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1.
Electrochemical behavior and electrogenerated chemiluminescence (ECL) of tris(2,2′-bipyridyl)ruthenium(II) (Ru(bpy)32+) immobilized in poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate)-poly(vinyl alcohol) (PEDOT/PSS-PVA) composite films via ion-exchange have been investigated with tripropylamine (TPA) as the co-reactant at a glassy carbon electrode. The immobilized Ru(bpy)32+ performed a surface-controlled electrode reaction. The Ru(bpy)32+ modified electrode showed a fast ECL response to TPA, and was used for the ECL detection of TPA with high sensitivity. The ECL intensity was linearly related to concentrations of TPA over the range from 0.50 μmol L−1 to 0.80 mmol L−1, and the detection limit was 0.10 μmol L−1 (S/N = 3). The as-prepared electrode exhibited good precision and long-term stability for TPA determination.  相似文献   

2.
Different effects of divalent metal ions on electrochemiluminescence (ECL) sensor with Ru(bpy)32+ immobilized in Eastman‐AQ membrane were investigated. Mg2+, Ca2+ and Fe2+ can elevate the ECL of Ru(bpy)32+/proline; while metal ions that underwent redox reactions on the electrode such as Mn2+ and Co2+ presented intensive quenching effects on Ru(bpy)32+ ECL. Also, the quenching effect of Mn2+ on the ECL sensor with Ru(bpy)32+ immobilized in Eastman‐AQ membrane enhanced to about 30‐folds compared with the case that Ru(bpy)32+ was dissolved in phosphate buffer, and the enhanced quenching effects of Mn2+ were studied.  相似文献   

3.
A novel electrogenerated chemiluminescence (ECL) sensor based on Ru(bpy)32+‐doped titania (RuDT) nanoparticles dispersed in a perfluorosulfonated ionomer (Nafion) on a glassy carbon electrode (GCE) was developed in this paper. The electroactive component‐Ru(bpy)32+ was entrapped within the titania nanoparticles by the inverse microemulsion polymerization process that produced spherical sensors in the size region of 38±3 nm. The RuDT nanoparticles were characterized by electrochemical, transmission electron and scanning microscopy technology. The Ru(bpy)32+ encapsulation interior of the titania nanoparticles maintains its ECL efficiency and also reduces Ru(bpy)32+ leaching from the titania matrix when immersed in water due to the electrostatic interaction. This is the first attempt to prepare the RuDT nanoparticles and extend the application of electroactive component‐doped nanoparticles into the field of ECL. Since a large amount of Ru(bpy)32+ was immobilized three‐dimensionally on the electrode, the Ru(bpy)32+ ECL signal could be enhanced greatly, which finally resulted in the increased sensitivity. The ECL analytical performance of this ECL sensor for tripropylamine (TPA) was investigated in detail. This sensor shows a detection limit of 1 nmol/L for TPA. Furthermore, the present ECL sensor displays outstanding long‐term stability.  相似文献   

4.
In this work, a stable electrogenerated chemiluminescence (ECL) detector was developed. The detector was prepared by packing cation-exchanged resin particles in a glass tube, followed by inserting Pt wires (working electrode) in this tube and sealing. The leakage of Ru(bpy)32+ can be compensated by adding a small amount of Ru(bpy)32+ into solution phase. Coupled with high-performance liquid chromatography separation, the detector has been used for determination of itopride hydrochloride in human serum. Under the optimal conditions, the ECL intensity has a linear relationship with the concentration of itopride hydrochloride in the range of 1.0 × 10−8 g mL−1 to 1.0 × 10−6 g mL−1 and the detection limit was 3 × 10−9 g mL−1 (S/N = 3). The as-prepared ECL detector displayed good sensitivity and stability.  相似文献   

5.
《Electroanalysis》2004,16(17):1401-1405
The immobilization of tris(2,2′‐bipyridyl)ruthenium(II), Ru(bpy)32+, at a glassy carbon electrode was achieved by entrapping the Ru(bpy)32+ in a vapor deposited titania sol‐gel membrane. The electrogenerated chemiluminescence (ECL) of the immobilized Ru(bpy)32+ was studied. The Ru(bpy)32+ modified electrode showed a fast ECL response to both oxalate and proline. The ECL intensity was linearly related to concentrations of oxalate and proline over the ranges from 20 to 700 μmol L?1 and 20 to 600 μmol L?1, respectively. The detection limits for oxalate and proline at 3σ were 5.0 μmol L?1 and 4.0 μmol L?1, respectively. This electrode possessed good precision and stability for oxalate and proline determinations. The electrogenerated chemiluminescence mechanism of proline system was discussed. This work provided a new way for the immobilization of Ru(bpy)32+ and the application of titania sol‐gel membrane in electrogenerated chemiluminescence.  相似文献   

6.
A novel electrogenerated chemiluminescence (ECL) sensor based on natural clay and ionic liquid was fabricated. Tris(2,2′‐bipyridine)ruthenium(II) (Ru(bpy)32+) was immobilized on natural clay surface through simple adsorption. An ECL sensor was prepared by mixing Ru(bpy)32+‐incorporated clay, graphite powder and an ionic liquid (1‐butyl‐3‐methylimidazolium hexafluorophosphate) as the binder. The electrochemical behavior and ECL of the immobilized Ru(bpy)32+ was investigated. It was observed that the ECL of immobilized Ru(bpy)32+ was activated by the ionic liquid. The proposed ECL sensor showed high sensitivity to tri‐n‐propylamine (TPrA) and the detection limit was found to be 20 pM. In addition, the ECL sensor displayed good stability for TPrA detection and long‐term storage stability.  相似文献   

7.
Ru(bpy) 3 2+ electrogenerated chemiluminescence (CL) has rapidly gained importance as a sensitive and selective detection method in analytical science. The Ru(bpy) 3 2+ ECL is observed when Ru(bpy) 3 3+ reacts with Ru(bpy) 3 + and yields an excited state Ru(bpy) 3 2+* . ECL emission can also be obtained when a variety of oxidants and reductants react with the reduced or oxidized forms of Ru(bpy) 3 2+ . Either the reductant or the oxidant can be treated as an analyte. The Ru(bpy) 3 2+ ECL is used as a detection method for the determination of oxalate and a variety of amine-containing analytes without derivatization in flowing streams such as flow injection and HPLC. When the ECL format is used as a detector for HPLC, unstable post-column reagent addition can often be eliminated and, the problems of both sample dilution and band broadening can be avoided because the Ru(bpy) 3 3+ species are generatedin situ in the reaction/observation flow cell. Since NADH is sensitively detected with the Ru(bpy) 3 2+ ECL, many clinically important analytes can be detected by coupling them to dehydrogenase enzymes that utilize -nicotinamide adenine cofactors to convert NAD+ to NADH. Ru(bpy) 3 2+ -derivatives are used as CL labels for immunoassay and PCR assay with Ru(bpy) 3 2+ /tripropylamine ECL system. The Ru(bpy) 3 2+ ECL label can be sensitively determined at subpicomolar concentrations, along with an extremely wide dynamic range of greater than six orders of magnitude. Furthermore, it can eliminate disposal and lifetime problems inherent in radio immunoassays. In this paper, basic principles of the Ru(bpy) 3 2+ ECL are discussed. In addition, analytical applications of the Ru(bpy) 3 2+ ECL are illustrated with examples.  相似文献   

8.
A highly sensitive and stable tris(2,2′-bipyridyl)ruthenium(II) (Ru(bpy)32+) electrogenerated chemiluminescence (ECL) sensor was developed based on carbon nanotube (CNT) dispersed in mesoporous composite films of sol-gel titania and perfluorosulfonated ionomer (Nafion). Single-wall (SWCNT) and multi-wall carbon nanotubes (MWCNT) can be easily dispersed in the titania-Nafion composite solution. The hydrophobic CNT in the titania-Nafion composite films coated on a glassy carbon electrode certainly increased the amount of Ru(bpy)32+ immobilized in the ECL sensor by adsorption of Ru(bpy)32+ onto CNT surface, the electrocatalytic activity towards the oxidation of hydrophobic analytes, and the electronic conductivity of the composite films. Therefore, the present ECL sensor based on the CNT-titania-Nafion showed improved ECL sensitivity for tripropylamine (TPA) compared to the ECL sensors based on both titania-Nafion composite films without CNT and pure Nafion films. The present Ru(bpy)32+ ECL sensor based on the MWCNT-titania--Nafion composite gave a linear response (R2 = 0.999) for TPA concentration from 50 nM to 1.0 mM with a remarkable detection limit (S/N = 3) of 10 nM while the ECL sensors based on titania-Nafion composite without MWCNT, pure Nafion films, and MWCNT-Nafion composite gave a detection limit of 0.1 μM, 1 μM, and 50 nM, respectively. The present ECL sensor showed outstanding long-term stability (no signal loss for 4 months).  相似文献   

9.
An ultrasensitive electrogenerated chemiluminescence (ECL) immunoassay was proposed by using magnetic nanobeads (MNBs) as the carrier of ECL labels for ECL emission amplification. Carcinoembryonic antigen (CEA) and MNBs were initially immobilized on a platform in 1 : 1 molar ratio via sandwich immunoreaction. Subsequently, the MNBs were released from the platform and labeled with Ru(bpy)32+ species. After the MNBs with Ru(bpy)32+ were immobilized on an Au electrode, ECL of the Ru(bpy)32+ was measured for CEA determination. A linear relation between the ECL intensity and CEA concentration was obtained in a range of 1×10?14 to 3×10?13 mol/L (2.0 to 60 pg/mL) with a limit of detection of 8.0×10?15 mol/L (1.6 pg/mL).  相似文献   

10.
An effective electrochemiluminescence (ECL) sensor based on Nafion/poly(sodium 4-styrene sulfonate) (PSS) composite film-modified ITO electrode was developed. The Nafion/PSS/Ru composite film was characterized by atomic force microscopy, UV-vis absorbance spectroscopy and electrochemical experiments. The Nafion/PSS composite film could effectively immobilize tris(2,2′-bipyridyl)ruthenium(II) (Ru(bpy)32+) via ion-exchange and electrostatic interaction. The ECL behavior of Ru(bpy)32+ immobilized in Nafion/PSS composite film was investigated using tripropylamine (TPA) as an analyte. The detection limit (S/N = 3) for TPA at the Nafion/PSS/Ru composite-modified electrode was estimated to be 3.0 nM, which is 3 orders of magnitude lower than that obtained at the Nafion/Ru modified electrode. The Nafion/PSS/Ru composite film-modified indium tin oxide (ITO) electrode also exhibited good ECL stability. In addition, this kind of immobilization approach was simple, effective, and timesaving.  相似文献   

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