Sensitive chemically amplified electrochemical detection of ruthenium tris-(2,2′-bipyridine) on tin-doped indium oxide electrode

Zheng, Dong; Wang, Na; Wang, Fu-Quan; Dong, Dong; Li, Yuanguang; Yang, Xiqiang; Guo, Liang-Hong; Cheng, Jing

doi:10.1016/j.aca.2003.12.002

Cited by 41 publications

(20 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We employed catalytic voltammetry for the determination of various biological binding assays [31][32][33]. With this method, a Ru-bipy derivative is attached either covalently or non-covalently to a biological binding pair as a redox label.…”

mentioning

confidence: 99%

Determination of Surface-Immobilized Double-Stranded DNA Using a Metallointercalator and Catalytic Voltammetry

2006

Self Cite

View full text Add to dashboard Cite

Abstract. DNA films immobilized on an indium tin oxide (ITO) electrode surface were detected and determined employing a high-affinity intercalator, Ru(bpy) 2 (dppz) 2þ (bpy ¼ 2,2 0 -bipyridine, dppz ¼ dipyrido[3,2-a:2 0 ,3 0 -c]phenazine), as a redox indicator, and oxalate as a sacrificial electron donor in solution to chemically amplify the voltammetric signal of the indicator. Nucleic acids were immobilized on ITO by layer-by-layer electrostatic adsorption, using avidin as the first layer and nucleic acid as the second layer. In quartz crystal microbalance (QCM) measurements on an avidin-coated gold surface, the amount of adsorption from a 200 mg mL À1 nucleic acid solution was found to be 3.2 ng mm À2 for both double-stranded (ds-) and single-stranded (ss-) calf-thymus DNA as well as polycytidylic acid (Poly-C). After binding with Ru(bpy) 2 (dppz) 2þ (Ru-dppz), voltammetry of the ds-DNA film on ITO was carried out in an indicator-free phosphate buffer. An anodic peak at about 1.15 V was observed, and it was assigned to Ru-dppz oxidation. When measured in an oxalate buffer, however, a catalytic current was observed due to the oxidation of oxalate by electrochemically generated Ru(bpy) 2 (dppz) 3þ , resulting in a 120-fold increase in the signal. Since oxalate itself produces a very low oxidation current on ITO, catalytic voltammetry produces about a 14-fold improvement in the signal-to-blank ratio over the nonamplified determination. As a result, ds-DNA adsorbed from 20 ng mL À1 solution could be detected, which was estimated by QCM to be 160 pg mm À2 on the surface. The catalytic current of ds-DNA was substantially higher than that of ss-DNA and poly-C, indicative of selective binding of the redox indicator to ds-DNA. The results serve as a basis for the catalytic voltammetric detection of DNA hybridization in future work.

show abstract

mentioning

confidence: 99%

Determination of Surface-Immobilized Double-Stranded DNA Using a Metallointercalator and Catalytic Voltammetry

2006

Self Cite

View full text Add to dashboard Cite

show abstract

“…We have previously reported a catalytic voltammetry system aimed for the detection of biological affinity reactions [33]. The system employs ruthenium Tris-(4,4 -bipyridine) (Ru-bipy) as an electrochemical label and oxalate as a sacrificial electron donor to chemically amplify the anodic current of Ru-bipy on tin-doped indium oxide (ITO) electrode.…”

Section: E-mail Addressmentioning

confidence: 99%

Enhanced electrochemical activity of redox-labels in multi-layered protein films on indium tin oxide nanoparticle-based electrode

Yang

Guo

2009

Analytica Chimica Acta

Self Cite

View full text Add to dashboard Cite

a b s t r a c tFacile electrical communication between redox-active labeling molecules and electrode is essential in the electrochemical detection of bio-affinity reactions. In this report, nanometer-sized indium tin oxide (ITO) particles were employed in the fabrication of porous thick film electrodes to enhance the otherwise impeded electrochemical activity of redox labels in multi-layered protein films, and to enable quantitative detection of avidin/biotin binding interaction. To carry out the affinity reaction, avidin immobilized on an ITO electrode was reacted with mouse IgG labeled with both biotin and ruthenium Tris-(2,2 -bipyridine) (Ru-bipy). The binding reaction between avidin and biotin was detected by the catalytic voltammetry of Ru-bipy in an oxalate-containing electrolyte. On sputtered ITO thin film electrode, although a single layer of Ru-bipy labeled avidin exhibited substantial anodic current, attaching the label to the outer IgG layer of the avidin/biotin-IgG binding pair resulted in almost complete loss of the signal. However, electrochemical current was recovered on ITO film electrodes prepared from nanometer-sized particles. The surface of the nanoparticle structured electrode was found by scanning electron microscopy to be very porous, and had twice as much surface binding capacity for avidin as the sputtered electrode. The results were rationalized by the assumption of different packing density of avidin inner layer on the two surfaces, and consequently different electron transfer distance between the electrode and Ru-bipy on the IgG outer layer. A linear relationship between electrochemical current and IgG concentration was obtained in the range of 40-4000 nmol L −1 on the nanoparticle-based electrode. The approach can be employed in the electrochemical detection of immunoassays using non-enzymatic redox labels.

show abstract

“…To be suitable for chemically amplified electrochemical detections, the electrode must enable a fast electron exchange with the redox analyte, but perform negligible electrochemical reactions with the electron donor (i.e., amplifier) [9]. The 4-nitrophenyl grafted glassy carbon electrode described above detected amplified anodic currents of ferrocenemethanol in the presence of ferrocyanide in an aqueous solution as an amplifier (Fig.…”

Section: Chemical Amplification Of Ferrocenemethamentioning

confidence: 99%

“…Signal amplification factors were obtained in several hundred to thousands facilitating a flow injection in a concentration range between 10 −4 and 10 −7 M. A lower detection limit of chemical amplification was studied with tris(2,2'-bipyridyl)dichlororuthenium(II) hexahydrate as the redox analyte and sodium oxalate as the electron donor on the ITO glass electrodes demonstrating a lower detection limit of approximately 50 nM [9]. However, further improvement is required to achieve real-time electrochemical detection for biological determination.…”

Section: Introductionmentioning

confidence: 99%

“…However, the electrochemical signal from single redox label provides only one or two electrons and the double-layer charging limits the sensitivity of detection. Therefore chemical amplification has studied as a way of enhancing the electrochemical signal and thus improving its sensitivity [1][2][3][4][5][6][7][8][9]. In the chemical amplification, an amplifier-a reagent enabling electron transfer with the oxidized or reduced form of the analytepresents in solution while the reaction is kinetically suppressed or blocked on the electrode surface.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Simple and Ultrasensitive Chemically Amplified Electrochemical Detection of Ferrocenemethanol on 4-Nitrophenyl Grafted Glassy Carbon Electrode

Koh

Lee

Song

et al. 2016

Journal of Electrochemical Science and Technology

View full text Add to dashboard Cite

Chemically amplified electrochemical detection, redox-active probe being amplified its electrochemical anodic current by a sacrificial electron donor presenting in solution, holds great potential for simple and quantitative bioanalytical analysis. Herein, we report the chemically amplified electrochemical analysis that drastically enhanced a detection of ferrocenemethanol (analyte) by ferrocyanide (chemical amplifier) on 4-nitrophenyl grafted glassy carbon electrodes at 60 o C. The glassy carbon electrode grafted with a 4-nitrophenyl group using an electrochemical reduction suppressed the oxidation of ferrocyanide and thus enabled detection of ferrocenemethanol with excellent selectivity. The ferrocenemethanol was detected down to an nM range using a linear sweep voltammetry under kinetically optimized conditions. The detection limit was improved by decreasing the concentration of the ferrocyanide and increasing temperature.

show abstract

Sensitive chemically amplified electrochemical detection of ruthenium tris-(2,2′-bipyridine) on tin-doped indium oxide electrode

Cited by 41 publications

References 35 publications

Determination of Surface-Immobilized Double-Stranded DNA Using a Metallointercalator and Catalytic Voltammetry

Determination of Surface-Immobilized Double-Stranded DNA Using a Metallointercalator and Catalytic Voltammetry

Enhanced electrochemical activity of redox-labels in multi-layered protein films on indium tin oxide nanoparticle-based electrode

Simple and Ultrasensitive Chemically Amplified Electrochemical Detection of Ferrocenemethanol on 4-Nitrophenyl Grafted Glassy Carbon Electrode

Contact Info

Product

Resources

About