Sensitive spectrophotometric method for the determination of ethylenediaminetetraacetic acid in foods

Abstract

A sensitive spectrophotometric method for the determination of ethylenediaminetetraacetic acid (EDTA) in foods is described. The method involves the reaction of EDTA with Fe3+ to produce the EDTA-Fe chelate, followed by the removal of excess of Fe3+ by a chelate extraction technique using chloroform and N-benzoyl-N-phenylhydroxylamine and the formation of a chromophore with 4,7-diphenyl-1,10-phenanthroline-disulfonic acid. The calibration graph was linear in the range 0.5-40.0 micrograms cm-3 of EDTA with a slope of 21.1. The relative standard deviation at 10 micrograms cm-3 of EDTA was 1.6% (n = 10). There was no interference from most of the common ingredients of commercial foods. More than 90% of EDTA added at two levels was recovered from real samples. The method was applied to the determination of EDTA in various foods, and the results obtained were compared with those given by high-performance liquid chromatography.

EDTA leaching of Cu contaminated soil using electrochemical treatment of the washing solution

“…3). In accordance with previous observations [17] the percentage of Cu removal did not follow the increase in EDTA concentration. Cu and other heavy metals are present in soil in various chemical forms and bound to different soil fractions.…”

“…Samples of washing and soil rinsing solution were filtrated (filter paper grade 391, 84 g m −2 ) and EDTA determined spectrophotometrically according to the procedure of Hamano et al [17].…”

Using electrocoagulation for metal and chelant separation from washing solution after EDTA leaching of Pb, Zn and Cd contaminated soil

“…Samples of washing and soil rinsing solution were centrifuged at 2880 × g for 30 min and EDTA determined spectrophotometrically according to the procedure of Hamano et al [25].…”

Electrochemical separation and reuse of EDTA after extraction of Cu contaminated soil

“…The concentration of EDTA was determined spectrophotometrically according to the procedure of Hamano et al [15].…”