Thiourea electrochemical determination

The various oxidation states of sulfur have been determined by polarography. The electrochemical oxidation of sulfide ions in aqueous solution may lead to the production of elementary sulfur, polysulfides, sulfate, dithionate, and thiosulfate, depending on the experimental conditions. Disulfides, sulfoxides, and sulfones are typical polarographically active organic compounds. It is also found that thiols (mer-captans), thioureas, and thiobarbiturates facilitate oxidation of Hg resulting thus in anodic waves. 

Figure 2 exhibits the use of this type of electrode for the determination of thiourea (Figure 2a), methylthiouracil (Figure 2b) and 6-mercapto-purine (Figure 2d). Oxidation of the compounds occurs at less positive potentials with a high rate of electron transfer. Thiamazole (Figure 2c) can also be analyzed using the EPCM but its electrochemical behaviors are very similar to those obtained with the conventional one.

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