Conductivity and electrophoretic mobility of dilute ionic solutions

Characterization of gold nanoparticles with different hydrophilic coatings via capillary electrophoresis and Taylor dispersion analysis. Part I: Determination of the zeta potential employing a modified analytic approximation

“…The widely used numerical calculations according to O'Brien and White [10] neglect the influence of Brownian motion, also Ohshima's approximate analytic expression [11]. Very recently, Allison et al [60] demonstrated that theory developed for colloidal particles (denoted ''large ions'') works well also for small ions if Brownian motion (commonly ignored in the large ion model) is taken into account and an ion exclusion layer is included. Interestingly, Wiersema [61] and Wiersema et al [9] already addressed this point.…”

Generalized polymer effective charge measurement by capillary isotachophoresis

“…This approach is well suited for small ions and nanoparticles (hardcore charged spheres) but is not yet applicable to polyelectrolytes due to the lack of suitable theoretical model. Numerical simulations can also be used [26][27][28][29][30][31] but these approaches are computationally time consuming and, as a consequence, limited so far to the study of oligomeric chains.…”

Specific ion effects on the electrophoretic mobility of small, highly charged peptides: A modeling study

“…Because these models have been discussed previously and since the technical details are of limited interest to most readers, a detailed description has been placed in the Supporting Information and only a brief discussion is presented here. Simply, the particle is modeled as a “small ion” of valence charge z j and effective radius, a j , where the mobility can be written as …”

“…, α, B , and B 1 are constants, which at a temperature of 298.15 K in an aqueous BGE are equal to 9.549 × 10 −18 m 3 /(V s), 3.286 × 10 9 (liter/(mole, m)), and 0.7817 (liter/mole) 1/2 , respectively. I is the ionic strength in moles/liter and S j represents a correction for the “relaxation effect” , which deals with the distortion of the ion atmosphere from equilibrium due to the imposition of an external flow and electric field on the model particle (see Supporting Information for details). This can be rearranged to yield …”