| Popis |
Thirty years ago the theory of elimination polarography (EP) and elimination voltammetry with linear scan (EVLS) was firstly published and experimentally verified [1-6]. The elimination procedure applied in both polarography as well as voltammetry can be considered as a mathematical model of the transformation of current-potential curves capable of eliminating some selected current components, while conserving others by means of elimination functions. While the elimination functions in EP use the differential dependence of a current component on time, the EVLS works on the basis of the different dependence of current components (diffusion, charging and kinetic) on the scan rate. Thereafter, the chosen EVLS function needs two or three voltammetric (LSV or CV) curves measured at different scan rates only. Due to longer time and experimental demands of elimination polarography, EVLS has been achieving greater development and usage during last decade. To this date it has found applications not only in electroanalysis, but also in studying electrode processes of inorganic and organic electroactive substances at mercury, silver and/or graphite electrodes [7-35]. For fully adsorbed electroactive species the function eliminating charging and kinetic current components, and conserving the diffusion current component, yields the specific, sensitive and well developed peak-counterpeak (p-cp) signal [7,8,16]. This signal, usually 10-20 times higher than corresponding measured voltammetric peak, is successfully employed in the analysis of nucleic acids and short homo- or hetero-deoxyoligonucleotides (ODNs) containing adenine and cytosine [10,15,17,19,21,22,33,34]. Moreover, it has been shown that the EVLS in combination with adsorptive stripping procedure is a promising tool for achieving very good resolution of electrode processes, for qualitative and quantitative analysis of ODNs and their components, as well as for the identification of ODN structures [10,15,17,19,21,22,33,34].
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