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1.
Anal Chem ; 96(15): 5852-5859, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38556977

RESUMO

A multicolor electrochemiluminescence (ECL) biosensor based on a closed bipolar electrode (BPE) array was proposed for the rapid and intuitive analysis of three prostate cancer staging indicators. First, [Irpic-OMe], [Ir(ppy)2(acac)], and [Ru(bpy)3]2+ were applied as blue, green, and red ECL emitters, respectively, whose mixed ECL emission colors covered the whole visible region by varying the applied voltages. Afterward, we designed a simple Mg2+-dependent DNAzyme (MNAzyme)-driven tripedal DNA walker (TD walker) to release three output DNAs. Immediately after, three output DNAs were added to the cathodic reservoirs of the BPE for incubation. After that, we found that the emission colors from the anode of the BPE changed as a driving voltage of 8.0 V was applied, mainly due to changes in the interfacial potential and faradaic currents at the two poles of the BPE. Via optimization of the experimental parameters, cutoff values of such three indicators at different clinical stages could be identified instantly with the naked eye, and standard precision swatches with multiple indicators could be prepared. Finally, in order to precisely determine the prostate cancer stage, the multicolor ECL device was used for clinical analysis, and the resulting images were then compared with standard swatches, laying the way for accurate prostate cancer therapy.


Assuntos
Técnicas Biossensoriais , Neoplasias da Próstata , Masculino , Humanos , Medições Luminescentes/métodos , Fotometria , Neoplasias da Próstata/diagnóstico , Antígeno Prostático Específico , DNA , Técnicas Biossensoriais/métodos , Eletrodos , Técnicas Eletroquímicas/métodos
2.
Anal Chem ; 94(10): 4303-4310, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35230810

RESUMO

In this work, a new electrochemiluminescence (ECL) platform was constructed for detecting the prostate cancer marker microRNA-141 (miRNA-141) on a constant resistor-integrated closed bipolar electrode (BPE). It consisted of two reservoirs and a constant resistor, and both ends were connected to the anode of the driving electrode and the cathode of BPE. The cathode of BPE was modified with boron nitride quantum dots (BNQDs), and the anode reservoir was the [Ru(bpy)3](PF6)2/TPrA system. After introducing a certain amount of hairpin DNA 3 (H3) and ferrocene-labeled single-stranded DNA (Fc-ssDNA) on the surface of the BNQDs, the ECL emission signal of the BNQDs was difficult to be observed by the naked eye, while [Ru(bpy)3](PF6)2 emitted a strong and visible ECL signal. In the presence of the target, bipedal DNA assembled by catalytic hairpin assembly (CHA) took away the Fc-ssDNA and the ECL intensity of the BNQDs was enlarged, and as the concentration of miRNA-141 increased to the cutoff value, yellow-green light was visible by the naked eye. Meanwhile, the red emission signal of [Ru(bpy)3](PF6)2/TPrA became weakened. Thus, an ultrasensitive "color switch" ECL biosensor for detection of miRNA-141 was constructed and endowed with a wide linear range from 10-17 to 10-7 M and a detection limit of 10-17 M (S/N = 3). This study provides the potential for investigating portable devices in the detection of low-concentration nucleic acids.


Assuntos
Técnicas Biossensoriais , MicroRNAs , DNA , Técnicas Eletroquímicas , Eletrodos , Medições Luminescentes , MicroRNAs/análise
3.
Anal Chem ; 90(5): 3570-3575, 2018 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-29417820

RESUMO

A selective excitation of [Ir(df-ppy)2(pic)] and [Ru(bpy)3]2+ through tuning the electrode potential is reported in this work. Bidirectional color change from blue-green to red could be observed along with increase and decrease of the potential, which was ascribed to the dual-potential excitation property of [Ir(df-ppy)2(pic)]. Similar to the three-electrode system, selective excitation of ECL could be achieved at the anode of the bipolar electrode (BPE). Both increase and decrease of the faradic reactions at the cathode of the BPE could induce ECL reporting color at the other pole switched from blue-green to red. We applied a closed BPE device for the bioanalysis of multicolor ECL since the organic solvent containing electrochemiluminophores could be separated from the bioanalytes. On the basis of BPE arrays coupled with the ECL switch, the detection of three biomarkers of prostate cancer, PSA, microRNA-141, and sarcosine were integrated in a same device. The cutoff values of the biomarkers could be recognized directly by the naked eye. Such a device holds great potential in the early diagnosis of prostate cancer.


Assuntos
Substâncias Luminescentes/química , Medições Luminescentes/métodos , MicroRNAs/sangue , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/urina , Sarcosina/urina , 2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/química , Animais , Aptâmeros de Nucleotídeos/química , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina , Técnicas Biossensoriais/métodos , Colorimetria/métodos , Eletrodos , Cavalos , Humanos , Irídio/química , Masculino , Compostos Organometálicos/química
4.
Anal Chem ; 89(15): 8050-8056, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28660761

RESUMO

We report a multicolor ECL device based on closed bipolar electrode (BPE) for the visualized sensing of prostate-specific antigen (PSA) in human blood serum. As the emission color of concomitant electrochemiluminophores is potential resolved, similar to a three-electrode system, selective excitation of ECL could be achieved by tuning the interfacial potential at the poles of BPE. Via modulating the resistance of BPE, multicolor ECL emission of [Ru(bpy)3]2+ and [Ir(ppy)3] mixture using tripropylamine (TPrA) as the co-reactant was observed at the anode and the principle was elaborated. The concept was utilized to the quantification of clinical biomarkers with the color variation. A PSA concentration dependent silver bridge was constructed in the gap of the BPEs as an electric conductivity modulator. On the basis of a multicolor BPE-ECL device, the cutoff values (4.0 and 10.0 ng/mL) of human PSA could be recognized with naked eyes by the green-yellow-red ECL emission changing. As the first multicolor ECL device in biological analysis, BPE may raise the application of potential-resolved ECL to a new level.


Assuntos
Técnicas Biossensoriais/métodos , Medições Luminescentes/métodos , Antígeno Prostático Específico/sangue , Complexos de Coordenação/química , Técnicas Eletroquímicas , Eletrodos , Humanos , Compostos Organometálicos/química , Propilaminas/química
5.
Biosens Bioelectron ; 86: 683-689, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27472402

RESUMO

Herein, a spatial-resolved electrochemiluminescene (ECL) ratiometry based on a closed biopolar electrode (BPE) is reported for the highly sensitive detection of prostate specific antigen (PSA). Au@g-C3N4 NCs as one ECL emitter were firstly coated on the cathode of BPE, while the anode of the BPE served for calibration via another ECL substance, Ru(bpy)3(2+). The electroneutrality across the BPE makes the reactions on each pole of BPE electrically coupled. Thus one electrochemical sensing reaction at one pole of BPE could be quantified at both ends. A composite, Pt-PAMAM-DNAzyme was assembled on the surface of cathode via DNA hybridization between probe DNA and PSA aptamer. It acted as an ECL quencher of g-C3N4 via resonance energy transfer (RET) and catalyzing the reduction of O2, the co-reactant of g-C3N4. Meanwhile, it could promote the ECL of Ru(bpy)3(2+) at anode, since the catalytic reduction of O2 at the cathode increased the faradiac current flowing through the BPE. Based on this signal composite, an ECL "off-on" phenomenon was observed at the cathode, after Pt-PAMAM-DNAzyme was "peeled off" by PSA. Conversely, at the anode, an "on-off" ECL changing was obtained. Therefore, a sensitive ratiometry for PSA detection was achieved with a linear range from 0.10 to 200ng/mL. Since the two ECL emitters were physically separated, the ratiometric system was relatively simple and neither optical filters nor spectrometer were required. The strategy combining the ECL ratiometry and BPE broadens the applications of BPE-ECL and shows good perspective in clinical application.


Assuntos
Técnicas Biossensoriais/instrumentação , Condutometria/instrumentação , Eletrodos , Medições Luminescentes/instrumentação , Antígeno Prostático Específico/sangue , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise Espaço-Temporal
6.
Anal Chem ; 88(5): 2884-90, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26833237

RESUMO

In this work, we developed a visual electrochemiluminescence (ECL) sensing platform based on a dual-bipolar electrode (D-BPE) array chip. The chip was composed of two arrays of BPEs and three separated arrays of reservoirs filled with buffer, Ru(bpy)3(2+)-TPrA and luminol solutions, respectively. Both BPEs served as ECL reporting platforms. By applying 6.0 V voltage, an array of orange electrochemiluminescence (ECL) signals belonging to Ru(bpy)3(2+) turned on. After adding DNAzyme and H2O2 in Ru(bpy)3(2+) and luminol reservoirs, the orange Ru(bpy)3(2+) signals decreased until vanished due to the quenching effect; meanwhile, a new array of blue ECL signals turned on because of the luminol-H2O2 ECL reaction. The designed D-BPE owns superior properties compared with the three-electrode system benefiting from the quantitative relation of bipolar systems, which greatly enhanced the ECL detection sensitivity. Meanwhile, the visual color-switch ECL and the ratiometric detecting principle made the results easier to evaluate and more accurate. Quantitative detection of HL-60 cancer cells from 320 cells/mL to 2.5 × 10(5) cells/mL with two linear ranges was achieved. The detection limit was down to 80 cells/mL. Finally, this D-BPE chip could distinguish the tumor cells from normal cells and provide a prospect for cancer diagnosis in a high-throughput, visual way.


Assuntos
Técnicas Biossensoriais , Eletroquímica , Eletrodos , Humanos , Luminescência
7.
Biosens Bioelectron ; 77: 76-82, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26397417

RESUMO

In this work, a dual-signaling electrochemiluminescence (ECL) ratiometric sensing approach for the detection of HL-60 cancer cells was reported for the first time. G-C3N4 nanosheets and Ag-PAMAM-luminol nanocomposits (Ag-PAMAM-luminol NCs) were prepared and served as reductive-oxidative and oxidative-reductive ECL emitters respectively. DNA probe functionalized Ag-PAMAM-luminol NCs would hybridize with aptamers modified onto magnetic beads. In the presence of HL-60 cells, the aptamer would conjugate with the target cell and release Ag-PAMAM-luminol NCs. After magnetic separation, released Ag-PAMAM-luminol NCs would hybridize with capture DNA on g-C3N4 nanosheets. ECL from g-C3N4 nanosheets coated on ITO electrode at -1.25 V (vs SCE) could be quenched by Ag-PAMAM-luminol NCs due to the resonance energy transfer (RET) from g-C3N4 nanosheets to Ag NPs. Meanwhile, Ag-PAMAM-luminol brought the ECL signal of luminol at +0.45 V (vs SCE). Thus, the concentration of HL-60 cancer cells could be quantified by both the quenching of ECL from g-C3N4 nanosheets and the enhancement of ECL from luminol. By measuring the ratio of ECL intensities at two excitation potentials, this approach could achieve sensitive and reliable detection for cancer cells in a wide range from 200 cells/mL to 9000 cells/mL with the detection limit of 150 cells (S/N=3).


Assuntos
Contagem de Células/instrumentação , Condutometria/instrumentação , Medições Luminescentes/instrumentação , Luminol/química , Neoplasias Experimentais/patologia , Nitrilas/química , Dendrímeros/química , Desenho de Equipamento , Análise de Falha de Equipamento , Células HL-60 , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Prata/química
8.
Chem Commun (Camb) ; 50(83): 12575-7, 2014 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-25199068

RESUMO

A novel visual electrochemiluminescence (ECL) analysis strategy for detection of telomerase activity is reported on a microarray chip, with G-quadruplex deoxyribozyme (DNAzyme) and luminol modified Au nanoparticles (NPs) as double-catalytic amplification labels.


Assuntos
Técnicas Biossensoriais/métodos , DNA Catalítico/química , Quadruplex G , Ouro/química , Medições Luminescentes/métodos , Luminol/química , Nanopartículas Metálicas/química , Telomerase/metabolismo , Linhagem Celular Tumoral , DNA Catalítico/metabolismo , Humanos , Dispositivos Lab-On-A-Chip , Telomerase/análise
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