An interfacial equilibria model for the electrokinetic properties of a fat emulsion. Part II: Magnesium, zinc and proton interactions with the interface

Abstract

The semi-empirical thermodynamic model reported in an earlier paper (Hallet a/., 1991) is further developed to describe the zeta potential behaviour of an intravenous fat emulsion in the presence of magnesium and zinc cations. The effect of interfacial protonation is also explored. We have now established that a previously reported formation constant for the calcium interaction is actually a conditional value and together with the new data for zinc and magnesium, overall formation constants are calculated.

An interfacial equilibria model for the electrokinetic properties of a fat emulsion. Part III: A predictive computer model

“…The resulting estimated formation constants are included in Table 3. The species profile of the phospholipid reported in our earlier work (Gaskin et al, 1993) indicates that above pH 7 the pld2-species becomes significant. This is evident in the electrokinetic results with a sharp decrease in the charge density and zeta potential.…”

“…The protonation constants for pld 2 -and the formation constants for the interaction of Hpld-with calcium, magnesium and zinc have been reported in our previous papers (Hall et al, 1991;Gaskin et al, 1993) and are listed in Table 3. The formation constants for the species MnHpld+, CuHpld+, and FeHpld 2 + are estimated in the present study.…”