Speciation of phytate ion in aqueous solution. Protonation constants and copper(II) interactions in NaNO3aq at different ionic strengths

Solubility and acid–base properties of concentrated phytate in self-medium and in NaClaq at T=298.15K

“…The protonation constants determined in several supporting electrolytes, and in a wide range of ionic strengths, were already reported in previous papers [7,8,10,11,[27][28][29][30]. It is known that the ligand concentration may influence strongly the speciation of phytate.…”

“…In turn, the speciation is linked to the acid-base properties and the solubility of this molecule. For these reasons, we undertook a systematic study on this topic, for a better definition of the chemistry of the phytate ion [7][8][9][10][11]. This study was performed both in NaCl aq , because sodium and chloride are the most abundant ions in the environment, and in self-medium, namely in solutions that do not contain supporting electrolyte, and where the ionic strength values are due to the dissociation of phytic acid and sodium phytate.…”

Potentiometric Determination of Phytic Acid and Investigations of Phytate Interactions with Some Metal Ions

“…4), which required an addition of an excess of alkali metal (≥ 1.0 M) into titration solution. Whilst other of numerous research groups dealing with the protonation and/or metal complexation equilibria of phytates 15,[24][25][33][34] reported on an "alkalimetric/acidimetric" standardization of the ligand concentrations, or by elemental analysis 35 or simply used commercialy supplied chemicals without any proof of its purity.…”

The effect of the tetraalkylammonium salts on the protonation thermodynamics of the phytate anion

“…The influence of the ions of the supporting electrolyte has not been deeply analyzed in the past. This research group published the phytate protonation constants in different media, considering also the protonation in self medium and the formation of binuclear protonated species at c Phy > 12 mmol dm À3 [23][24][25][26][27][28][29]. Usually, tetraalkylammonium salts have been widely used as supporting electrolytes in the studies of acid-base properties and ligand-metal complexation.…”