The polarographic behaviour of ethyleneglycol-bis-β-aminoethylether-N,N,N′,N′-tetraacetic acid

✍ Scribed by B. Fleet; Soe Win; T.S. West

• Publisher: Elsevier Science
• Year: 1969
• Weight: 266 KB
• Volume: 21
• Category: Article
• ISSN: 0022-0728
• DOI: 10.1016/s0022-0728(69)80332-3

✦ Synopsis

The complexone ethyleneglycol-bis-fi-aminoethylether-N,N,N',N'-tetraacetic acid (EGTA) first introduced by Schwarzenbachl has proved to be a selective analytical reagent for the determination of calcium in the presence of magnesium 2 and cadmium in the presence of zinc 3. Potentiometric studies of the compound using a mercury electrode have been carried out by Schmid and Reilley 4, but no systematic study of its polarographic behaviour has so far been reported although a few analytical applications have been made 5'6.

A study of the polarographic behaviour of ethylenediamine-N,N,N',N'-tetraacetic acid (EDTA) was first made by Matyska and K6ssler 7 and later by Goffart et al. 8. The results of the two groups of workers disagree significantly and a few years later a revised paper by Matyska and coworkers 9 appeared in which a study of the polarographic behaviour of 1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid was also included: The present paper describes a study of the anodic polarographic behaviour of EGTA which is attributed to the formation of a mercury complexonate. The latter has been identified and its stability constant determined at different pHvalues.

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