Thermodynamics for proton binding of phytate in KNO3(aq) at different temperatures and ionic strengths

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 interaction between K + and Phy 12À , noticed and quantified elsewhere [24,29], lowers the values of the apparent protonation constants. Beyond these considerations, the protonation constants determined in (C 2 H 5 ) 4 NI are slightly higher than those in (CH 3 ) 4 NCl.…”

“…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.…”

On the interaction of phytate with proton and monocharged inorganic cations in different ionic media, and modeling of acid-base properties at low ionic strength

“…These properties, together with many other possible use of phytate (e.g., in electrochemistry), are well described in many books and papers (e.g., [7][8][9][10][11][12][13][14][15][16][17][18] and references therein). This research group has studied the acid-base and the binding properties of phytic acid in many experimental conditions [12,[19][20][21][22][23][24][25][26][27]. Recently, in Bretti et al [27] (and references therein), the protonation of phytate in weakly interacting media, such as the tetraalkylammonium salts, has been analyzed together with the most reliable literature data.…”

“…As regards interacting ionic media, such as Na + or K + containing salts, in table 1 the most reliable protonation data in Na + and K + media are reported http://dx.doi.org/10.1016/j.jct.2015.06.012 0021-9614/Ó 2015 Elsevier Ltd. All rights reserved. [19,20,26,[28][29][30][31][32][33][34][35]. Note that in the table the data are reported in the molar concentration scale because it is more correct when comparing results obtained in different ionic media [36], however, dealing with the electrolytes used in this work at low ionic strength (I 6 0.15 mol Á dm À3 ), molar and molal concentration scales are practically equivalent.…”