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The construction of heterostructure photoelectrodes can enhance the performance of photoelectrochemical (PEC) sensors. However, it is still a critical challenge to achieve efficient transfer of interface carriers. In this paper, we propose a strategy of "photo-modulated interface charge" to design a PEC sensor based on a hollow hexagonal tubular In2S3/AgInS2 in situ Z-type heterojunction for the susceptible detection of Programmed Death-ligand 1 (PD-L1). The hollow structured In2S3/AgInS2 is ingeniously synthesized employing indium-sourced MIL-68 as a sacrificial template and in situ cation exchange technique. This composite material has close contact interfaces due to in situ growth, which facilitates the spontaneous establishment of a robust and stable built-in electric field between the interfaces. Moreover, the inner cavity structure promotes multiple light refractions and scatterings, significantly enhancing light trapping capability. Under the influence of both light irradiation and electric field force, the migration direction of the interfacial charge is reversed, forming a Z-transfer path, which effectively delays the compounding of the electron-hole pairs (e-/h+) and further improves the sensitivity of the sensor. The minimum detection threshold of the PEC sensor is 26.58 fg/mL, and the feasibility of real samples is investigated, providing new insights for early diagnosis and prognostic treatment of diseases.
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OBJECTIVES: To explore the effects of iris xanthin on airway inflammation, airway remodeling, and the high mobility group box 1 protein (HMGB1)/Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) pathway in asthmatic young mice. METHODS: Sixty male BALB/c young mice were randomly assigned into six groups: a blank group, a model group, a dexamethasone group, and low, medium, and high dose groups of iris xanthin, with ten mice per group. Asthma models were induced through intraperitoneal injections of a sensitizing agent [ovalbumin (OVA) 20 µg + aluminum hydroxide gel 2 mg], followed by 4% OVA aerosol inhalation. Lung function was measured using a pulmonary function tester to determine lung volume (LV), resting ventilation per minute (VE), and airway reactivity (Penh value). Hematoxylin-eosin (HE) staining was employed to examine and analyze airway remodeling. The contents of interleukin (IL)-1ß, IL-6, and tumor necrosis factor alpha (TNF-α) in bronchoalveolar lavage fluid were quantified using ELISA. Real-time fluorescence quantitative polymerase chain reaction and Western blot analysis were used to assess the expression of HMGB1/TLR4/NF-κB pathway-related mRNA and proteins in lung tissues. RESULTS: Compared to the model group, the dexamethasone and iris xanthin-treated groups (low, medium, and high doses) exhibited significant increases in LV and VE (P<0.05), with incremental dose-dependent increases observed in the iris xanthin groups. Additionally, Penh values, IL-1ß, IL-6, TNF-α, and airway remodeling indicators, along with mRNA levels of HMGB1, TLR4, and NF-κB p65 and protein levels of HMGB1, TLR4, and p-NF-κB p65, were all reduced (P<0.05) in a dose-dependent manner. When compared to the dexamethasone group, the low and medium dose iris xanthin groups showed decreases in LV and VE (P<0.05), whereas Penh values, IL-1ß, IL-6, TNF-α, and airway remodeling indicators, along with mRNA levels of HMGB1, TLR4, NF-κB p65 and protein levels of HMGB1, TLR4, and p-NF-κB p65, were increased (P<0.05). No significant differences were noted in these indices between the high dose iris xanthin group and the dexamethasone group (P>0.05). CONCLUSIONS: Iris xanthin can effectively alleviates airway inflammation and inhibits airway remodeling in asthmatic young mice, possibly through the suppression of the HMGB1/TLR4/NF-κB pathway.
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Remodelação das Vias Aéreas , Asma , Proteína HMGB1 , Camundongos Endogâmicos BALB C , NF-kappa B , Transdução de Sinais , Receptor 4 Toll-Like , Animais , Remodelação das Vias Aéreas/efeitos dos fármacos , Asma/tratamento farmacológico , Asma/metabolismo , Masculino , Camundongos , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
An electrochemical immunosensor based on the novel high efficiency catalytic cycle amplification strategy for the sensitive detection of cardiac troponin I (cTnI). With its variable valence metal elements and spiny yolk structure, the Cu2O/CuO@CeO2 nanohybrid exhibits high speed charge mobility and exceptional electrochemical performance. Notably, fluorite-like cubic crystal CeO2 shell would undergo redox reaction with Cu2O core, which successfully ensures the continuous recycling occurrence of "fresh" Cu (II)/Cu (I) and Ce (â £)/Ce (â ¢) pairs at the electrode interface. The "fresh" active sites continue to emerge constantly, resulting in a significant increase in the current signal. In light of the electrochemical characterization, the electron transfer pathway and catalytic cycle mechanism among CeO2, Cu2O and CuO were further discussed. The developed electrochemical immunosensor detected cTnI from 100 fg/mL to 100 ng/mL with a LOD of 15.85 fg/mL under optimal conditions. The analysis results indicate that the immunosensor would hold promise for broad application prospects in the biological detection for other biomarkers.
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Técnicas Biossensoriais , Cobre , Técnicas Eletroquímicas , Limite de Detecção , Troponina I , Troponina I/análise , Troponina I/sangue , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Cobre/química , Catálise , Humanos , Imunoensaio/métodos , Cério/químicaRESUMO
An interfacial galvanic replacement strategy to controllable synthesize palladium nanoparticles (Pd NPs)-modified NiFe MOF nanocomposite on nickel foam, which served as an efficient sensing platform for quantitative determination of dopamine (DA). Pd NPs grown in situ on the nanosheets of NiFe MOF via self-driven galvanic replacement reaction (GRR) and well uniform distribution was achieved. This method effectively reduced the aggregation of metallic nanoparticles and significantly promoted the electron transfer rate during the electrochemical process, leading to improved electrocatalytic activity for DA oxidation. Remarkably, the precisely constructed biosensor achieved a low detection limit (LOD) of 0.068 µM and recovery of 94.1% (RSD 6.7%, N = 3) for simulated real sample detection and also exhibited superior selectivity and stability. The results confirmed that the as-fabricated Pd-NiFe/NF composite electrode could realize the quantitative determination of DA and showed promising prospects in real sample biosensing.
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Técnicas Biossensoriais , Dopamina , Estruturas Metalorgânicas , Nanoestruturas , Dopamina/análise , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/normas , Níquel/química , Eletrodos/normas , Paládio/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Microscopia Eletrônica de Varredura , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/ultraestrutura , Sensibilidade e Especificidade , Condutividade Elétrica , Microscopia Eletrônica de Transmissão , Ferro/química , Reprodutibilidade dos TestesRESUMO
Nanosheet arrays with stable signal output have become promising photoactive materials for photoelectrochemical (PEC) immunosensors. However, an essential concern is the facile recombination of carriers in one-component nanoarrays, which cannot be readily prevented, ultimately resulting in weak photocurrent signals. In this study, an immunosensor using gold nanoparticle-anchored BiOI/Bi2S3 nanosheet arrays (BiOI/Bi2S3/Au) as a signal converter was fabricated for sensitive detection of cardiac troponin I (cTnI). The ternary nanosheet arrays were prepared by a simple method in which Bi2S3 was well-coated on the BiOI surface by in situ growth, whereas the addition of Au further improved the photoelectric conversion efficiency and could link more antibodies. The three-dimensional (3D) ordered sheet-like network array structure and BiOI/Bi2S3/Au ternary nanosheet arrays showed stable and high photoelectric signal output and no significant difference in signals across different batches under visible light excitation. The fabricated immunosensor has a sensitive response to the target detection marker cTnI in a wide linear range of 500 fg/mL to 50 ng/mL, and the detection limit was 32 fg/mL, demonstrating good stability and selectivity. This work not only shows the great application potential of ternary heterojunction arrays in the field of PEC immunosensors but also provides a useful exploration for improving the stability of immunosensors.
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Técnicas Biossensoriais , Nanopartículas Metálicas , Troponina I , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Ouro/química , Imunoensaio/métodos , Limite de Detecção , Troponina I/química , Troponina I/imunologia , Bismuto/químicaRESUMO
Graphitic carbon nitride (g-C3N4) is a promising metal-free photocatalyst; however, its high carrier recombination rate and insufficient redox capacity limit its degradation effect on antibiotics. In order to overcome these shortcomings, the photocatalytic activity is improved by regulating the spin polarization state, constructing the internal electric field, and applying the external piezoelectric field. In this paper, the chlorine-doped and nitrogen-deficient porous carbon nitride composite carbon quantum dots (Nv-Cl/UPCN@CQD) has been synthesized successfully. The doping position of chlorine and spin polarization properties are verified by DFT calculation. The key intermediates *O2- and *OOH for the synthesis of reactive oxygen species were detected by in-situ infrared testing, which promotes the production of â¢O2- and H2O2. The degradation rate constant of Nv-Cl/UPCN@CQD for removal of tetracycline is 8.45 times higher than that of g-C3N4. The active oxygen production and degradation efficiency of piezoelectric photocatalysis under the synergistic effect of intense stirring and vis-light irradiation are much higher than those of photocatalysis and piezoelectric catalysis, and the conversion of H2O2 to â¢OH is promoted by piezoelectric field. This paper provides a reliable way to improve the performance of piezoelectric photocatalysts by adjusting their energy band, electronic structure and piezoelectric force.
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Cloro , Pontos Quânticos , Peróxido de Hidrogênio , Antibacterianos , Nitrogênio , Pontos Quânticos/química , CatáliseRESUMO
Lanthanide metal-organic frameworks (Ln-MOFs) broaden the optical sensing applications of lanthanide ions due to the antenna effect between organic ligands and metals. However, the sensitization ability of the ligand to metal ions is limited, and maximizing the sensitization of the electrochemiluminescence behavior of Eu3+ is still a challenge for the application of Ln-MOFs. Therefore, under the guidance of the "cascade sensitization mechanism" based on the antenna effect sensitizing the electrochemiluminescence of bimetallic Ln-MOFs, we proposed Eu/Tb-MOFs with high luminescence intensity as a signal probe. According to the antenna effect, the conjugated structure and high extinction coefficient of the benzene ring of 2-amino terephthalic acid (NH2-BDC) can enhance the ECL luminescence intensity of Eu/Tb-MOFs. Tb3+ can act as an energy bridge between NH2-BDC and Eu3+, buffering the energy gap. The bimetallic sensitization is formed between Tb3+ and Eu3+, which can inhibit the reverse internal flow of energy and ensure the high luminous efficiency of Eu3+. In addition, the nanosphere mixed valence Fe3O4 as a co-reactant accelerator promotes the formation of transient free radical SO4â¢- through the valence change of Fe2+/Fe3+. The ECL immunosensor constructed by luminophores Eu/Tb-MOFs and nanosphere Fe3O4 provided a new explanation for the ECL self-luminous of Eu/Tb-MOFs.
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Electrochemical immunosensors have gained considerable attention in detecting human disease markers due to their excellent specificity, high sensitivity, and facile operation. Herein, a rational-designed sandwich-type electrochemical immunosensor is constructed for the sensitive detection of cardiac troponin I (cTnI) using nitrogen-doped carbon nanotubes loaded with gold nanoparticles (Au NPs/N-CNTs) as substrate and highly active mesoporous palladium-nitrogen nanocubes (meso-PdN NCs) as secondary antibody markers. Benefitting from its large specific surface area (638.04 m2 g-1) and high nitrogen content, novel polydopamine (PDA)/ halloysite nanotubes (HNTs) hybrid derived one-dimensional (1D) N-CNTs can provide more binding sites for the in-situ growth of Au NPs to connect Ab1. Furthermore, as an ideal substrate material, Au NPs/N-CNTs exhibit finely tuned mesoporous structures and outstanding conductivity, which facilitate the mass and electron transfer during the electrocatalysis process. Besides, highly concave surfaces and crystalline mesopores of meso-PdN NCs expose more surfaces and crevices, providing abundant reactive sites for H2O2 reduction. Remarkably, the as-obtained immunosensor presented a wide linear range (from 10 fg mL-1 to 100 ng mL-1) and an excellent low detection limit (9.85 fg mL-1). This study may offer new insights into the precise fabrication of efficient electrochemical immunosensors for various clinical diagnosis applications.
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Técnicas Biossensoriais , Técnicas Eletroquímicas , Ouro , Limite de Detecção , Nanopartículas Metálicas , Nanotubos de Carbono , Paládio , Troponina I , Ouro/química , Troponina I/análise , Troponina I/sangue , Nanopartículas Metálicas/química , Humanos , Nanotubos de Carbono/química , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Técnicas Biossensoriais/métodos , Paládio/química , Nitrogênio/química , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologiaRESUMO
Copper nanoclusters (Cu NCs) are highly promising nanomaterials in the field of electrochemiluminescence (ECL). Nevertheless, their limited stability and efficiency have impeded their practical applications. Here, we introduced a novel supramolecular anchoring strategy resulting in the creation of exceptionally stable Cu NCs (CET-Cu NCs) with remarkable ECL properties. Specifically, CET-Cu NCs exhibited a relative ECL efficiency (ΦECL) of 62% based on the annihilation ECL efficiency of [Ru(bpy)3]2+ (100%), with tripropylamine employed as a coreactant. Moreover, CET-Cu NCs can generate ECL emission through multiple different paths, which enables them to serve as signal probes in a wider range of testing scenarios, thereby enhancing the reliability and robustness of sensing and analytical systems. To demonstrate the practical utility, CET-Cu NCs were selected as an ECL signal probe for a sensing platform that facilitated ultrasensitive detection of progesterone via oriented immobilization technology and antibody/aptamer sandwich assays. This study surmounted the barriers to the practical application of Cu NCs through the implementation of a supramolecular anchoring strategy, thereby providing enhanced utility of Cu NCs in ECL sensing and analysis.
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Heavy metal ions (HMIs) seriously threaten human health even under trace conditions. Therefore, accurate, efficient and simultaneous detection of multiple HMIs is of great significance. Here, a strategy of "co-movement catalysis" based on photo-assisted electrochemical catalysis is proposed by constructing a flexible electrochemical sensor with CoFe2O4/CNS heterojunction-modified nickel foam as the working electrode for simultaneous detection of HMIs. Regarding photo-assisted catalysis, CoFe2O4/CNS nanocomposites formed a p-n type heterojunction, effectively separating photo-generated electron-hole pairs and reducing photo-generated carriers' recombination rate, leading to the catalytic reaction of photogenerated electrons and holes with HMIs and atoms to improve the efficiency of preconcentration and stripping, further amplifying the electrochemical signal. Regarding electrochemical catalysis, the CoFe2O4 spinel contains variable valence transition metal ions Fe2+/Fe3+ and Co2+/Co3+, which can reduce and oxidize HMIs circularly, further enhancing the sensor's sensitivity. The portable sensor based on "co-movement catalysis" exhibited sensitive detection performance. The linear range is 0.100-10.0 µM for Pb2+ and 1.00-10.0 µM for Cd2+, with the detection limit of 0.0310 µM for Pb2+ and 0.219 µM for Cd2+, respectively. The recovery rate of the sensor to natural water samples is between 96% and 105%, which proves its development potential in environmental monitoring.
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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.
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Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , DNA Circular , Prata , DNA/genética , Aptâmeros de Nucleotídeos/genética , Limite de DetecçãoRESUMO
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 Biossensoriais , Nanoestruturas , Imunoensaio , ÓxidosRESUMO
[This corrects the article DOI: 10.3892/ol.2018.8166.].
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An efficient photo-to-electrical signal is pivotal to photoelectrochemical (PEC) biosensors. In our work, a novel PEC biosensor was fabricated for the detection of neuron-specific enolase (NSE) based on a ZnIn2S4/Ag2CO3 Z-scheme heterostructure. Due to the overlapping band potentials of the ZnIn2S4 and Ag2CO3, the formed Z-scheme heterostructure can promote the charge separation and photoelectric conversion efficiency. And the concomitant Ag nanoparticles in Ag2CO3 provided multiple functions to enhance the PEC response of the Z-scheme heterostructure. It acts not only as a bridge for the transfer of carriers between ZnIn2S4 and Ag2CO3, promoting the constructed Z-scheme heterostructure, but also as electron mediators to accelerate the transfer of photogenerated carriers and improve the capture of visible light of the Z-scheme heterostructure by surface plasmon resonance (SPR). Compared with single Ag2CO3 and ZnIn2S4, the photocurrent of the designed Z-scheme heterostructure increased more than 20 and 60 times respectively. The fabricated PEC biosensor based on a ZnIn2S4/Ag2CO3 Z-scheme heterostructure exhibits sensitive detection to NSE, and presents a linear range of 50 fg·mL-1 ~ 200 ng·mL-1 with a limit of detection of 4.86 fg·mL-1. The proposed PEC biosensor provides a potential approach for clinical diagnosis.
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Técnicas Biossensoriais , Nanopartículas Metálicas , Nanopartículas Metálicas/química , Técnicas Eletroquímicas , Prata , Fosfopiruvato Hidratase , Limite de DetecçãoRESUMO
A novel multiple amplification strategy for electrochemical immunoassay was developed elaborately. The realization of this strategy is based on the high efficiency catalysis of boron nitrogen double-doped carbon loaded trimetallic PtPdCu mulberry-like nanospheres (PtPdCu/BNC) and the satisfactory conductivity of gold nanoparticles modified with sulfur nitrogen co-doped hollow porous carbon (Au@SNHC). Single crystal anisotropic Pt octahedral seeds were synthesized with sodium citrate as shape-directing agent, and then three metals were grown in situ to prepare the trimetallic PtPdCu mulberry nanospheres, which had excellent utilization of atoms and a significant number of catalytic active centers. Boron nitrogen double-doped carbon (BNC) with abundant free electrons and high electron density micro-mesoporous can be used as the supported dispersion material of PtPdCu MBNSs, further catalytically enrich H2O2. Moreover, the etching vulcanization of small ZIF template and the co-doping of sulfur and nitrogen endow sulfur nitrogen co-doped hollow porous carbon (SNHC) with shorter the diffusion distance of charge carrier and lower mass transfer resistance. Under optimal conditions, the developed immunosensor exhibits good sensing performance with a detection limit of 4.27 fgâ mL-1, and the wide linear dynamic range (10 fgâ mL-1-100 ngâ mL-1). This study provides a possible strategy for early diagnosis and postoperative monitoring of AMI.
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Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Nanopartículas Metálicas/química , Grafite/química , Troponina I , Ouro/química , Peróxido de Hidrogênio/química , Boro , Imunoensaio , Técnicas Eletroquímicas , Limite de Detecção , Anticorpos Imobilizados/química , Carbono , Nitrogênio , EnxofreRESUMO
A sandwich-type electrochemical immunosensor was designed by highly efficient catalytic cycle amplification strategy of CuFe2O4-Pd for sensitive detection of cardiac troponin I. CuFe2O4 with coupled variable valence metal elements exhibited favorable catalytic performance through bidirectional cycling of Fe2+/Fe3+ and Cu+/Cu2+ redox pairs. More importantly, Cu+ acted as the intermediate product of the catalytic reaction, promoted the regeneration of Fe2+ and ensured the continuous recycling occurrence of the double redox pairs, and significantly amplified the current signal response. Pd nanoparticles (Pd NPs) loaded on the surface of amino-functionalized CuFe2O4 (CuFe2O4-NH2) served as electrochemical mediators to capture labeled antibodies (Ab2), and also as co-catalysts of CuFe2O4 to further enhance the catalytic efficiency, thus improving the sensitivity of the electrochemical immunosensor. Under the optimal experimental conditions, the linear range was 0.001 ~ 100 ng/mL, and the detection limit was 1.91 fg/mL. The electrochemical immunosensor has excellent analytical performance, giving a new impetus for the sensitive detection of cTnI.
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Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Troponina I , Anticorpos Imobilizados , ImunoensaioRESUMO
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.
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Técnicas Biossensoriais , Estilbenos , Humanos , Lipossomos , Receptor ErbB-2 , Estilbenos/química , Técnicas Biossensoriais/métodos , Medições Luminescentes/métodos , Técnicas Eletroquímicas/métodos , Limite de DetecçãoRESUMO
In humans and animals, exposure to changes in internal or external environments causes acute stress, which changes sleep and enhances neurochemical, neuroendocrine, and sympathetic activities. Repeated stress responses play an essential role in the pathogenesis of psychiatric diseases and sleep disorders. However, the underlying mechanism of sleep changes and anxiety disorders in response to acute stress is not well established. In the current study, the effects of restraint stress (RS) on anxiety and sleep-wake cycles in mice were investigated. We found that after RS, the mice showed anxiety-like behavior after RS manipulation and increased the amounts of both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep in the dark period. The increase in sleep time was mainly due to the increased number of episodes of NREM and REM sleep during the dark period. In addition, the mice showed an elevation of the EEG power spectrum of both NREM and REM sleep 2 h after RS manipulation. There was a significant reduction in the EEG power spectrum of both NREM and REM sleep during the darkperiod in the RS condition. The expression of the c-Fos protein was significantly increased in the parabrachial nucleus, bed nucleus of the stria terminalis, central amygdala, and paraventricular hypothalamus by RS manipulation. Altogether, the findings from the present study indicated that neural circuits from the parabrachial nucleus might regulate anxiety and sleep responses to acute stress, and suggest a potential therapeutic target for RS induced anxiety and sleep alterations.
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Currently, the construction of heterojunctions as a method to enhance photoelectrochemical (PEC) activity has shown prospective applications in the analytical field. Restricted by carrier separation at the interface, developing a heterojunction sensing platform with high sensitivity remains challenging. Here, a double-photoelectrode PEC sensing platform was fabricated based on an antenna-like strategy by integrating MIL-68(In)-NH2, a p-type metal-organic framework (MOF) photocatalyst, as a photocathode with the type-II heterojunction of CdSe/MgIn2S4 as a photoanode synchronously. According to the ligand-to-metal charge transition (LMCT), the photo-generated carriers of MIL-68(In)-NH2 transferred from the organic ligand to the metal cluster, which provides an efficient antenna-like transfer path for the charge at the heterojunction interface. In addition, the sufficient Fermi energy difference between the double photoelectrode provides the continuous internal driving force required for rapid carrier separation at the anode detection interface, significantly improving the photoelectric conversion efficiency. Hence, compared with the traditional heterojunction single electrode, the photocurrent response of the double-photoelectrode PEC sensing platform developed using the antenna-like strategy is 2.5 times stronger. Based on this strategy, we constructed a PEC biosensor for the detection of programed death-ligand 1 (PD-L1). The elaborated PD-L1 biosensor exhibited sensitive and precise detection capability with a detection range of 1 × 10-5 to 1 × 103 ng/mL and a lower detection limit of 3.26 × 10-6 ng/mL and demonstrated the feasibility of serum sample detection, providing a novel and viable approach for the unmet clinical need of PD-L1 quantification. More importantly, the charge separation mechanism at the heterojunction interface proposed in this study provides new creative inspiration for designing sensors with high-sensitivity PEC performance.