Sono-Adsorptive Stripping Voltammetry: Its Application to the Analysis of Metals and Organic Compounds in Aqueous Media

Abstract

The effect of applying ultrasound during the preconcentration step of the adsorptive stripping voltammetry (AdSV) analysis of vanadium, nickel and riboflavin is presented. First, the sono-AdSV determination of vanadium(V) was achieved by interfacial accumulation of its catechol complex under ultrasound applied from an ultrasonic probe opposite a mercury-coated copper electrode. Ultrasound was found to increase the speed at which the complex was deposited onto the mercury surface in comparison with silent conditions. Similar analytical performances to those described in the literature were obtained for shorter preconcentration times under ultrasound. Second, the effect of ultrasound on the AdSV analysis of Ni 2+ was studied using a mercury film plated in situ on a glassy carbon electrode. Dimethylglyoxime was used as the complexing agent. The loss of mercury due to sonication is shown to decrease the sensitivity of the method. Third, the sono-AdSV analysis of an organic compound, riboflavin, was investigated. Accumulation of riboflavin was conducted both in a preplated mercury film electrode and on a glassy carbon substrate. Faster rates of adsorption were observed for riboflavin under the presence of ultrasound. In addition the AdSV analysis of riboflavin also benefits from surface activation of the glassy carbon electrode due to cleaning of its surface by the use of ultrasound. In this respect, partial removal of lumichrome, a less adsorbing species than riboflavin under these conditions and a product of riboflavin photolysis, has been observed under sonication.

Metals in alcoholic beverages: A review of sources, effects, concentrations, removal, speciation, and analysis

“…Reticulated vitreous carbon (RVC) is covered with Hg prior to use in ASV (Mayer et al, 2003;Macca et al, 1997;Marken et al, 1997;Ostapezuk et al, 1997;Agra-Gutierrez and Compton, 1998).…”

Development of a sensitive and selective Riboflavin sensor based on carbon ionic liquid electrode

“…However, these methods are usually tedious, time consuming and involve complicated procedures and expensive instrumentation. Due to the high sensitivity and selectivity of electrochemical methods, several methods have been developed for the determination of Riboflavin [8][9][10][11]. Simultaneous determination of Riboflavin and other soluble vitamins has been performed by electrochemical methods [12][13][14][15].…”

Kinetics of Electrocrystallization of PbO2 on Glassy Carbon Electrodes. Influence of the Electrode Rotation

“…Both processes can be carried out in quiescent solution, however, for many applications it is important that the electrode is located within a flow system to permit continuous monitoring and to enhance the speed of the analysis. Nowadays, different approaches to increase the mass transport to the surface electrode are being investigated: ultrasonic field [9], wall-jet [10] and channel electrode [11] geometries. Accordingly, the question arises as to whether the introduction of convection as a dominating contribution to the transport leads to significant changes in the process.…”