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2.
J Colloid Interface Sci ; 607(Pt 1): 857-868, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34534769

RESUMO

In this study, a new hollow nanotube material, 30% Co-CHNTs was prepared by the impregnation-chemical reduction-calcination method. This material can be used as a peroxymonosulfate (PMS) activator to catalyse the degradation of sulfamethoxazole (SMX). The best reaction conditions that correspond to the degradation rate of SMX, up to 97.5%, are as follows: the concentration of SMX is 10 mg L-1, the amount of catalyst is 0.20 g L-1, the dosage is 1.625 mM, and the solution pH is 6.00. X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectrometry (ICP-OES) show that the calcined composites mainly stimulate an increase in the content of bivalent cobalt in PMS and reduce the leaching of cobalt ions after the reaction. Additionally, the 30% Co-CHNTs + PMS reaction system exhibits a reasonable SMX degradation rate in a natural organic matter solution and excellent stability after three repeated experiments. Furthermore, the possible degradation mechanism in the 30% Co-CHNTs + PMS reaction system was analysed through electron paramagnetic resonance (EPR) and free-radical capture experiments, and it was observed that the non-radical degradation of 1O2 plays a leading role in SMX degradation. Finally, according to the nine degradation intermediates detected by liquid chromatography-mass spectrometry (LC-MS), four possible SMX degradation routes were proposed. This study proved that a 30% Co-CHNTs heterogeneous catalyst is easily prepared, inexpensive, and environmentally friendly and has potential application in antibiotic wastewater treatment.

3.
Talanta ; 235: 122814, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517670

RESUMO

Simple and sensitive detection of telomerase activity is of vital importance for both early diagnosis and therapy of malignant tumors. Inspired by DNA-biobarcode amplification reported by Chad A. Mirkin, we developed a facile DNA-biobarcode-like SERS-based copper-mediated signal amplification strategy for sensitive detection of telomerase activity. In this strategy, a duplex DNA constructed by hybridization of a copper oxide nanoparticle (CuO NP)-labeled reporting sequence (RS) with the telomerase primer sequence (TS) is ingeniously designed, and anchored on the magnetic bead (MB) to build the CuO NPs-encoded magnetic bead (MB-CuO NPs) detection probe. Upon selective sensing of telomerase, telomerase elongation reaction and structure change of TS products make the CuO NP-RS displace and separate from MB. The separated CuO NPs are dissolved into a mass of Cu2+, which prompt monodisperse dopamine-functionalized AgNPs (D-AgNPs) signal probe into aggregation, resulting in color changes and significantly enhancing of SERS signal. The SERS signal increases with the increase of Cu2+, which is directly proportional to the telomerase. Benefiting from the transformation of CuO NP to Cu2+ with a high amplification effect, this strategy could realize the telomerase activity measurement down to 3 HeLa cells and a dynamic range of 10-10000 cells. It shows a significant improvement of sensitivity without need for other enzymes and elaborate design, which escapes from the complicated manipulations and design in polymerase chain reaction (PCR) and DNA amplification techniques. Moreover, with this strategy, telomerase activities of different cell lines and telomerase inhibitors screening were successfully performed. Significantly, it can also be utilized for visual detection of telomerase, which validates the potential on-site application and its application as point-of-care testing (POCT) for efficient monitoring. Given the high-performance for telomerase analysis, the strategy has a promising application in biological detection and clinical diagnosis, as well as point-of-care tests.


Assuntos
Técnicas Biossensoriais , Telomerase , Cobre , DNA , Células HeLa , Humanos , Técnicas de Amplificação de Ácido Nucleico , Telomerase/genética , Telomerase/metabolismo
4.
Ecotoxicol Environ Saf ; 225: 112745, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481349

RESUMO

In the present work, hematite-boron-carbonitride (Fe2O3-BCN) nanosheets were synthesized by a simple hydrothermal reaction and the following high temperature treatment. The morphology, structure and chemical composition of the as-prepared material were carefully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The Fe2O3-BCN nanosheets were used to modified on the surface of the glassy carbon electrode to fabricate an electrochemical sensor for lead ions (Pb(II)) via differential pulse anodic stripping voltammetry (DPASV). At the same time, the influence of the modification concentration, solution acidity, deposition potential and deposition time on response peak current of Pb(II) at the Fe2O3-BCN-based electrochemical sensor was well investigated. Under the optimized conditions, the electrochemical signal and concentration of Pb(II) show two-stage linear relationship in the range of 0.5 - 40 µg/L and 40 -140 µg/L, with a limit of detection (LOD) of 0.129 µg/L. The Fe2O3-BCN-based electrochemical sensor shows excellent selectivity and anti-interference ability in the anti-interference experiments and actual sample analysis experiments, revealing its broad application in environmental monitoring of Pb(II).


Assuntos
Nanopartículas , Água , Compostos Férricos , Íons , Chumbo
5.
Chem Commun (Camb) ; 57(71): 8885-8888, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34486626

RESUMO

A unique ratiometric MALDI-MS strategy is proposed for the convenient and reliable quantitation of alkaline phosphatase based on the homogeneous enzymatic cleavage of a coded phosphopeptide (CPP)-triggered double-signal output. The dynamic range can be tuned by simply adjusting the primary concentration of CPP. The proposed strategy is also capable of being challenged by real human serum, and thus it may offer a wonderful approach for the convenient identification and quantitation of various enzyme activities in clinical diagnosis.


Assuntos
Fosfatase Alcalina/sangue , Fosfatase Alcalina/antagonistas & inibidores , Fosfatase Alcalina/química , Ácido Edético/química , Inibidores Enzimáticos/química , Humanos , Limite de Detecção , Fosfopeptídeos/análise , Fosfopeptídeos/química , Estudo de Prova de Conceito , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
J Craniofac Surg ; 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267134

RESUMO

ABSTRACT: High-voltage (≥1000 V) electrical injury is always related to high mortality and poor prognosis. The incidence rates of the high-voltage electrical injuries of the neck are lower than those of the other parts of the body. This article reports a case of the reconstruction of severe neck scar contracture after electrical injury. Compared with cases of scar contractures caused by nonelectrical injuries, this case had the following remarkable characteristics: extremely severe difficult airway, contracture scars involving whole layers of tissue, muscle and nerve damage, mandibular retraction, and poor occlusal relationship. The chief complaints of the patient upon admission, including forced position and continuous salivation, were greatly relieved through several operations by using different kinds of flaps and offering support to the flap from the palmar tendon and relocated mandible. However, the problem of salivation was incompletely solved. This problem might be caused by damage to related nerves and masticatory muscle function caused by high-voltage electrical injury. The patient was satisfied with the recovery of his appearance and movement function.

7.
Analyst ; 146(11): 3679-3685, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-33955434

RESUMO

In the electrochemiluminescence (ECL) field, most reported luminophores were focused on high-triggering potential and short wavelength, which was adverse for the ECL theory study and application at low potentials. Perylene diimide derivatives could emit near-infrared (NIR) ECL at low-triggering potential; however, they are always highly aggregated into a microrod structure and stacked together, which largely limited their application in biological fields such as bio-sensing and bio-imaging. To overcome these obstacles, we designed a novel perylene diimide molecule, namely N,N'-dicaproate sodium-3,4,9,10-perylenedicarboximide (PDI-COONa). This molecule self-assembled into a two-dimensional network nanostructure, which largely decreased the aggregation degree of PDI molecules and provided solid bases for designing lowly-aggregated PDI molecules. Also, the formed nanoluminophore produced strong emission at -0.26 V with an NIR wavelength 700 nm, which should be due to the excited J-type PDI-COO- dimers. Moreover, this network nanoluminophore well-dispersed on graphene oxide (GO) as an ECL nanomaterial to label secondary antibodies and fabricate a sandwiched immunosensor for alpha-fetoprotein (AFP) detection between 0 and -0.6 V. This immunosensor showed a wider linear response for AFP ranging from 0.1 fg mL-1 to 1 µg mL-1 with a low detection limit 0.0353 fg mL-1 compared with other immunosensors based on PDI microrod-modified GO ECL materials. The fabricated immunosensor also showed good feasibility in human serum samples.


Assuntos
Técnicas Biossensoriais , Perileno , Técnicas Eletroquímicas , Humanos , Imunoensaio , Limite de Detecção , Medições Luminescentes
8.
Biosens Bioelectron ; 181: 113149, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33713951

RESUMO

Chlorothalonil (CHL), imidacloprid (IMI) and oxyfluorfen (OXY) are commonly used in combination to increase crop yield. However, these three pesticides are toxic to aquatic organisms and do not easily degrade. In this study, a surface-enhanced Raman scattering-based lateral flow assay (SERS-LFA) test strip was prepared by combining antibodies with SERS nanotags, and then competitive immune binding was used to detect the three pesticides simultaneously. Moreover, the two-way binding effect of ssDNA-streptavidin bound to Ag4-NTP@AuNPs and Ag4-NTP@AuNPs with antibodies was used to further amplify the detection signal. Under the optimal conditions, the SERS-LFA test strips exhibited high sensitivity, a low detection limit, short detection time, high specificity and low cost. Furthermore, the detection range was within the values prescribed by international detection standards. By measuring the intensity of the SERS signal on the test line of the paper strip, accurate quantitative analysis was achieved. The practical application of the proposed system was demonstrated by simultaneous detection of CHL, IMI and OXY in environmental and food samples with satisfactory results.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Praguicidas , Ouro , Análise Espectral Raman
9.
Analyst ; 146(8): 2705-2711, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33751013

RESUMO

A novel ratiometric electrochemical biosensing strategy based on T7 exonuclease (T7 Exo)-assisted homogenous target recycling coupling hairpin assembly triggered dual-signal output was proposed for the accurate and sensitive detection of microRNA-141 (miRNA-141). Concretely, in the presence of target miRNA, abundant signal transduction probes were released via the T7 Exo-assisted homogenous target recycling amplification, which could be captured by the specially designed ferrocene-labeled hairpin probe (Fc-H1) on -electrode interface and triggered the nonenzymatic catalytic hairpin assembly (Fc-H1 + MB-H2) to realize the cascade signal amplification and dual-signal output. Through such a conformational change process, the electrochemical signal of Fc (IFc) and MB (IMB) is proportionally and substantially decreased and increased. Therefore, the signal ratio of IMB/IFc can be employed to accurately reflect the true level of original miRNA. Benefiting from the efficient integration of the T7 Exo-assisted target recycle, nonenzymatic hairpin assembly and dual-signal output mode, the proposed sensor could realize the amplified detection of miRNA-141 effectively with a wide detection range from 1 fM to 100 pM, and a detection limit of 200 aM. Furthermore, it exhibits outstanding sequence specificity to discriminate mismatched RNA, acceptable reproducibility and feasibility for real sample. This strategy effectively integrated the advantages of multiple amplification and ratiometric output modes, which could provide an accurate and efficient method in biosensing and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , MicroRNAs , Técnicas Eletroquímicas , Exodesoxirribonucleases , Limite de Detecção , MicroRNAs/genética , Reprodutibilidade dos Testes
10.
J Craniofac Surg ; 32(6): e551-e554, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33606439

RESUMO

ABSTRACT: Localized scleroderma is a rare soft tissue disorder characterized by a thickening of the skin from excessive collagen deposits. For patients with face involved, soft tissue depression and atrophy could cause serious facial contour deformity and adversely affect the patients' quality of social life. However, localized scleroderma cases with delicate facial aesthetic subunits defects were rarely reported to be surgically reconstructed. In this study, we present 2 patients with nasal subunits and oral subunit deformities caused by localized scleroderma respectively. The first patient with a right-side alar defect and nasal dorsum depression, forehead depression and eyebrow depression were treated through a 2-stage surgical approach, with microvascular preauricular and helical rim flap and dermofat graft transplantation. The lower lip and mandible defects of the second patient were reconstructed with a combination of submental flap and fat grafting. The transplanted dermofat graft, fat graft, the microvascular free flap, and the submental flap survived completely and maintained adequate tissue volume and facial contour during the follow-up time of 2 years. Both patients were satisfied with the overall aesthetic results. This clinical report supports the use of microsurgical flap and tissue grafts on the treatment of localized scleroderma (LS) caused facial aesthetic subunits deformities.


Assuntos
Retalhos de Tecido Biológico , Neoplasias Nasais , Procedimentos Cirúrgicos Reconstrutivos , Rinoplastia , Esclerodermia Localizada , Estética Dentária , Humanos , Neoplasias Nasais/cirurgia
11.
Chem Commun (Camb) ; 56(75): 11074-11077, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32812587

RESUMO

A DNA immobilization-free ECL aptasensor was developed for the detection of 8-hydroxy-2'-deoxygunosine based on the diffusion mediated ECL quenching effect. This ECL aptasensor exhibited a high sensitivity and low detection limit by combining homogeneous DNA reaction with dual signal amplifications: target-induced multi-DNA release and Exo I-assisted target recycling.

12.
Analyst ; 145(15): 5174-5179, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32613972

RESUMO

In this work, a method for quantifying the activity of formamidopyrimidine DNA glucosylase (Fpg) was designed based on phosphate group (P)-modulated multi-enzyme catalysis and fluorescent copper nanoclusters (CuNCs). By eliminating 8-oxoguanine from double-stranded DNA, Fpg generates a nick with P at both 3' and 5' termini. Subsequently, part of the DNA is digested by 5'P-activated lambda exonuclease (λ Exo), and the generated 3'P disables exonuclease I (Exo I), resulting in the generation of single-stranded DNA containing poly(thymine) (poly(T)). Using poly(T) as templates, CuNCs were prepared to emit intense fluorescence as the readout of this method. However, in the absence of Fpg, the originally modified 5'P triggers the digestion of λ Exo. In this case, fluorescence emission is not obtained because CuNCs cannot be formed without DNA templates. Therefore, the catalysis of λ Exo and Exo I can be tuned by 5'P and 3'P, which can be further used to determine the activity of Fpg. The fluorescent Fpg biosensor works in a "signal-on" manner with the feature of "zero" background noise, and thus shows desirable analytical features and good performance. Besides, Fpg in serum samples and cell lysate could be accurately detected with the biosensor, indicating the great value of the proposed system in practical and clinical analysis.


Assuntos
Técnicas Biossensoriais , Cobre , Catálise , DNA , Fosfatos
13.
ACS Appl Mater Interfaces ; 12(24): 26905-26913, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32427457

RESUMO

Quantitative analysis of receptor protein expression is essential to give new insights into tumor-related research. Benefitting from their high sensitivity and low background, photoelectrochemical (PEC) platforms are considered as powerful tools for evaluating the expression of receptor proteins. Herein, to reduce the cytotoxicity and facilitate the subsequent assembly, l-cysteine-modified Ag-ZnIn2S4 quantum dots (l-Cys AZIS QDs) are prepared and PEC responses under the irradiation of long wavelength light are obtained. To further improve the PEC behavior, iron phthalocyanine (FePc) is employed to form a Z-scheme structure with l-Cys AZIS QDs. The Z-scheme structure based on l-Cys AZIS QDs/FePc hybrid materials exhibits high photo-to-electric conversion efficiency and can be excited with near-infrared range light. Because hyaluronic acid linked to photoactive materials can recognize CD44 expressed on the membrane of cancer cells, cancer cells are immobilized onto l-Cys AZIS QDs/FePc hybrid materials, inducing a decrease of the photocurrent intensity. Consequently, a PEC cytosensor is constructed to quantify cancer cells expressing CD44. The PEC analytical platform is able to determine A549 cells in the range of 2 × 102 to 4.5 × 106 cells/mL, and a detection limit of 15 cells/mL is realized in the case of S/N = 3. In addition, the expression of CD44 in A549 and other five cancer cells is measured with this PEC method. Depending on our data, the expression of CD44 in different cancer cells is distinct, indicating great potential of this method in receptor protein-related studies.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Fotoquímica/métodos , Células A549 , Humanos , Receptores de Hialuronatos/metabolismo , Pontos Quânticos
14.
Analyst ; 145(10): 3605-3611, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32266898

RESUMO

A sensitive and enzyme-free electrochemical aptasensor was constructed for the sensing of 8-hydroxy-2'-deoxyguanosine (8-OH-dG). In the process of constructing the aptasensor, triple signal amplification strategies were introduced to enhance the sensitivity. First, every aptamer/pDNA complex immobilized on magnetic beads could release three kinds of pDNAs when 8-OH-dG was introduced, which caused three-fold magnification of the target. Second, the released three kinds of pDNAs initiated catalyzed hairpin assembly between two hairpin DNAs (HP1 and HP2) on a gold electrode. Meanwhile, the three kinds of pDNAs were released again by a strand displacement reaction to obtain the next catalyzed hairpin assembly. Third, the emerging toehold of HP2 further induced a hybridization chain reaction (HCR) between two hairpin DNAs (HP3 and HP4), forming a long double-stranded DNA concatemer on the surface of the electrode. Finally, [Ru(NH3)6]3+, an electroactive cation, was adsorbed onto the long dsDNA concatemer by electrostatic interactions and consequently, an electrochemical signal was generated. Under this triple signal amplification, a low detection limit down to 24.34 fM has been obtained for 8-OH-dG determination, which is superior to those of most previously reported methods.


Assuntos
8-Hidroxi-2'-Desoxiguanosina/análise , Biocatálise , Técnicas Biossensoriais/métodos , DNA/química , DNA/genética , Sequências Repetidas Invertidas , 8-Hidroxi-2'-Desoxiguanosina/química , 8-Hidroxi-2'-Desoxiguanosina/urina , Aptâmeros de Nucleotídeos/metabolismo , Eletroquímica , Humanos , Hibridização de Ácido Nucleico
15.
Chem Commun (Camb) ; 56(31): 4288-4291, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32182314

RESUMO

The tough challenges for the sensitive and accurate detection of circulating miRNAs (cmiRNAs) in the peripheral blood are low abundance, and high interference from environmental or background factors or other molecules. Here, we developed a double-signal mode based on metal-organic framework coupled cascaded nucleic acid circuits for the accurate and sensitive detection of serum circulating miRNAs.


Assuntos
Técnicas Biossensoriais/métodos , MicroRNA Circulante/sangue , Sondas de DNA/química , DNA/química , Estruturas Metalorgânicas/química , MicroRNA Circulante/genética , DNA/genética , Sondas de DNA/genética , Corantes Fluorescentes/química , Glucose Oxidase/química , Humanos , Peróxido de Hidrogênio/química , Limite de Detecção , MicroRNAs/sangue , MicroRNAs/genética , Hibridização de Ácido Nucleico , Oxirredução , Fenazinas/química , Fenilenodiaminas/química , Espectrometria de Fluorescência/métodos
16.
J Hazard Mater ; 391: 122207, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32036313

RESUMO

Manganese oxides show strong affinity towards uranium, and have a promising application in uranium immobilization in environmental protection. We successfully synthesized a series of Mn oxide materials of different structures and investigated their U(VI) immobilization performances. The results showed that all Mn oxides share similar sorption capacities per unit surface area, implying similar physical chemistry during immobilization. Among these Mn oxides, α-MnO2 shows the most outstanding performance for uranium uptake (280 mg/g). More detailed studies on interfacial properties of U(VI) on α-MnO2 were performed to elucidate the binding mechanism. The uptake was largely influenced by acidity, but less impacted by ionic strength, indicative of an inner-sphere binding mode. The selectivity for uranium is much higher than other selected metal ions, i.e. Co2+, Ni2+, Eu3+, etc. ATR-FTIR, and EXAFS results showed that in both mild acidic and neutral conditions, U(VI) formed bidentate binuclear structure on α-MnO2, as evidenced by υas(O = U=O) at 912 cm-1 and the number of Mn in U coordination shell. UO2(OH)2 precipitate was found at the molecular level in neutral condition (pH 7-8). The results reveal the physical chemistry in uranium immobilization process on manganese oxide surfaces and helps to better understand the uranium environmental migration. Furthermore, it provides an alternative approach for radioactive water purification.

17.
J Mater Chem B ; 8(16): 3676-3682, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32096516

RESUMO

Most electrochemiluminescence (ECL) studies focus on the single emission of luminophores, which severely limits the development of the multi-color ECL fundamental theory and applications. Herein, we prepared a multi-color ECL supramolecular nanomaterial self-assembled by 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and aniline (An) through hydrogen bonding. This PTCDA-An supramolecular nanomaterial simultaneously produced multi-color emissions peaking at 486, 692 and 760 nm with K2S2O8 as a coreactant. These multi-color emissions were assigned to the excited PTCDA monomer (486 nm), H-dimer (692 nm) and J-dimer (760 nm). The simultaneously increased dual-color ECL intensity significantly enhanced the total ECL intensity of PTCDA-An. Furthermore, this highly efficient ECL nanomaterial was used as an ECL platform to construct a label-free immunosensor for tumor marker carcinoembryonic antigen (CEA) detection. The total ECL intensity of the immunosensor sensitively decreased due to the simultaneously decreased ECL of multiple emissions. Also, this immunosensor exhibited a wide linear range from 1 pg mL-1 to 10 µg mL-1 with a low detection limit of 0.23 pg mL-1. The multi-color ECL from the same luminophore PTCDA in this work also provides a new perspective for multi-color ECL biomaterial design.


Assuntos
Anidridos/química , Compostos de Anilina/química , Biomarcadores Tumorais/análise , Antígeno Carcinoembrionário/análise , Cor , Nanoestruturas/química , Perileno/análogos & derivados , Técnicas Biossensoriais , Técnicas Eletroquímicas , Humanos , Imunoensaio , Medições Luminescentes , Substâncias Macromoleculares/química , Estrutura Molecular , Tamanho da Partícula , Perileno/química , Propriedades de Superfície
18.
Angew Chem Int Ed Engl ; 59(9): 3455-3459, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31808988

RESUMO

The synthesis of hierarchical nanosized zeolite materials without growth modifiers and mesoporogens remains a substantial challenge. Herein, we report a general synthetic approach to produce hierarchical nanosized single-crystal aluminophosphate molecular sieves by preparing highly homogeneous and concentrated precursors and heating at elevated temperatures. Accordingly, aluminophosphate zeotypes of LTA (8-rings), AEL (10-rings), AFI (12-rings), and -CLO (20-rings) topologies, ranging from small to extra-large pores, were synthesized. These materials show exceptional properties, including small crystallites (30-150 nm), good monodispersity, abundant mesopores, and excellent thermal stability. A time-dependent study revealed a non-classical crystallization pathway by particle attachment. This work opens a new avenue for the development of hierarchical nanosized zeolite materials and understanding their crystallization mechanism.

19.
Biosens Bioelectron ; 150: 111880, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31748194

RESUMO

Novel optical labels for biosensing in near-infrared (NIR) region (especially between 800 and 900 nm) are arousing much attention for higher penetrating capability, less scattering and lowered autofluorescent background. Herein, a water-soluble electrochemiluminophore with effective electrochemiluminescence (ECL) around 815 nm is developed via doping dual-stabilizers-capped CdTe nanocrystals (NCs) with Co2+ species in a growth-doping way. The Co2+-doped CdTe NCs not only can preserve the highly-passivated surface states of dual-stabilizers-capped CdTe NCs, but also exhibit efficient red-shifted photoluminescence (PL) and ECL into the promising optical NIR window of 800-900 nm. A spectrum-based ultrasensitive NIR ECL immunosensor is consequently fabricated with the Co2+-doped CdTe NCs as tags for the first time, which can selectively and sensitively determine human carcinoembryonic antigen with a wide linearity range from 1 fg/mL to 10 pg/mL and a low limit of detection at 0.2 fg/mL (S/N = 3). This work opens a way to screen novel NIR electrochemiluminophore as well as to modulate the ECL performance of NCs via surface doping and engineering.


Assuntos
Compostos de Cádmio/química , Antígeno Carcinoembrionário/análise , Cobalto/química , Nanopartículas/química , Telúrio/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Humanos , Raios Infravermelhos , Limite de Detecção , Medições Luminescentes/métodos
20.
Nanoscale ; 11(43): 20910-20916, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31660563

RESUMO

In the cathodic electrochemiluminescence (ECL) field, most reported luminophores produced ECL emission at high potentials (more than -1.3 V vs. Ag/AgCl), which was adverse for both fundamental studies and practical application. It was important to screen novel ECL luminophores and coreactants for the development of ECL. In this work, N,N'-dimethyl-3,4,9,10-perylenedicarboximide (PDI-CH3) is reported to produce ECL at -0.47 V using K2S2O8 as a coreactant in an aqueous system. In addition, the ECL wavelength was 689 nm, which was interpreted with the emission of excited PDI-CH3 dimers. Finally, this low-triggering-potential ECL system was used to construct sandwiched immunosensors to detect carcinoembryonic antigen (CEA) with the potential range from 0 to -0.8 V. In this immunosensor, PDI-CH3 and gold nanoparticles (AuNPs) reduced by citrate were grafted onto graphite oxide (GO) to label secondary antibodies (Ab2). This immunosensor could sensitively detect CEA with the linear response range between 1 fg mL-1 and 1 µg mL-1 and detection limit 0.29 fg mL-1. In addition, this immunosensor showed good feasibility in various cancer serum samples.


Assuntos
Corantes Fluorescentes/química , Imidas/química , Imunoensaio/métodos , Perileno/análogos & derivados , Anticorpos/imunologia , Antígeno Carcinoembrionário/análise , Antígeno Carcinoembrionário/imunologia , Técnicas Eletroquímicas , Eletrodos , Ouro/química , Grafite/química , Limite de Detecção , Medições Luminescentes , Nanopartículas Metálicas/química , Perileno/química
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