A. J. Barnard, W. C. Broad, H. Flaschka
Feb 1, 1959
Citations
0
Influential Citations
2
Citations
Quality indicators
Journal
Microchemical Journal
Abstract
Over eleven hundred papers have appeared within the last twelve years relevant to the use of ethylenediaminetetraacetic acid and its salts (EDTA) in analytical chemistry. This extensive literature makes clear the need for reviews and suggests the desirability of critical studies. Flaschka in 1953l and in 19552 reviewed the use of EDTA in analysis with emphasis on the EDTA titration. Monographs on this titration have been written by Schwarzenbach3 and by Ueno4; other monographs treating this titration as well as other analytical uses for EDTA are by Pribi15 and by Welcher.6 The compilers of the present paper have reviewed the general nature of the EDTA titration and the various methods of endpoint detection including the use of metal indicators.’ In a further review they have considered the application of the titration to over 50 elements.8 Further, Flaschka has selectively reviewed the use of EDTA as a masking agent in analytical chemistry.g The present paper, which is a continuation of these review activities, delineates some applications for EDTA as a reagent in micro analysis. It should be noted that both ethylenediaminetetraacetic acid and its anion, ethylenediaminetetraacetate, are commonly referred to as EDTA. However, as the free acid is not very soluble in water, a stock EDTA solution is often prepared by dissolving the free acid in caustic or occasionally in ammoniacal solution. Alternatively, the disodium salt dihydrate is dissolved in water. Hence the term “EDTA” in the analytical literature usually implies the anion form. The theoretical basis for the use of EDTA as an analytical reagent was first studied by Schwarzenbach and co-workers and has been ex* Based in part on a talk before the 13th Annual Symposium, Metropolitan Microchemical Society, New York, March 1958.