages of the organic compound PDI will inspire other researchers to design light-responsive materials and promote the development of the field of photoelectrochemical sensing.
RESUMEN
In this paper, an electrochemiluminescence (ECL) immunosensor for ultrasensitive detection of CA19-9 was constructed using ternary compound CdSSe nanoparticles as ECL emitter. The immunosensor employs Cu2S and gold-doped diindium trioxide (Au-In2O3) nanocubes as coreaction accelerators to achieve a double-amplification strategy. In general, a hexagonal maple leaf-shaped Cu2S with a large surface area was selected as the template, and the in situ growth of CdSSe on its surface was achieved using a hydrothermal method. The presence of Cu2S not only inhibited the aggregation of CdSSe nanoparticles to reduce their surface energy but also acted as an ECL cathode coreaction promoter, facilitating the generation of SO4â¢-. Consequently, the ECL intensity of CdSSe was significantly enhanced, and the reduction potential was significantly lower. In addition, the template method was employed to synthesize Au-In2O3 nanocubes, which offers the advantage of directly connecting materials with antibodies, resulting in a more stable construction of the immunosensor. Furthermore, In2O3 serves as a coreaction promoter, enabling the amplification strategy for ECL intensity of CdSSe, thus contributing to the enhanced sensitivity and performance of the immunosensor. The constructed immunosensor exhibited a wide linear range (100 µU mL-1 to 100 U mL-1) and a low detection limit of 80 µU mL-1, demonstrating its high potential and practical value for sensitive detection of CA19-9.
Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Antígeno CA-19-9 , Inmunoensayo/métodos , Técnicas Biosensibles/métodos , Pruebas Inmunológicas , Semiconductores , Mediciones Luminiscentes/métodos , Técnicas Electroquímicas/métodos , Límite de Detección , OroRESUMEN
In this work, an electrochemiluminescence (ECL) quenching system using multimetal-organic frameworks (MMOFs) was proposed for the sensitive and specific detection of heart-type fatty acid-binding protein (H-FABP), a marker of acute myocardial infarction (AMI). Bimetallic MOFs containing Ru and Mn as metal centers were synthesized via a one-step hydrothermal method, yielding RuMn MOFs as the ECL emitter. The RuMn MOFs not only possessed the strong ECL performance of Ru(bpy)32+ but also maintained high porosity and original metal active sites characteristic of MOFs. Moreover, under the synergistic effect of MOFs and Ru(bpy)32+, RuMn MOFs have more efficient and stable ECL emission. The trimetal-based MOF (FePtRh MOF) was used as the ECL quencher because of the electron transfer between FePtRh MOFs and RuMn MOFs. In addition, active intramolecular electron transfer from Pt to Fe or Rh atoms also occurred in FePtRh MOFs, which could promote intermolecular electron transfer and improve electron transfer efficiency to enhance the quenching efficiency. The proposed ECL immunosensor demonstrated a wide dynamic range and a low detection limit of 0.01-100 ng mL-1 and 6.8 pg mL-1, respectively, under optimal conditions. The ECL quenching system also presented good specificity, stability, and reproducibility. Therefore, an alternative method for H-FABP detection in clinical diagnosis was provided by this study, highlighting the potential of MMOFs in advancing ECL technology.
Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Inmunoensayo/métodos , Técnicas Biosensibles/métodos , Reproducibilidad de los Resultados , Proteína 3 de Unión a Ácidos Grasos , Mediciones Luminiscentes/métodos , Metales , Técnicas Electroquímicas/métodos , Límite de Detección , Nanopartículas del Metal/químicaRESUMEN
Highly responsive interface of semiconductor nanophotoelectrochemical materials provides a broad development prospect for the identification of low-abundance cancer marker molecules. This work innovatively proposes an efficient blank WO3/SnIn4S8 heterojunction interface formed by self-assembly on the working electrode for interface regulation and photoregulation. Different from the traditional biomolecular layered interface, a hydrogel layer containing manganese dioxide with a wide light absorption range is formed at the interface after an accurate response to external immune recognition. The formation of the hydrogel layer hinders the effective contact between the heterojunction interface and the electrolyte solution, and manganese dioxide in the hydrogel layer forms a strong competition between the light source and the substrate photoelectric material. The process effectively improves the carrier recombination efficiency at the interface, reduces the interface reaction kinetics and photoelectric conversion efficiency, and thus provides strong support for target identification. Taking advantage of the process, the resulting biosensors are being explored for sensitive detection of human epidermal growth factor receptor 2, with a limit of detection as low as 0.037 pg/mL. Also, this study contributes to the advancement of photoelectrochemical biosensing technology and opens up new avenues for the development of sensitive and accurate analytical tools in the field of bioanalysis.
Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Compuestos de Manganeso , Óxidos , Receptor ErbB-2 , Humanos , Técnicas Electroquímicas/métodos , Óxidos/química , Compuestos de Manganeso/química , Receptor ErbB-2/inmunología , Receptor ErbB-2/metabolismo , Hidrogeles/química , Procesos Fotoquímicos , Límite de Detección , Electrodos , Inmunoensayo/métodos , Tungsteno/químicaRESUMEN
In this letter, a sensitive microfluidic immunosensor chip was developed using tetrakis(4-aminophenyl)ethene (TPE)-derived covalent organic frameworks (T-COF) as aggregation-induced electrochemiluminescence (AIECL) emitters and nanobodies as efficient immune recognition units for the detection of thymic stromal lymphopoietin (TSLP), a novel target of asthma. The internal rotation and vibration of TPE molecules were constrained within the framework structure, forcing nonradiative relaxation to convert into pronounced radiative transitions. A camel-derived nanobody exhibited superior specificity, higher residual activity and epitope recognition postcuring compared to monoclonal antibodies. Benefiting from the affinity between silver ions (Ag+) and cytosine (C), a double-stranded DNA (dsDNA) embedded with Ag+ was modified onto the surface of TSLP. A positive correlation was obtained between the TSLP concentration (1.00 pg/mL to 4.00 ng/mL) and ECL intensity, as Ag+ was confirmed to be an excellent accelerator of the generation of free radical species. We propose that utilizing COF to constrain luminescent molecules and trigger the AIECL phenomenon is another promising method for preparing signal tags to detect low-abundance disease-related markers.
Asunto(s)
Citocinas , Técnicas Electroquímicas , Mediciones Luminiscentes , Estilbenos , Linfopoyetina del Estroma Tímico , Citocinas/análisis , Citocinas/metabolismo , Estilbenos/química , Humanos , Estructuras Metalorgánicas/química , Técnicas Biosensibles , Inmunoensayo/métodos , Anticuerpos de Dominio Único/química , Anticuerpos de Dominio Único/inmunología , Técnicas Analíticas Microfluídicas/instrumentaciónRESUMEN
The elimination of aggregation-caused quenching of polycyclic aromatic hydrocarbons by metal-ligand coordination is of immense scientific interest in solid-state electrochemiluminescence (ECL) sensing. Herein potassium ion (K+)-mediated J-aggregate K-PTC MOF (PTCA, perylene-3,4,9,10-tetracarboxylic) was synthesized and employed to formulate an ECL immunosensor for biomarker detection. The coordination-driven aggregates are arranged in an end-to-end side mode, which overcomes the aggregation-caused quenching related to PTCA concentration. Compared with PTCA, K-PTC MOF shows a more stable ECL emission with an unprecedented red shift to 718 nm and is equipped with ECL activity for analytical applications at a voltage of -1.1 V. Considering the requirements of accurate detection, metal-phenolic bioactive nanoparticles (MPNPs) were synthesized for the construction of a sandwich sensing platform to realize the steady-state regulation of ECL. As proof of applicability, a constructive experiment was carried out with neuron-specific enolase (NSE), a marker of small cell lung cancer (SCLC), as a targeted analyte. With optimal requirements, the configuration can provide a detection range of 10 pg/mL to 50 ng/mL and a detection limit of 7.4 pg/mL, accompanied by sufficient practical analytical performance. Collectively, this paradigm provides a deeper understanding of the ECL characteristics of coordination-driven J-aggregation and provides more possibilities for the development of ECL patterns based on luminescent metal-organic frameworks.
Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Mediciones Luminiscentes , Técnicas Electroquímicas , Inmunoensayo , Potasio , Biomarcadores , Límite de DetecciónRESUMEN
In this work, a sensitive signal-on electrochemiluminescence biosensor using liposome-encapsuled 1,1,2,2-tetra(4-carboxylphenyl)ethylene (TPE) as a promising aggregation-induced electrochemiluminescence (AIECL) emitter for detection of biomarkers was developed. Aggregation-induced enhancement occurs internally through the spatial confinement effect and intramolecular self-encapsulation of encapsulating TPE and triethylamine (TEA) molecules in liposome cavities. Peptide sequence WTGWCLNPEESTWGFCTGSF (WF-20) was used to replace the antibody for reducing the steric hindrance of the sensing surface while taking into account the affinity. The proposed sensing strategies showed satisfactory properties for detection of human epidermal growth factor receptor 2 (HER2) ranging from 0.01 to 500 ng/mL with a limit of detection of 6.65 pg/mL. The results confirmed that encapsulation of luminescent molecules in the vesicle structure for triggering the AIECL phenomenon is a promising method to prepare a signal label for a trace detection biomarker.
Asunto(s)
Técnicas Biosensibles , Estilbenos , Humanos , Liposomas , Receptor ErbB-2 , Estilbenos/química , Técnicas Biosensibles/métodos , Mediciones Luminiscentes/métodos , Técnicas Electroquímicas/métodos , Límite de DetecciónRESUMEN
Inspired by the signal accumulation of circular DNA strand displacement reactions (CD-SDRs) and the in situ generation of silver nanoclusters (AgNCs) from signature template sequences, a dual-signal integrated aptasensor was designed for microcystin-LR (MC-LR) detection. The aptamer was programmed to be included in an enzyme-free CD-SDR, which utilized MC-LR as the primer and outputted the H1/H2 dsDNA in a continuous manner according to the ideal state. Ingeniously, H1/H2 dsDNA was enriched with signature template sequences, allowing in situ generation of AgNCs signal probes. To enhance the signal amplification performance, co-reaction acceleration strategies and CRISPR-Cas12a nucleases were invoked. The H1/H2 dsDNA could trigger the incidental cleavage performance of CRISPR-Cas12a nucleases: cis-cleavage reduced signature template sequences for the synthetic AgNCs, while trans-cleavage enabled fluorescence (FL) analysis. Meanwhile, AuPtAg was selected as the substrate material to facilitate the S2O82- reduction reaction for enhancing the electrochemiluminescence (ECL) basal signals. ECL and FL detection do not interfere with each other and have improved accuracy and sensitivity, with limits of detection of 0.011 and 0.023 pmol/L, respectively. This widens the path for designing dual-mode sensing strategies for signal amplification.
Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Nanopartículas del Metal , ADN Circular , Plata , ADN/genética , Aptámeros de Nucleótidos/genética , Límite de DetecciónRESUMEN
Mercury (Hg2+) is a highly toxic element and can seriously affect human health. This work proposed a photoelectrochemical (PEC) sensor with a Z-scheme Fe2O3/CdS heterostructure and two thymine-rich DNA strands (DNA-1 and Au@DNA-2) for sensitive detection of Hg2+. The light excitation of the Fe2O3/CdS composite accelerated the electron transfer among Fe2O3, CdS, and the electrode to produce a stable photocurrent response. Upon the recognition of Hg2+ to thymine bases (T) in two DNA strands to form a stable T-Hg2+-T biomimetic structure, the photocurrent response increased with the increasing concentration of Hg2+ due to the opening of electronic transmission channels from Au nanoparticles to Fe2O3/CdS nanocomposite. Under the optimal conditions screened by the Box-Behnken experiments, the proposed PEC sensor showed excellent analytical performance for Hg2+ detection with high sensitivity, a detection limit of 0.20 pM at a signal-to-noise ratio of 3, high selectivity, a detectable concentration range of 1 pM-100 nM, and acceptable stability. The good recovery and low relative standard deviation for the analysis of Hg2+ in lake and tap water samples demonstrated the potential application of the designed Z-scheme Fe2O3/CdS heterostructure in the PEC detection of heavy metal ions.
Asunto(s)
Técnicas Biosensibles , Mercurio , Nanopartículas del Metal , Humanos , Mercurio/análisis , Oro/química , Nanopartículas del Metal/química , Timina/química , ADN/química , Límite de Detección , Técnicas ElectroquímicasRESUMEN
High-performance electrochemiluminescence is a significant approach for the examination of disease biomarkers, and the utilization of innovative electrochemiluminescence detection systems represents a viable strategy to enhance the efficacy of ECL analysis. In this work, the biomimetic engineering metal-organic framework (MOF-818) has realized the ultrasensitive ECL immunoassay of disease markers based on the guidance of the free radical scavenging strategy provided by the antioxidant cascade. Initially, we synthesized a hydrogen-bonded organic framework (HOF) consisting of luminol and three active ligands based on simple room-temperature self-assembly. The luminol-HOF (L-HOF) showed more stable and brighter ECL luminescence activity than the monomer due to the nano-confinement enhancement of the coordinated luminol units. Subsequently, MOF-818 with biomimetic superoxide dismutase (SOD) and catalase (CAT) activities were recruited for the first time as quenching agents for sandwich immunoassay mode. The enzyme activity leads to the reverse transformation of superoxide anion radicals (O2-) and further antioxidant decomposition, decreasing in the responsiveness of luminol ECL signals. Using carcinoembryonic antigen (CEA) as an analytical model, a detection limit of 0.457 pg/mL was obtained within a detection range of 0.001-50 ng/mL. We believe that this novel sandwich sensing model based on enzyme activity provides a meaningful potential tool for precise detection, expanding the broader application of nanoenzymes in analysis.
Asunto(s)
Antioxidantes , Estructuras Metalorgánicas , Biomimética , Luminol , Hidrógeno , InmunoensayoRESUMEN
The low electrochemiluminescence (ECL) efficiency issue of zirconia (ZrO2) has been a pressing problem since its discovery. In this study, a bandgap-regulated ECL enhancement strategy was developed to improve the ECL efficiency of ZrO2. Specifically, through the calcination of metal-organic frameworks (MOFs), the MOF-derived bimetallic oxide ZrCuO3 was synthesized. Compared to ZrO2, the synthesized ZrCuO3 exhibited a narrower bandgap and higher electron transfer efficiency, leading to enhanced ECL efficiency. Further investigation of the ECL emitter revealed that ZrCuO3 exhibited multimodal ECL emission: annihilation ECL and co-reactant participation ECL (including anodic ECL with tripropylamine as a co-reactant and cathodic ECL with K2S2O8 as a co-reactant). The anodic ECL with the highest efficiency was selected as the main mode for detecting the target in the aptasensor. Annihilation ECL and cathodic ECL served as alternative modes to ensure stability and continuity of the sensing system. Based on the bandgap-regulated strategy of ZrCuO3, a sensing chip with ITO as the working electrode was designed for the sensitive detection of florfenicol (FF). The constructed signal "off-on-off" aptasensor exhibited excellent detection performance for FF in the range of 0.0005-200 ng/mL. The proposed method provided a novel strategy for the analysis of other antibiotics or biomolecules.
Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , Mediciones Luminiscentes/métodos , Fotometría , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Límite de DetecciónRESUMEN
A controlled-release strategy can meet the needs of sensitive environmental monitoring for pollutants through a self-on/off mode. In this work, an electrochemiluminescence (ECL) biosensor with controlled-release triggering electrostatic attraction elimination and biomolecular stimulated response strategies was constructed to detect environmental steroid hormones sensitively. The blocked pores on the aminated mesoporous silica nanocontainers were opened by specific binding between the trenbolone (TB) antigen and the antibody. The released l-cysteine counteracted the negative charge on the MnO2 NF surface through the redox reaction between -SH and MnO2, making the electrostatic interaction between the MnO2 NFs and the Ru(dcbpy)32+ disappear. Ru(dcbpy)32+ released an ECL signal on the electrode, thus completing the controlled-release triggering electrostatic attraction elimination strategy. In addition, with the TB antibody as the target and the competition strategy between the TB antigen and the standard substance, the constructed controlled-release ECL biosensor was used to detect the TB standard substance. Moreover, MnO2 NFs as the substrate of the ECL biosensor increased the active specific surface area of the electrode, effectively catalyzing the production of OH⢠and O2â¢-, thus endowing the ECL biosensor with coreactant-catalytic enhancement characteristic and further improving its ECL performance. This sensitive signal response brought about a low limit of detection of 2.53 fg/mL for the constructed ECL biosensor, which contributed a feasible idea for efficient trace analysis of pollutants in the environment.
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Contaminantes Ambientales , Compuestos de Manganeso , Preparaciones de Acción Retardada , Óxidos , Electricidad Estática , Acetato de Trembolona , AnticuerposRESUMEN
Metal oxide nanomaterials have garnered significant attention in the field of electrochemiluminescence (ECL) sensing due to their efficient, stable, and nontoxic properties. However, the current research on metal oxide nanomaterials has primarily focused on their cathodic luminescence properties, with limited reports on their anodic ECL properties. In this study, we utilized MOF-derived ZrO2 nanomaterials as luminophores to generate stable anodic ECL signals in the presence of the coreactant tripropylamine (TPrA). Additionally, a signal-enhancing immunosensor was developed to analyze D-dimer by incorporating the coreaction accelerator Cu-doped TiO2 (TiO2-Cu). The ZrO2 synthesized by calcining UiO-67 demonstrated nontoxicity and biocompatibility, exhibiting efficient and stable ECL emission in a TPrA solution. The inclusion of TiO2-Cu as a coreaction accelerator in the immunosensor resulted in the formation of a ternary system of ZrO2/TiO2-Cu/TPrA. The Cu doping effectively narrowed the bandgap of TiO2 and enhanced its conductivity. As a substrate, TiO2-Cu reacted with more TPrA, generating sufficient free radicals to effectively enhance the ECL signal of ZrO2. In this article, a short peptide ligand, NFC (NARKFYKGC), was designed to immobilize antibodies and maintain the activity of antigen-binding sites during the construction of the immunosensor. The developed immunosensor was used for the accurate detection of D-dimers, with a wide linear range of 0.05-600 ng/mL and a low detection limit of 21 pg/mL..
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Técnicas Biosensibles , Nanoestructuras , Inmunoensayo , ÓxidosRESUMEN
To ensure drinking water quality, the development of rapid and accurate analytical methods is essential. Herein, a highly sensitive electrochemiluminescence (ECL) aptasensor-based on the signal on-off-on strategy was developed to detect the water pollutant microcystin-LR (MC-LR). This strategy was based on a newly prepared ruthenium-copper metal-organic framework (RuCu MOF) as the ECL signal-transmitting probe and three types of PdPt alloy core-shell nanocrystals with different crystal structures as signal-off probes. Compounding the copper-based MOF (Cu-MOF) precursor with ruthenium bipyridyl at room temperature facilitated the retention of the intrinsic crystallinity and high porosity of the MOFs as well as afforded excellent ECL performance. Since bipyridine ruthenium in RuCu MOFs could transfer energies to the organic ligand (H3BTC), the ultra-efficient ligand luminescent ECL signal probe was finally obtained, which greatly improved the sensitivity of the aptasensor. To further improve the sensitivity of the aptasensor, the quenching effects of noble metal nanoalloy particles with different crystal states were investigated, which contained PdPt octahedral (PdPtOct), PdPt rhombic dodecahedral (PdPtRD), and PdPt nanocube (PdPtNC). Among them, the PdPtRD nanocrystal exhibited higher activity and excellent durability, stemming from the charge redistribution caused by the hybridization of Pt and Pd atoms. Moreover, PdPtRD could also load more -NH2-DNA strands because it exposed more active sites with a large specific surface area. The fabricated aptasensor exhibited outstanding sensitivity and stability in MC-LR detection, with a linear detection range of 0.0001-50 ng mL-1. This study provides valuable directions for the application of alloy nanoparticles of noble metals and bimetallic MOFs in the field of ECL immunoassay.
Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Estructuras Metalorgánicas , Rutenio , Estructuras Metalorgánicas/química , Cobre/química , Rutenio/química , Ligandos , Mediciones Luminiscentes/métodos , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Aleaciones , Nanopartículas del Metal/química , Límite de DetecciónRESUMEN
Herein, a high-efficiency biosensor based on ternary electrochemiluminescence (ECL) system was constructed for procalcitonin (PCT) detection. Specifically, silver nanoclusters (Ag NCs) with stable luminescence properties were prepared with small-molecule lipoic acid (LA) as the ligand, and its ECL emission in persulfate (S2O82-) was first reported. Meanwhile, the prepared Ag NCs possessed ligand-to-metal charge-transfer characteristics, thus transferring energy from LA to Ag+ for luminescence. Based on the small particle size, good biocompatibility, and molecular binding ability, Ag NCs-LA was used as an ideal luminescent probe. In addition, α-Fe2O3-Pt was introduced to facilitate the activation of S2O82-, thereby generating more sulfate radicals to react with the free radicals of Ag NCs to enhance ECL emission. The synergistic effect of the variable valence state of transition metals and high catalytic activity of noble metals endows α-Fe2O3-Pt with excellent catalytic ability for S2O82-. Importantly, the sensing mechanism was systematically demonstrated by UV-vis, fluorescence, and ECL analysis, as well as density functional theory calculations. At last, NKFRGKYKC was designed for specific immobilization of antibodies, thus releasing the antigen binding sites to improve the antigen recognition efficiency. Based on this, the developed biosensor showed high sensitivity for PCT detection, with a wide linear range (10 fg/mL-100 ng/mL) and a low detection limit (3.56 fg/mL), which could be extended to clinical detection of multiple biomarkers.