Determination of nitrate in natural waters by voltammetry at a stationary mercury drop electrode

Programmed‐potential voltammetric determination of nitrate at a static mercury drop electrode in natural waters and soil extracts

“…Special care has to be taken in selection of the supporting electrolyte (which must be free of any trace of nitrate). In agreement with previous results [2] The potential range for electroreduction of nitrate in these media is below -1 V (vs. Ag/AgCl) and depends both on the concentration level of nitrate in the solution and on the previous history of the SMDE used [2]. Special treatment of the SMDE may increase the nitrate reduction current even at very low concentrations of nitrate.…”

“…The calibration dependences (linear between 1 and 1500 pM nitrate with linear regression coefficient of 0.999 when analyzing natural water samples containing humic substances) as well as the favorable effect of natural surface active substances (humic and fulvic acids) are described and discussed in our previous work where somewhat different, less convenient treatment for modification of the electrode surface is used [2]. Nevertheless, in the two cases the results are identical.…”

“…The rapid growth of stripping techniques and adsorptive voltammetric methods using preconcentrating and/or in situ modified electrodes has been enabled by the easy application of a variety of electrode pretreatment and presweep steps. In this context the way nitrate was determined by second-sweep cyclic voltammetry at a stationary mercury drop electrode [2] (with repeatedly manually switched potential) may be regarded as cumbersome, despite the adequate sensitivity and advantages presented in the cited work.…”

“…Both the method mentioned [2] and the proposed improved version make use of the catalytic effect of hydroxyl anions on the electrochemical reduction of nitrate in the presence of trivalent cations [3,4].…”

Voltammetric investigation of complex growth media at a bare glassy carbon electrode: A case study of oxytetracycline

“…One of the distinct advantages of voltammetric methods of analysis is that it is not limited by solution turbidity [7,8]. Surprisingly few studies have explored the application of voltammetric methods as a viable alternative for bioprocess control measurement.…”