Electrocatalytic and Analytical Responses of 10-Methylphenothiazine Toward Reduced Glutathione

Gong, Xing; Li, Hu‐lin

doi:10.1149/1.1393181

Cited by 25 publications

(12 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A series of modified electrodes have been used based on enzymes [21,22], organometallic compounds [23,24], organic compounds [25], tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) complex [26], etc. [27].…”

Section: Introductionmentioning

confidence: 99%

Electrocatalytic oxidation of glutathione at carbon paste electrode modified with 2,7-bis (ferrocenyl ethyl) fluoren-9-one: application as a voltammetric sensor

2009

View full text Add to dashboard Cite

Electrooxidation of glutathione (GSH) was studied at the surface of 2,7-bis (ferrocenyl ethyl) fluoren-9-one modified carbon paste electrode (2,7-BFEFMCPE). Cyclic voltammetry (CV), double potential-step chronoamperometry, and differential pulse voltammetry (DPV) were used to investigate the suitability of this ferrocene derivative as a mediator for the electrocatalytic oxidation of GSH in aqueous solutions with various pH. Results showed that pH 7.00 is the most suitable pH for this purpose. At the optimum pH, the oxidation of GSH at the surface of this modified electrode occurs at a potential of about 0.410 V versus Ag|AgCl|KCl sat . The kinetic parameters such as electron transfer coefficient, a = 0.61, and rate constant for the chemical reaction between GSH and redox site in 2,7-BFEFMCPE, k h = 1.73 9 10 3 cm 3 mol -1 s -1 , were also determined using electrochemical approaches. Also, the apparent diffusion coefficient, D app , for GSH was found to be 5.0 9 10 -5 cm 2 s -1 in aqueous buffered solution. The electrocatalytic oxidation peak current of GSH showed a linear dependence on the glutathione concentration, and linear calibration curves were obtained in the ranges of 5.2 9 10 -5 M to 4.1 9 10 -3 M and 9.2 9 10 -7 M to 1.1 9 10 -5 M with cyclic voltammetry and differential pulse voltammetry methods, respectively. The detection limits (3r) were determined as 1.4 9 10 -5 M and 5.1 9 10 -7 M for the CV and DPV methods, respectively. This method was also examined as a selective, simple, and precise new method for voltammetric determination of GSH in real sample such as hemolysed erythrocyte.

show abstract

Section: Introductionmentioning

confidence: 99%

Electrocatalytic oxidation of glutathione at carbon paste electrode modified with 2,7-bis (ferrocenyl ethyl) fluoren-9-one: application as a voltammetric sensor

2009

View full text Add to dashboard Cite

show abstract

“…Cathodic stripping techniques based upon the accumulation and subsequent reduction of mercury -thiol complexes at mercury electrodes have been extensively studied [17 -25], however, the toxicity of mercury makes this approach unfavorable. The oxidation of thiols at solid electrodes has found fewer advocates but increasing interest in electrocatalysts such as phthalocyanine derivatives [26 -30], organic mediators [31,32], or enzymes [33] has begun to stimulate more interest in this important area. Other strategies rely on the reaction of quinones with reduced sulfur functionalities as a possible detection mechanism for various thiols of biomedical significance (principally cysteine, glutathione and albumin) [34 -36].…”

Section: Introductionmentioning

confidence: 99%

Electrochemical Reduction of Ellman's Reagent: A Novel Selective Detection Protocol for Thiol Compounds

et al. 2007

View full text Add to dashboard Cite

Herein we detail a novel approach to the detection of total sulfhydryl thiol species based on an electrochemical adaptation of the classical Ellmans reaction. The ability to electrochemically reduce the nitro moieties of both the parent 5,5-dithiobis(2-nitrobenzoic acid) (DTNB) and the resulting 5-thio-2-nitrobenzoic acid (TNBA) species provides a selective means of detecting thiol compounds. The use of the reductive sweep means that electrode passivation as a result of oxidative electrochemical procedures can be avoided and the selectivity improved through positioning the analytical signal within a region where few interferences reside. The electrochemical protocol enables the detection of the thiols in both acidic and basic media, which the colorimetric method is unable to do.

show abstract

“…The use of bare electrode for electrochemical detection of lmethionine and l-cystine and thiols have a number of limitations, such as low sensitivity and reproducibility, high overpotential for oxidation, the slow electron transfer reaction and low stability over a wide range of solution compositions. Many transfer mediators such as quinones [4,5], lead ruthenate [6], cerium hexachloroplatinate [7], multivanadium substituted polyoxometalate [8], Prussian blue [9], copper hexacyanoferrate [10], phenothiazine derivatives [11], and octacyanomolybdate(V) [12] have been used for electrocatalytic oxidation of thiols. Compton and co-workers reviewed the electrochemical methods based on different modified electrodes for thiols detection [13].…”

Section: Introductionmentioning

confidence: 99%

Electrocatalytic Oxidation of Sulfur Containing Amino Acids at Renewable Ni‐Powder Doped Carbon Ceramic Electrode: Application to Amperometric Detection L‐Cystine, L‐Cysteine and L‐Methionine

Salimi

Roushani

2006

Electroanalysis

View full text Add to dashboard Cite

A sol-gel technique was used here to prepare a renewable carbon ceramic electrode modified with nickel powder. Cyclic voltammograms of the resulting modified electrode show stable and a well defined redox couple due to Ni(II)/ Ni(III) system with surface confined characteristics. The modified electrode shows excellent catalytic activity toward l-cystine, l-cysteine and l-methionine oxidation at reduced overpotential in alkaline solutions. In addition the antifouling properties at the modified electrode toward the above analytes and their oxidation products increases the reproducibility of results. l-cystine, l-cysteine and l-methionine were determined chronoamperometricaly at the surface of this modified electrode at pH range 9 -13. Under the optimized conditions the calibration curves are linear in the concentration range 1 -450 mM, 2 -90 mM and 0.2 -75 mM for l-cystine, l-methionine and l-cysteine determination, respectively. The detection limit and sensitivity were 0.64 mM, 3.8 nA/ mM for l-cystine, 2 mM, 5.6 nA/ mM for l-methionine and 0.2 mM and 8.1 nA/mM for l-cysteine. The advantageous of this modified electrode is high response, good stability and reproducibility, excellent catalytic activity for oxidation inert molecules at reduced overpotential and possibility of regeneration of the electrode surface by potential cycling for 5 minutes. Furthermore, the modified electrode has been prepared without using specific reagents. This sensor can be used as an amperometric detector for disulfides detection in chromatographic or flow systems.

show abstract

Electrocatalytic and Analytical Responses of 10-Methylphenothiazine Toward Reduced Glutathione

Cited by 25 publications

References 20 publications

Electrocatalytic oxidation of glutathione at carbon paste electrode modified with 2,7-bis (ferrocenyl ethyl) fluoren-9-one: application as a voltammetric sensor

Electrocatalytic oxidation of glutathione at carbon paste electrode modified with 2,7-bis (ferrocenyl ethyl) fluoren-9-one: application as a voltammetric sensor

Electrochemical Reduction of Ellman's Reagent: A Novel Selective Detection Protocol for Thiol Compounds

Electrocatalytic Oxidation of Sulfur Containing Amino Acids at Renewable Ni‐Powder Doped Carbon Ceramic Electrode: Application to Amperometric Detection L‐Cystine, L‐Cysteine and L‐Methionine

Contact Info

Product

Resources

About