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Preservative properties of Calamintha officinalis essential oil with and without EDTA

A Nostro1, M A Cannatelli, I Morelli

  • 1Dipartimento Farmaco-Biologico, Sezione Microbiologia, Facoltà di Farmacia, Università di Messina, Italy. atnostro@pharma.unime.it

Letters in Applied Microbiology
|October 23, 2002
PubMed
Abstract

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EDTA titrations are usually carried out in highly basic conditions, where the fully deprotonated form of EDTA, Y4−, actively complexes with the free metal ions in the solution. Several metal ions precipitate as hydrous oxide (hydroxides, oxides, or oxyhydroxides) under these conditions, lowering the concentration of free metal ions in the solution. For this reason, auxiliary complexing agents or ligands such as ammonia, tartrate, citrate, or triethanolamine are used in EDTA titrations to...
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Different methods, such as visual observance of metal-ion indicators, spectroscopic techniques, and potentiometric methods, can determine the endpoint of an EDTA titration.
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Complexometric EDTA Titration Curves

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