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Updated: Aug 17, 2026

TD-DFT Guided Advanced E-Eye Sensing Technique for On-site Quantification of Fe, Cr, F, and As in the Environmental, Biological, and Food Samples
09:51

TD-DFT Guided Advanced E-Eye Sensing Technique for On-site Quantification of Fe, Cr, F, and As in the Environmental, Biological, and Food Samples

Published on: September 19, 2025

Better stability of total homocysteine measurement with sodium fluoride than with EDTA

Fleur Wolff1, Philippe Gausset, Jean Vanderpas

  • 1Department of Clinical Biology, Hôpital César de Paepe, Brussels, Belgium. fleur.wolff@chu-brugmann.be

Clinical Laboratory
|July 5, 2005
PubMed

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In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a result, EDTA...
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EDTA: Indirect and Alkalimetric Titration

Unlike direct titration, back-titration, and displacement titration, indirect titration is an EDTA titration method for quantifying anions. In the indirect titration method, anions are precipitated as their insoluble salts with excess metal ions. The filtrate containing the excess metal ions is directly titrated with standard EDTA until the endpoint is achieved. Another approach involves extracting the metal ion and back-titrating with standard EDTA to obtain the endpoint. In this way, the...
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