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oe1(光电查) - 科学论文

52 条数据
?? 中文(中国)
  • Tuning the electrochemiluminescent properties of iridium complexes of N-heterocyclic carbene ligands

    摘要: A series of five heteroleptic Ir(III) complexes of the general form Ir(dfppy)2(C^C) have been prepared (where dfppy represents 2-(2,4-difluorophenyl)pyridine and C^C represents a bidentate cyclometalated phenyl substituted imidazolylidene ligand). The cyclometalated phenyl ring of the imidazolylidene ligand was either unsubstituted or substituted with electron donating (OMe and Me) or electron withdrawing (Cl and F) groups in the 2 and 4 positions. The synthesised Ir(III) complexes have been characterised by elemental analysis, NMR spectroscopy, cyclic voltammetry and electronic absorption and emission spectroscopy. The molecular structures for four Ir(III) complexes were determined by single crystal X-ray diffraction. Each of the Ir(III) complexes exhibited intense photoluminescence in acetonitrile solution at room temperature with quantum yields (ΦPL) ranging from 58% to 86%. Cyclic voltammetry experiments revealed one oxidation process (formally ascribed to the metal centre), and two ligand-based reductions for each complex. Complexes 1–5 gave moderate to intense annihilation and co-reactant electrochemiluminescence (ECL). Consideration of the electrochemical, spectroscopic and theoretical investigations provide insights into the electrochemiluminescence behaviour.

    关键词: iridium complexes,electrochemiluminescence,cyclic voltammetry,photoluminescence,N-heterocyclic carbene ligands

    更新于2025-09-19 17:15:36

  • An ultrasensitive aptasensor based on self-enhanced Au nanoclusters as highly efficient electrochemiluminescence indicator and multi-site landing DNA walker as signal amplification

    摘要: Gold nanoclusters (Au NCs) have been shown to be prospective nanoscale electrochemiluminescence (ECL) materials that are being extensively explored in bioanalysis. However, the low ECL efficiency of Au NCs has been a bottleneck barrier for their better bioapplications. To overcome this disadvantage, a low oxidation potential co-reactant N,N-diisopropylethylenediamine (DPEA) was first used to prepare self-enhanced Au NCs (Au-DPEA NCs) for drastically enhancing the ECL efficiency of Au NCs in this study. In addition, an efficient multi-site landing DNA walker with multidirectional motion track and rapid payloads release compared to directional DNA walker was constructed for converting target mucin 1 (MUC1) to intermediate DNA and achieving significant signal amplification. On the basis of the Au-DPEA NCs as efficient ECL signal labels and multi-site landing DNA walker as signal amplification strategy, an ECL aptasensor was established for the ultrasensitive detection of MUC1 in the range from 1 fg mL-1 to 1 ng mL-1 with a limit of detection down to 0.54 fg mL-1. The results demonstrated that the present study opened a new research direction for the development of high-efficiency Au NCs indicator as well as ultrasensitive ECL sensing platform for applications in clinical and bioanalysis.

    关键词: Electrochemiluminescence,N-diisopropylethylenediamine,self-enhanced Au nanoclusters,N,multi-site landing DNA walker

    更新于2025-09-19 17:15:36

  • Perylenetetracarboxylic Dianhydride and Aniline Assembled Supramolecular Nanomaterial with Multi-color Electrochemiluminescence for Highly Sensitive Label-free Immunoassay

    摘要: Most electrochemiluminescence (ECL) studies were focused on the single emission of luminophore, which was severely limited the development of 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 emission peaked at 486, 692 and 760 nm with K2S2O8 as coreactant. And the multi-emissions were assigned to excitated 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. And this high efficient ECL nanomaterial was further used as ECL platform to construct label-free immunosensor for tumor markers carcinoembryonic antigen (CEA) detection. The total ECL intensity of immunosensor exhibited a sensitive decrease due to the simultaneously decreased ECL of multi-emissions. And this immunosensor exhibited wide linear range from 1 pg mL-1 to 10 μg mL-1 with low detection limit of 0.23 pg mL-1. Multi-color ECL from the same luminophore PTCDA in this work also provided a new perspective for multi-color ECL biomaterial’s design.

    关键词: supramolecular nanomaterial,multi-color ECL,electrochemiluminescence,aniline,PTCDA,CEA detection,label-free immunosensor

    更新于2025-09-19 17:13:59

  • Principles, mechanisms, and application of carbon quantum dots in sensors: a review

    摘要: The Carbon quantum dots (CQDs) as an emerging class of quantum dots (QDs) with advantages such as good photoluminescence (PL) properties, easy synthesis routes, economical synthesis, cheap starting materials, water-solubility, low level of toxicity, chemical stability, and easy functionalization have received great attention during recent years. The CQDs have been used in versatile sensor applications. The CQDs sensors could be ultimately sensitive, and the limit of detection (LOD) for these sensors can reach the nanomolar, picomolar or even femtomolar ranges. The CQDs-based sensors and biosensors work with different mechanisms including fluorescence quenching, static quenching, dynamic quenching, energy transfer, inner filter effect (IFE), photo-induced electron transfer (PET), and fluorescence resonance energy transfer (FRET). The CQDs-based sensors and biosensors have been applied for detection of different species such as metal ions, acids, proteins, biothiols, polypeptides, DNA and miRNA, water pollutants, hematin, drugs, vitamins, and other chemicals. It seems that the CQDs-based sensors and biosensors are promising candidates for high performance and yet accurate sensors in different areas. In this review, the CQDs are introduced, and the synthesis methods and optical properties of the CQDs are discussed. Different types of CQDs-based sensors and biosensors and their working mechanisms are clarified.

    关键词: Carbon quantum dots,Sensors,Electrochemiluminescence,Photoluminescnece,Chemiluminescence,Fluorescence resonance energy transfer

    更新于2025-09-19 17:13:59

  • A novel electrochemiluminescence sensor based on resonance energy transfer system between nitrogen doped graphene quantum dots and boron nitride quantum dots for sensitive detection of folic acid

    摘要: Electrochemiluminescence resonance energy transfer (ECL-RET) between quantum dots (QDs) was firstly proposed. In this work, boron nitride quantum dots (BNQDs) as the donor and nitrogen doped graphene quantum dots (NGQDs) as the acceptor were confirmed by the absorption spectrum, the emission spectrum and fluorescence spectrum. Based on the reaction between FA and the SO4?? in the ECL system of NGQDs/BNQDs/K2S2O8, the ECL sensing platform for FA was successfully constructed. Surprisingly, a stable and strong ECL signal was obtained based on the RET, which was used for signal-off detection of FA in the presence of coreactant K2S2O8. Notably, about 10-fold enhancement was observed compared with the absence of BNQDs. The proposed sensor showed wide linear ranges of 1.0 × 10?11 M to 1.0 × 10?4 M and a low detection limit of 5.13 × 10?12 M. Simultaneously, the sensor was successfully applied to detection of FA in human serum samples with excellent recoveries. Therefore, the NGQDs/BNQDs system provided a new perspective for development of novel ECL-RET sensors.

    关键词: Folic acid,Nitrogen doped graphene quantum dots,Resonance energy transfer,Boron nitride quantum dots,Electrochemiluminescence

    更新于2025-09-16 10:30:52

  • Wavelength-dependent surface plasmon coupling electrochemiluminescence biosensor based on sulfur doped carbon nitride quantum dots for K-RAS gene detection

    摘要: Although graphite phase carbon nitride quantum dots (GCN QDs) showed some advantages in the electrochemiluminescence (ECL) analytical research, the low ECL efficiency limited the potential sensing application. Herein, we synthesized sulfur doped graphite phase carbon nitride quantum dots (S-GCN QDs) to fabricate a sandwich sensor based on amplified surface plasmon coupling ECL (SPC-ECL) mode. Sulfur doping can change the surface states of QDs effectively and produced new element vacancy. As a result, the ECL efficiency of S-GCN QDs was 2.5 times over GCN QDs. Furthermore, compared with the big gap between the ECL peak of GCN QDs (620 nm) and the absorption peak of Au NPs, the doped sulfur elements in S-GCN QDs generated new ECL emission peaks at 555 nm, which was closed to the absorption peak of Au NPs at 530 nm. Due to the wavelength-dependent surface plasmon coupling effect, the ECL peak of S-GCN QDs at 555 nm had greater amplitude of enhancement in the sensing system. The proposed biosensor can quantify the K-RAS gene from 50 fM to 1 nM with a limit of detection (LOD) of 16 fM. We were the first to provide insight into the role of wavelength-dependent surface plasmon coupling in enhancing the sensitivity of ECL biosensor.

    关键词: wavelength-dependent surface plasmon coupling effect,sulfur doped GCN QDs,K-RAS gene,Electrochemiluminescence

    更新于2025-09-16 10:30:52

  • Electrochemiluminescence resonance energy transfer system between non-toxic SnS2 quantum dots and ultrathin Ag@Au nanosheets for chloramphenicol detection

    摘要: Herein, an efficient electrochemiluminescence energy resonance transfer (ECL-RET) system was first applied in an immunosensor for the detection of chloramphenicol (CAP). SnS2 quantum dots (SnS2 QDs) has an extremely narrow electrochemical emission spectrum, which was used as donor. Compared with conventional quantum dots, toxic-element-free SnS2 QDs exhibit superior environmental friendliness and biocompatibility. Ultrathin Ag@Au nanosheets (Ag@Au NSs) was selected as acceptor due to its excellent structure and controllable UV-vis absorption range. Furthermore, ZnO nanoflowers (ZnO NFs) was employed to modify the electrode surface to provide stable luminescent environment and support more SnS2 QDs. Taking these advantages, the absorption spectra of Ag@Au NSs and the ECL emission spectra of SnS2 QDs are highly matched which ensures the occurrence of ECL-RET. When the CAP analyte were absent, Ag@Au NSs was immobilized on the electrode, and its ultrathin thickness effectively shortens the path of ECL-RET to produce the weak ECL intensity. Inversely, CAP analyte would compete with coating antigen for the certain amount of antibody to remove excess Ag@Au NSs and cause relatively high ECL intensity. As a result, the proposed immunosensor performed satisfactory sensitivity with a wide linear range from 0.005 to 1000 ng mL?1 and a low detection limit (1.7 pg mL?1).

    关键词: Chloramphenicol,Electrochemiluminescence energy resonance transfer,Ag@Au nanosheets,SnS2 quantum dots,Immunosensor

    更新于2025-09-12 10:27:22

  • Electrochemical synthesis of phosphorus and sulfur co-doped graphene quantum dots as efficient electrochemiluminescent immunomarkers for monitoring okadaic acid

    摘要: In this study, water-dispersed, uniform-sized phosphorus and sulfur co-doped graphene quantum dots (P, S-GQDs) were prepared by the one-step electrolysis of a graphite rod in an alkaline solution containing sodium phytate and sodium sulfide. Compared with GQDs and mono-doped GQDs (P-GQDs and S-GQDs), the P, S-GQDs dramatically improved the electrochemiluminescence (ECL) performance. Therefore, they were used as bright ECL signaling markers through conjugation with a monoclonal antibody against okadaic acid (anti-OA-MAb). Moreover, as an effective matrix for OA immobilization, the carboxylated multiwall carbon nanotubes-poly(diallyldimethylammonium) chloride-Au nanocluster (CMCNT-PDDA-AuNCs) composite promoted electron transfer and enlarged the surface area. Owing to the multiple amplifications, a competitive indirect ECL immunosensor for highly sensitive quantitation of OA has been developed. Under the optimized conditions, the 50% inhibitory concentration (IC50) of the immunosensor was 0.25 ng mL-1, and its linear range was 0.01–20 ng mL-1 with a low detection limit of 0.005 ng mL-1. Finally, the proposed ECL sensor was successfully utilized to detect OA contents in mussel samples. Therefore, this study provides new insights into the designation of ECL luminophores and expands application of co-doped GQDs in fabrication of ECL immunosensors for shellfish toxin determination.

    关键词: immunosensor,electrolysis,okadaic acid,electrochemiluminescence,phosphorus and sulfur co-doped graphene quantum dots

    更新于2025-09-12 10:27:22

  • Impact of aminated carbon quantum dots as a novel co-reactant for Ru(bpy)32+: resolving specific electrochemiluminescence for butein detection

    摘要: Development of novel nanomaterial-based co-reactant is highly desired for enhancing ECL intensity and widespread analytical applications. Herein, we report the distinct role of amine-functionalized carbon quantum dots (f-CQDs) as a co-reactant, for the first time, augmenting the ECL property of Ru(bpy)3 2+ and demonstrating for biopharmaceutical (butein) detection. Unlike conventional co-reactants like tripropylamine (TPrA), 2-(dibutylamino)ethanol (DBAE), and pristine CQDs, the f-CQDs as a co-reactant yield superior ECL of Ru(bpy)3 2+. More importantly, the ECL intensity is independent of types of noble metals, metal oxide surfaces, and dissolved oxygen. Notably, the ECL intensity of Ru(bpy)3 2+–f-CQDs is linearly quenched with an increased concentration of butein, whereas no changes were observed with conventional co-reactants. ECL functionality of Ru(bpy)3 2+–f-CQDs has no interference with other similar phytochemicals and antioxidants. Enhanced selectivity is observed due to the formation of polyaminoquinone-like structures, which is confirmed by in situ spectroelectrochemical (UV–vis) and FT-IR studies. The present result envisaged that f-CQDs could be an alternative co-reactant for TPrA/DBAE, raising the ECL of Ru(bpy)3 2+ suitable for analytical studies.

    关键词: Polyphenol,Functionalized carbon quantum dots (f-CQDs),Co-reactant,Electrochemiluminescence,Butein

    更新于2025-09-12 10:27:22

  • Electrochemiluminescence solid-state imprinted sensor based on graphene/CdTe@ZnS quantum dots as luminescent probes for low-cost ultrasensing of diethylstilbestrol

    摘要: A novel molecularly imprinted electrochemiluminescence (MIP-ECL) sensor was fabricated for diethylstilbestrol (DES), which exploited the strategy of specific identification by molecularly imprinted polymers (MIPs) instead of expensive biomolecules. Core-shell quantum-dots (QDs) of CdTe@ZnS were utilized to enhance ECL emission. The sensor was assembled as a solid-state electrode by immobilizing CdTe@ZnS/reduced-graphene oxide (r-GO) composite on a glassy carbon electrode (GCE) surface, and then being covered with MIPs film with specific cavities. The fabricated sensor (denoted as MIP/CdTe@ZnS/r-GO/GCE) was based on the obstruction of ECL signals by DES molecules enriched on MIP film. The ECL intensity of the QDs-K2S2O8 system was reduced when the DES molecules were selectively rebound onto the MIP film by molecularly imprinted solid phase extraction (MISPE). Accordingly, the logarithm of the quenched ECL intensity versus the logarithm of the DES concentration was in a good linear relationship over a wide range from 1.8×10?3 to 25.0 nmol/L with the limit of detection (LOD) of 0.25 pmol/L (S/N = 3). The sensor also exhibits excellent selectivity with fast response and good accuracy. Lake water and milk samples were assayed by this sensor, and the recoveries ranging from 92.2% to 108.3% were obtained.

    关键词: Solid-state electrode,Molecularly imprinted film,Diethylstilbestrol,CdTe@ZnS quantum-dots,Electrochemiluminescence sensor,Solid phase extraction

    更新于2025-09-12 10:27:22