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Biomedical subjects

Ivana Sestáková

Publications and source records attributed to Ivana Sestáková.

2 recordsLinked to original sources

Electrochemical behavior of phytochelatins and related peptides at the hanging mercury drop electrode in the presence of cobalt(II) ions.

Direct current voltammetry and differential pulse voltammetry have been used to investigate the electrochemical behaviour of two phytochelatins: heptapeptide (gamma-Glu-Cys)3-Gly and pentapeptide (gamma-Glu-Cys)2-Gly, tripeptide glutathione gamma-Glu-Cys-Gly and its fragments: dipeptides Cys-Gly and gamma-Glu-Cys at the hanging mercury drop electrode in the presence of cobalt(II) ions. Most interesting results were obtained with direct current voltammetry in the potential region of -0.80 V up to -1.80 V. Differential pulse voltammetry of the same solutions of Co(II) with peptides gives more complicated voltammograms with overlapping peaks, probably in connection with the influence of adsorption at slow scan rates necessarily used in this method. However, in using Brdicka catalytic currents for analytical purposes, differential pulse voltammograms seem to be more helpful. Presented investigations have shown that particularly the prewave of cobalt(II) allows distinguishing among phytochelatins, glutathione, and its fragments.

Catalysis↗

Recent developments in quantification methods for metallothionein.

The metallothioneins (MT), a family of proteins with relatively low molecular weight (6-7 kDa), are characterised by the intrinsic presence of 20 cysteinyl groups in their structure, which confers unique metal binding properties to the molecule. Since MT are involved in biological roles, quantification of MT remains an important task. To date, a large number of determination methods have been developed. In this paper recent developments, from 1995 to the present, in methodology employed in quantification studies of total MT and MT polymorphism are described. Different fields were taken into consideration, such as (i) separation techniques and hyphenated systems, (ii) electrochemical methods, (iii) immunological methods and (iv) quantification of MT mRNA. The data presented are based on our own and published results. A brief overview of the use of metallothionein as a biomarker is included as a relevant example of the importance of MT quantification. Finally, general problems associated with determination and evaluation of obtained results within the above four topics are mentioned.

Animals↗