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1.
Front Immunol ; 12: 737170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512671

RESUMO

Cerebral-cardiac syndrome (CCS) refers to cardiac dysfunction following varying brain injuries. Ischemic stroke is strongly evidenced to induce CCS characterizing as arrhythmia, myocardial damage, and heart failure. CCS is attributed to be the second leading cause of death in the post-stroke stage; however, the responsible mechanisms are obscure. Studies indicated the possible mechanisms including insular cortex injury, autonomic imbalance, catecholamine surge, immune response, and systemic inflammation. Of note, the characteristics of the stroke population reveal a common comorbidity with diabetes. The close and causative correlation of diabetes and stroke directs the involvement of diabetes in CCS. Nevertheless, the role of diabetes and its corresponding molecular mechanisms in CCS have not been clarified. Here we conclude the features of CCS and the potential role of diabetes in CCS. Diabetes drives establish a "primed" inflammatory microenvironment and further induces severe systemic inflammation after stroke. The boosted inflammation is suspected to provoke cardiac pathological changes and hence exacerbate CCS. Importantly, as the key element of inflammation, NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome is indicated to play an important role in diabetes, stroke, and the sequential CCS. Overall, we characterize the corresponding role of diabetes in CCS and speculate a link of NLRP3 inflammasome between them.

2.
ACS Appl Mater Interfaces ; 13(37): 44079-44085, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34514796

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) as traditional electrochemiluminescence (ECL) luminophores have been widely applied in the analysis field. However, their ECL intensity and efficiency are still limited due to the aggregation-induced quenching (ACQ) effect of PAHs. Hence, to overcome this limitation, we put forward a new strategy to increase the ECL intensity and efficiency by eliminating the ACQ effect of PAHs through the coordinative immobilization of PAHs within metal-organic frameworks (MOFs). As anticipated, the proof-of-concept experiment indicated that the coordinative immobilization of perylene-3,4,9,10-tetracarboxylate (PTC) into a Zn-PTC MOF could distinctly increase the ECL intensity and efficiency compared with H4PTC aggregates and H4PTC monomers. The reason for the ECL enhancement of Zn-PTC was that the immobilization of PTC within the MOF effectively amplified the distance between perylene rings of PTC ligands and thus eliminated the ACQ effect. Furthermore, the PTC into Zn-PTC was stacked in an edge-to-edge mode to form J-aggregation, which was also conducive to ECL enhancement. On the basis of the excellent ECL performance, we utilized Zn-PTC as a new ECL emitter combined with exonuclease III-stimulated target cycling and DNAzyme-assisted cycling dual amplification strategies to construct an ECL sensor for microRNA-21 detection, which had a wide signal response (100 aM to 100 pM) with a detection limit of 29.5 aM. Overall, this work represents a new and convenient method to overcome the ACQ effect of PAHs and boost the ECL performance, which opens a new horizon for developing high-performance ECL materials, thus offering more opportunities for building highly sensitive ECL biosensors.

3.
Biosens Bioelectron ; 190: 113446, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34166945

RESUMO

The inevitable nonspecific recognition severely restricted widely used nucleic acid amplification strategies, which has become an urgent problem in current scientific research. Herein, we developed a novel no-nonspecific recognition-based amplification strategy to construct dual-color dye loaded nano-clew as ultrabright illuminant for screening endonuclease activity with Escherichia coliRY13 I (EcoR I) as a model, which overcame some major drawbacks such as nonspecific recognition and photobleaching. Typically, the target endonuclease induces cleavage of the customized dumbbell-shape substrate (DSS) to generate two same triggers that can initiate the rolling circle amplification (RCA) to prepare long single-strand DNA (lssDNA), which could self-assemble into irregular DNA nano-clew based on the electrostatic interactions with Mg2+ to furtherly capture the donor and accepter fluorophore proximately, constructing the dye loaded nano-clew with dual-color fluorescence (FL) emission to resist photobleaching. Importantly, in absence of EcoR I, even if the DSS could combine with circular template a little, the reaction system performed hardly RCA reaction due to no cohesive terminus, resulting an extremely low background fluorescence signal because of the prevention of nonspecific RCA reaction. As expected, the proposed sensing platform with a low limit of detection (LOD) of 3.4 × 10-7 U/µL was demonstrated to work well for endonuclease inhibitors screening also. Furthermore, the proposed no-nonspecific recognition strategy could be readily extended to various DNA or RNA enzymes such as DNA methyltransferase, DNA repair-related enzymes and polynucleotide kinase just by simply changing the recognition sequence in the DNA substrate, performing great potential of endonucleases-related clinical diagnosis and drugs discovery.


Assuntos
Técnicas Biossensoriais , DNA/genética , Endonucleases , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico
4.
Chem Commun (Camb) ; 57(35): 4323-4326, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33913953

RESUMO

A facile strategy to design a highly efficient electrochemiluminescence resonance energy transfer (ECL-RET) system was proposed by using an AIEgen-based 2D ultrathin metal-organic layer (MOL) to coordinatively immobilize energy donors and acceptors simultaneously, in which the distance between adjacent donor-acceptor pairs was precise and short for obtaining high ECL-RET efficiency.


Assuntos
Técnicas Eletroquímicas , Transferência Ressonante de Energia de Fluorescência , Estruturas Metalorgânicas/química , Trombina/análise , Estrutura Molecular , Tamanho da Partícula , Trombina/metabolismo
5.
Anal Chem ; 93(15): 6239-6245, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33822576

RESUMO

Metal-organic frameworks (MOFs) with porous structures exhibit favorable promise in synthesizing high-performance electrochemiluminescence (ECL) materials, yet their micropores and narrow channels not only restrict the loading capacity of ECL luminophores but also constrain the diffusion of coreactants, ions, and electrons. Hence, we developed a new and simple hydrothermal etching strategy for the fabrication of a hollow hierarchical MOF (HH-UiO-66-NH2) with a hierarchical-pore shell, which was employed as a carrier to graft Ru(bpy)2(mcpbpy)2+ (bpy = 2,2'-bipyridine, mcpbpy = 4-(4'-methyl-[2,2'-bipyridin]-4-yl) butanoic acid) onto the coordinatively unsaturated Zr6 nodes of HH-UiO-66-NH2, creating the Ru-complex-grafted HH-UiO-66-NH2 (abbreviated as HH-Ru-UiO-66-NH2). Impressively, the HH-Ru-UiO-66-NH2 presented brilliant ECL emission. On the one hand, the HH-UiO-66-NH2 with a hierarchical-pore shell and hollow cavity was conducive to immobilize the Ru(bpy)2(mcpbpy)2+ of large steric hindrance into the interior of the MOF, markedly improving the load number of luminophores. On the other hand, the hierarchical-pore shell of HH-UiO-66-NH2 permitted fast diffusion of coreactants, ions, and electrons that facilitated the excitation of more grafted luminophores and greatly enhanced the utilization ratio of ECL luminophores. Inspired by the superior ECL performance of HH-Ru-UiO-66-NH2, an ECL sensing platform was constructed on the basis of HH-Ru-UiO-66-NH2 as an ECL beacon combining catalytic hairpin assembly as a signal amplification strategy, showing excellent selectivity and high sensitivity for thrombin determination. This proof-of-concept work proposed a simple and feasible hydrothermal etching strategy to construct hollow hierarchical MOFs that served as carrier materials to immobilize ECL luminophores, providing significant inspiration to develop highly efficient ECL materials and endowing hollow hierarchical MOFs with ECL sensing applications for the first time.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , Rutênio , Técnicas Eletroquímicas , Medições Luminescentes , Trombina
6.
Anal Chem ; 93(6): 3258-3265, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33529534

RESUMO

A pyrene-based sp2 carbon-conjugated covalent organic framework (COF) nanosheet (Py-sp2c-CON) with strong and stable electrochemiluminescence (ECL) emission was constructed by C═C polycondensation of tetrakis(4-formylphenyl)pyrene (TFPPy) and 2,2'-(1,4-phenylene)diacetonitrile, which was employed as a highly efficient ECL emitter to fabricate an ECL biosensor for the first time. The Py-sp2c-CON exhibited higher ECL intensity and efficiency than those of TFPPy, bulk Py-sp2c-COF, and imine-linked pyrene COF, not only because the pyrene luminophores and aggregation-induced emissive luminogens (cyano-substituted phenylenevinylene) were topologically linked into Py-sp2c-CON, which greatly increased the immobilization amount of luminophores and decreased the aggregation-caused quenching effect and nonradiative transition but also because the porous ultrathin structure of Py-sp2c-CON effectively shortened transport distances of an electron, ion, and co-reactant (S2O82-), which made more ECL luminophores be activated and thus efficiently increased the utilization ratio of luminophores. More interestingly, when Bu4NPF6 was introduced into the Py-sp2c-CON/S2O82- system as a co-reaction accelerator, the ECL signal of Py-sp2c-CON was further amplified. As expected, the average ECL intensity of the Py-sp2c-CON/S2O82-/Bu4NPF6 system was about 2.03, 5.76, 24.31, and 190.33-fold higher than those of Py-sp2c-CON/S2O82-, Py-sp2c-COF/S2O82-, TFPPy/S2O82,- and imine-linked pyrene COF/S2O82- systems. Considering these advantages, the Py-sp2c-CON/S2O82-/Bu4NPF6 system was employed to prepare an ECL biosensor for microRNA-21 detection, which exhibited a broad linear response (100 aM to 1 nM) and a low detection limit (46 aM). Overall, this work demonstrated that sp2 carbon CONs can be directly used as a high-performance ECL emitter, thus expanding the application scope of COFs and opening a new horizon to develop new types of ECL emitters.


Assuntos
Técnicas Biossensoriais , Estruturas Metalorgânicas , MicroRNAs , Técnicas Eletroquímicas , Medições Luminescentes
7.
Anal Chem ; 93(3): 1834-1841, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33389990

RESUMO

Two-dimensional (2D) nanosheets have captured significant attention in constructing highly efficient electrochemiluminescent (ECL) materials because their high surface area and fully exposed postmodification sites could greatly increase the loading amount of luminophores. However, traditional 2D nanosheets as carriers exhibited natively poor electrical conductivity that restricted the electrochemical activation and the utilization ratio of ECL luminophores. Herein, to overcome this drawback, we utilized conductive 2D Ti3C2Tx MXene nanosheets as carriers to graft Ru(bpy)2(mcpbpy)2+ (bpy = 2,2'-bipyridine, mcpbpy = 4-(4'-methyl-[2,2'-bipyridin]-4-yl) butanoic acid) via a dehydrative condensation reaction and electrostatic interaction. Interestingly, Ru(bpy)2(mcpbpy)2+ played the role of "two birds with one stone", where Ru(bpy)2(mcpbpy)2+ acted as both an ECL luminophore and an intercalation molecule to achieve surface functionalization and delamination of multilayered Ti3C2Tx successfully, obtaining 2D ultrathin Ru-complex-grafted MXene nanosheets (Ru@MXene). Owing to the high load capacity and superior electrical conductivity of an ultrathin 2D MXene nanosheet, the obtained Ru@MXene exhibited a superb ECL emission. As expected, compared with the nonconductive 2D ultrathin metal-organic layers (MOLs) as carriers to graft Ru(bpy)2(mcpbpy)2+, the ECL intensity and ECL efficiency of Ru@MXene presented about 5-fold and 1.7-fold enhancement, respectively. Considering these advantages, Ru@MXene was applied to construct an ECL sensor for ultrasensitive determination of mucin 1 (MUC1), which displayed superb sensitivity (100 ag/mL to 10 ng/mL) with a low detection limit of 26.9 ag/mL. Overall, the conductivity-enhanced ECL based on Ru@MXene opened a fire-new chapter to develop splendent performance ECL emitters and shed new light on the application potential of conductive materials in the bioanalysis field.

8.
Anal Chem ; 92(22): 15120-15128, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33104338

RESUMO

Considering the central challenge of the simple and efficient strategy to generate sensitive analysis technology, herein, we proposed a novel electrochemiluminescence (ECL) strategy based on target-induced self-enrichment via hydrophobic interaction to generate significant ECL enhancement for untrasensitive detection of clinical biomarkers with cardiac troponin I (cTnI) for early diagnosis of acute myocardial infarction (AMI) as a model. Typically, the first antibody of cTnI (fAb) was immobilized onto the as-prepared electrode surface with the titanium dioxide nanoflower and gold nanoclusters When there was target cTnI, it could be captured onto the electrode surface based on the specific antigen-antibody interaction to furtherly capture cholesterol-modified second antibody of cTnI to increase the hydrophobicity of the electrode surface, which could be employed for the self-enrichment of hydrophobic ECL luminophore, tris(2,2'-bipyridyl-4,4'-dicarboxylato) ruthenium(II), and coreactant, tripropylamine in the detection solution. Thus, an increased ECL emission could be achieved due to the increased concentration of ECL luminophore and coreactant, which was quantitatively related with the concentration of target cTnI. As expected, a higher sensitivity was obtained with a detection limit of 0.04 pg/mL based on simplest operations of the proposed strategy with target-induced self-enrichment via hydrophobic interaction. Importantly, this hydrophobic interaction-based ECL strategy could be easily expanded to the bioassay of various biomarkers, providing an efficient tool for early clinical diagnosis of AMI and some other diseases.


Assuntos
Técnicas Biossensoriais/métodos , Interações Hidrofóbicas e Hidrofílicas , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química
9.
Chem Commun (Camb) ; 56(70): 10215-10218, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32748935

RESUMO

In this work, a novel DNA nanostructure with a shorter assembly time and larger loading capacity was constructed using amphiphilic DNA-alkane group (Spacer C12)10 conjugates encapsulating plentiful fat-soluble fluorescent dyes into the hydrophobic core to form the DNA micelles, which could be rapidly self-disassembled via target induced hydrophilic-hydrophobic regulation to release fluorescent dyes from micelles to the organic phase, realizing the fast and sensitive detection of microRNA.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , Interações Hidrofóbicas e Hidrofílicas , Micelas , MicroRNAs/análise , Polímeros/química , Alcanos/química , Fatores de Tempo
10.
Anal Chim Acta ; 1126: 24-30, 2020 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-32736721

RESUMO

Herein, an orbitron-like three-dimensional (3D) DNA clip-based nanomachine was proposed for ultrasensitive fluorescent bioassay of microRNA, which was constructed by mechanically interlocking double-DNA-ring with two single-stranded DNAs, performing an orbitron-like 3D structure with double freely rotated DNA rings as the open state. In the presence of target microRNA, the proposed orbitron-like 3D DNA clip can alter its structure from open to closed state in identification of the target microRNA, generating the closure between the previously modified fluorescent dyes and the quenchers to perform a "signal off" fluorescent signal correlated with the concentration of target microRNA. Compared with the normal DNA nanomachines, such as DNA tweezers constructed by self-assembly of three single-stranded DNAs which regulated the open and closed states on the basis of linear conformational changes, the proposed 3D DNA clip-based nanomachine with high mechanical rigidity realized the conformational changes in 3D space with the assistance of target microRNA, which could effectively increase the adjustable distance range and reduce the background signal. Furthermore, the 3D DNA clip-based nanomachine was applied in the fluorescent detection of microRNA-21 with favorable performances for the sensitive detection of microRNA in cells, providing a new avenue for early clinical diagnoses of disease.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Bioensaio , DNA/genética , MicroRNAs/genética , Instrumentos Cirúrgicos
11.
Neurosci Bull ; 36(9): 1035-1045, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32683554

RESUMO

Ischemic stroke is one of the leading causes of death worldwide. In the post-stroke stage, cardiac dysfunction is common and is known as the brain-heart interaction. Diabetes mellitus worsens the post-stroke outcome. Stroke-induced systemic inflammation is the major causative factor for the sequential complications, but the mechanism underlying the brain-heart interaction in diabetes has not been clarified. The NLRP3 (NLR pyrin domain-containing 3) inflammasome, an important component of the inflammation after stroke, is mainly activated in M1-polarized macrophages. In this study, we found that the cardiac dysfunction induced by ischemic stroke is more severe in a mouse model of type 2 diabetes. Meanwhile, M1-polarized macrophage infiltration and NLRP3 inflammasome activation increased in the cardiac ventricle after diabetic stroke. Importantly, the NLRP3 inflammasome inhibitor CY-09 restored cardiac function, indicating that the M1-polarized macrophage-NLRP3 inflammasome activation is a pathway underlying the brain-heart interaction after diabetic stroke.


Assuntos
Diabetes Mellitus Tipo 2 , Cardiopatias , Inflamassomos , AVC Isquêmico , Macrófagos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2/complicações , Cardiopatias/etiologia , AVC Isquêmico/complicações , Camundongos
12.
Chem Commun (Camb) ; 56(60): 8488-8491, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32588858

RESUMO

Here, a near-infrared (NIR) light-controlled, ultrasensitive one-step photoelectrochemical (PEC) strategy was constructed to simultaneously detect cell apoptosis indicators, phosphatidylserine (Pho) and sodium-potassium adenosine triphosphatase (Sat), on living cancer cells. Using NIR light as excitation, the signal probe methylene blue (Tagkinetic) could be released, leading to a gradually decreased photocurrent signal Ikinetic; meanwhile, the photocurrent Istable of the signal probe carbon quantum dots (Tagstable) remained stable. The simultaneous detection of Pho and Sat could be achieved based on rapid one-step PEC detection under single NIR light with the assistance of a smart signal decryption strategy with Ikinetic and Istable. Importantly, this proposal provides more effective drug candidates with milder pharmaceutical effect but improved safety.


Assuntos
Apoptose , Técnicas Eletroquímicas/métodos , Raios Infravermelhos , Fosfatidilserinas/análise , ATPase Trocadora de Sódio-Potássio/análise , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Humanos , Cinética , Azul de Metileno/química , Microscopia Confocal , Pontos Quânticos/química
13.
Nanoscale ; 12(10): 5932-5941, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32108836

RESUMO

In this work, a novel two-dimensional (2D) ultrathin metal-organic layer (MOL) based on the aggregation-induced emission (AIE) ligand H4ETTC (H4ETTC = 4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(([1,1'-biphenyl]-4-carboxylic acid))) was developed and used to construct a novel electrochemiluminescence (ECL) aptasensor for ultrasensitive detection of carcinoembryonic antigen (CEA). The newly synthesized AIE luminogen (AIEgen)-based MOL (Hf-ETTC-MOL) yielded a higher ECL intensity and efficiency than did H4ETTC monomers, H4ETTC aggregates and 3D bulk Hf-ETTC-MOF. This improvement occurred not only because the ETTC ligands were coordinatively immobilized in a rigid MOL matrix, which restricted the intramolecular free rotation and vibration of these ligands and then reduced the non-radiative transition, but also because the porous ultrathin 2D MOL greatly shortened the transport distances of ions, electrons, coreactant (triethylamine, TEA) and coreactant intermediates (TEA˙ and TEA˙+), which made more ETTC luminophores able to be excited and yielded a high ECL efficiency. On the basis of using the Hf-ETTC-MOL as a novel ECL emitter and rolling circle amplification (RCA) as a signal amplification strategy, the constructed ECL aptasensor exhibited a linear range from 1 fg mL-1 to 1 ng mL-1 with a detection limit of 0.63 fg mL-1. This work has opened up new prospects for developing novel ECL materials and is expected to lead to increased interest in using AIEgen-based MOLs for ECL sensing.


Assuntos
Técnicas Biossensoriais , Antígeno Carcinoembrionário/análise , Técnicas Eletroquímicas , Medições Luminescentes , Proteínas Ligadas por GPI/análise , Humanos
14.
Biosens Bioelectron ; 155: 112099, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32090871

RESUMO

Herein, a new phenomenon of enhanced electrochemiluminescence (ECL) emission by restricting intramolecular motion in the 2D ultra-thin Zr12-adb (adb = 9,10-anthracene dibenzoate) metal-organic framework (MOF) nanoplate was discovered for the first time. The coordination immobilization of adb in porous ultra-thin Zr12-adb nanoplate endowed the Zr12-adb excellent ECL performance, including stronger ECL signal and higher ECL efficiency relative to those of H2adb monomers and H2adb aggregates. In the 2D Zr12-adb nanoplate, the bridging ligand adb was stretched and fixed between two Zr12 clusters, which restricted intramolecular rotations and suppressed unnecessary energy loss caused by self-rotation, thereby remarkably improved the ECL intensity and efficiency. More importantly, the porous ultra-thin structure of Zr12-adb MOF nanoplate not only allowed the coreactants to diffuse into the MOF interior, making both internal and external adb be excited, but also shortened the migration distance of electrons, ions, coreactants and coreactant intermediates, which further improved the ECL efficiency of Zr12-adb and overcame the shortcoming of H2adb aggregates in which the internal luminophores were not easily excited. Regarding the excellent ECL properties above, Zr12-adb nanoplate was selected as a new ECL emitter incorporated with the bipedal walking molecular machine together to fabricate a biosensor for sensitive detection of mucin 1. The enhanced ECL by restriction of intramolecular motions in MOFs provided a new pathway to improve ECL intensity and efficiency, which lighted up a lamp for the design and manufacture of high-performance ECL materials based on MOFs, thus offering new opportunities to develop ultrasensitive ECL biosensors.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Medições Luminescentes , Estruturas Metalorgânicas/química , Fenômenos Químicos , Humanos , Estruturas Metalorgânicas/ultraestrutura , Mucina-1/sangue , Nanoestruturas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise Espectral
15.
Chemistry ; 26(40): 8767-8773, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32060953

RESUMO

The evident contradiction between high local-concentration-based substrate reactivity and free-diffusion-based high reaction efficiency remains one of the important challenges in chemistry. Herein, we propose an efficient aggregation-induced synergism through the hydrophobic-driven self-assembly of amphiphilic oligonucleotides to generate high local concentration whereas retaining high reaction efficiency through hydrophobic-based aggregation, which is important for constructing efficient DNA nanomachines for ultrasensitive applications. MicroRNA-155, used as a model, triggered strand displacement amplification of the DNA monomers on the periphery of the 3D DNA nanomachine and generated an amplified fluorescent response for its sensitive assay. The local concentration of substrates was increased by a factor of at least 9.0×105 through hydrophobic-interaction-based self-assembly in comparison with the traditional homogeneous reaction system, achieving high local-concentration-based reactivity and free-diffusion-based enhanced reaction efficiency. As expected, the aggregation-induced synergism by hydrophobic-driven self-assembly of amphiphilic oligonucleotides created excellent properties to generate a 3D DNA nanomachine with potential as an assay for microRNA-155 in cells. Most importantly, this approach can be easily expanded for the bioassay of various biomarkers, such as nucleotides, proteins, and cells, offering a new avenue for simple and efficient applications in bioanalysis and clinical diagnosis.


Assuntos
DNA/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Oligonucleotídeos/química , Proteínas/genética , DNA/genética , Difusão , Interações Hidrofóbicas e Hidrofílicas , Proteínas/química
16.
Anal Chem ; 92(3): 2566-2572, 2020 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-31922394

RESUMO

We hereby described an electrochemiluminescence (ECL) biosensor for glutathione (GSH) based on a 3D DNA matrix with ordered binding sites and cavity structure that self-assembled from tetrahedral DNA blocks (TDBs). First, the alkyne-labeled TDBs were employed to build an alkyne-rich 3D matrix (C≡C-3DM) on the electrode surface. Then, the GSH-induced click chemistry was triggered as a signal switch to introduce the large amounts of N3-DNA decorated AuAg nanoclusters (N3-AuAg NCs) into C≡C-3DM for signal output. In particular, the presence of GSH could induce the formation of GSH-Cu(I) complex by the redox reaction between GSH and Cu(II), which could act as an initiator to link the N3-AuAg NCs with C≡C-3DM according to the Huisgen 1,3-dipolar cycloaddition reaction. By this way, numerous N3-AuAg NCs were orderly bonded to the 3D matrix to effectively reduce their agglomeration and inner filter effect, achieving a remarkable ECL enhancement. As a result, the proposed GSH biosensor showed a wide linear range from 5 to 200 µM with a low detection limit of 0.90 µM. In general, this work provided a rapid, highly efficient, and convenient signal amplification for small-molecule detection and broadened the application of TDBs in biosensing.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Glutationa/análise , Ouro/química , Medições Luminescentes , Nanopartículas Metálicas/química , Prata/química , Química Click , DNA/química , Tamanho da Partícula , Propriedades de Superfície
17.
Anal Chem ; 92(4): 3380-3387, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31967795

RESUMO

Here, we discovered that rigidifying the tetraphenylethylene (TPE)-based ligand H4TCBPE (H4TCBPE = 1,1,2,2-tetra(4-carboxylbiphenyl)ethylene) into Hf-based metal-organic framework (Hf-TCBPE) could lead to a stronger electrochemiluminescence (ECL) emission in comparison to H4TCBPE aggregates and H4TCBPE monomers. Due to the lack of close-packed TCBPE chromophores in Hf-TCBPE, which was required for aggregation-induced ECL (AI-ECL) enhancement, we defined this unprecedented phenomenon as matrix coordination-induced ECL (MCI-ECL) enhancement. The strong ECL intensity of Hf-TCBPE not only originated from the fixation of the TCBPE ligand between Hf6 clusters that restricted the intramolecular free motions of TCBPE and suppressed the nonradiative relaxation but also stemmed from the high porosity of Hf-TCBPE that rendered both internal and external TCBPE chromophores able to be excited. Considering the unique ECL characteristic of Hf-TCBPE, we combined the new ECL indicator of Hf-TCBPE as well as the phosphate-terminal ferrocene (Fc)-labeled hairpin DNA (Fc-HP3) aptamer together as a signal probe (Hf-TCBPE/Fc-HP3), which was employed to construct a novel "off-on" ECL sensor for ultrasensitive mucin 1 (MUC1) detection with the assistance of the exonuclease III (Exo III)-assisted recycling amplification strategy. As expected, the ECL sensor displayed a desirable linear response range from 1 fg/mL to 1 ng/mL and the detection limit down to 0.49 fg/mL. The MCI-ECL enhancement demonstrated by the Hf-TCBPE developed a new and promising strategy to design and synthesize high-performance metal-organic framework (MOF)-based ECL materials for constructing ultrasensitive ECL sensors.

18.
Chem Sci ; 11(21): 5410-5414, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-34094067

RESUMO

Electrochemiluminescence (ECL) micro-reactors with enhanced intensity and extreme stability were first established by the assembly of tris(2,2'-bipyridyl) ruthenium(ii) (Ru(bpy)3 2+) onto covalent organic frameworks (COFs), in which a type of imine-linked COF (denoted as COF-LZU1) was employed as a model for ECL micro-reactors. Compared with the dominant ECL system of Ru(bpy)3 2+/tri-n-propylamine (TPrA) (TPrA as a co-reactant), the intensity of the COF-LZU1 micro-reactor-based electrode was significantly increased nearly 5-fold under the same experimental conditions, which is unprecedented in other Ru(bpy)3 2+-based ECL systems. This enhancement can be attributed to the large surface area, delimited space, and stable and hydrophobic porous structure of COF-LZU1, which not only enabled a huge amount of Ru(bpy)3 2+ to be loaded in/on COF-LZU1, but also enriched a large amount of TPrA from the aqueous solution into its inner hydrophobic cavity due to the lipophilicity of TPrA. More importantly, with its hydrophobic porous nanochannels, COF-LZU1 could act as micro-reactors to provide a delimited reaction micro-environment for the electrochemical oxidation of TPrA and the survival of TPrA˙, achieving significant confinement-enhanced ECL. To prove this principle, these Ru@COF-LZU1 micro-reactors were developed to prepare an ECL aptasensor for aflatoxin M1 (AFM1) detection with a wide detection range and a low detection limit. Overall, this work is the first report in which ECL micro-reactors are constructed with COFs to enhance the intensity and stability of the Ru(bpy)3 2+-based ECL system, and opens a new route to the design of other ECL micro-reactors for bioanalysis applications.

19.
Anal Chem ; 91(23): 14920-14926, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31674756

RESUMO

Herein, a novel three-dimensional (3D) DNA nanomachine with high walking efficiency via free DNA walker movement on biomimetic lipid bilayers supported by hard silica@CdTe quantum dots (SiO2@CdTe) was constructed for ultrasensitive fluorescence detection of microRNA. The synthesized SiO2@CdTe nanoparticles were adopted as the fluorescence indicator and spherical carrier of lipid bilayers, and then the DNA substrates were anchored on lipid bilayers with biomimetic fluidity through the cholesterol-lipid interaction. Once target microRNA-141 interacted with the 3D DNA nanomachine to release cholesterol labeled arm (Chol-arm), the Chol-arm could generate a series of strand displacement reactions by moving freely on the lipid bilayers, resulting in the releasement of numerous quenchers from the SiO2@CdTe nanoparticles and inducing a strong fluorescence signal. Impressively, compared with traditional 3D DNA nanomachine conjugating DNA substrates on hard surfaces (such as gold or silica) with limited reactivity, the proposed biomimetic 3D DNA nanomachine not only immobilized DNA substrates rapidly and effectively but also kept it with a favorable fluidity, which significantly enhanced the walking efficiency. As expected, the biomimetic 3D DNA nanomachine for fluorescence detection of microRNA-141 exhibited an excellent performance with a detection limit of 0.21 pM and presented promising properties in cell lysate detection and intracellular imaging. Thus, the described biomimetic 3D DNA nanomachine provided a novel avenue for sensitive detection of biomolecules, which could be useful for bioanalysis and early clinical diagnoses of disease.


Assuntos
Materiais Biomiméticos/química , Técnicas Biossensoriais , Compostos de Cádmio/química , Ácidos Nucleicos Imobilizados/química , Bicamadas Lipídicas/química , MicroRNAs/análise , Telúrio/química , Linhagem Celular Tumoral , Colesterol/química , Feminino , Humanos , Limite de Detecção , Células MCF-7 , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , MicroRNAs/genética , MicroRNAs/metabolismo , Microscopia de Fluorescência , Nanotecnologia/métodos , Pontos Quânticos/química , Dióxido de Silício/química
20.
Chem Commun (Camb) ; 55(89): 13414-13417, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31638106

RESUMO

Herein, by anchoring cholesterol-labelled DNA probes to silicon-supported lipid bilayers via cholesterol-lipid interaction, a dynamic three-dimensional (3D) DNA nanostructure could be facilely assembled, which is applied as a microRNA (miRNA)-induced self-powered 3D DNA nanomachine with high movement efficiency. Once the self-powered 3D DNA nanomachine is triggered by target miRNA, it achieves autonomous operation without external addition of fuel DNA strands or protein enzymes. Impressively, the biocompatible lipid bilayers not only preserve the biological character of the DNA probes, but also improve the movement efficiency of the DNA nanomachine, which directly solves the key challenge of the steric barrier effect of traditional rigid surfaces (Au or silicon) for DNA probe diffusion. As a proof of concept, our proposed DNA nanomachine is successfully applied in rapid and sensitive detection of miRNAs, which gives a new idea for the construction of highly efficient DNA nanomachines for biosensing and clinic diagnosis.


Assuntos
Técnicas Biossensoriais , DNA/química , Bicamadas Lipídicas/química , Nanoestruturas/química , Silício/química , Colesterol/química , Sondas de DNA/química , Técnicas e Procedimentos Diagnósticos , Células HeLa , Humanos , Células MCF-7 , MicroRNAs/análise , MicroRNAs/química , Microscopia Confocal , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície
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