Journal: Electrophoresis

Article Title: Dynamic computer simulations of electrophoresis: 2010–2020

doi: 10.1002/elps.202100191

Figure Lengend Snippet: 2D simulation of ITP in the absence and presence of counterflow using COMSOL Multiphysics . (A) Anionic ITP of fluorescein (analyte with a high diffusivity) and R‐phycoerythrin (RPE, analyte with a low diffusivity) without application of counterflow. (B) Anionic ITP of fluorescein under stationary counterflow with (i) a parabolic counterflow profile and molecular diffusivity and (ii) a flat counterflow profile and Taylor‐Aris effective diffusivity. (C) same as (B) but for RPE. (D) Schematic illustration of electromigration of an analyte counteracted by a parabolic counterflow. The leading electrolyte was composed of 10 mM HCl and ethanolamine (pH 9.5) and the terminating electrolyte comprised 20 mM barium hydroxide. A 75 μm id coated fused‐silica capillary with minimized EOF served as separation space. The applied current density was 226.4 A/m 2 and the average flow velocity was 1.45 × 10 −4 m/s. Other input data are given in . The anode is to the left. From ref. ; copyright Wiley‐VCH GmbH; reproduced with permission.

Article Snippet: Very recently, a 2D mathematical model of electromigration that considers the deviation from electroneutrality in the diffuse layer of the double layer when the liquid phase is composed of a solution of weak electrolytes of any valence and complexity was developed, integrated into COMSOL Multiphysics and applied to the prediction of electromigration in nanochannels [ ].

Techniques:

Journal: Electrophoresis

Article Title: Dynamic computer simulations of electrophoresis: 2010–2020

doi: 10.1002/elps.202100191

Figure Lengend Snippet: Focusing of an anionic analyte within an inverse electromigration dispersion profile . Schematic representation of pH, conductivity κ , velocity v , and analyte concentration c A along the migration coordinate for an anionic electromigration dispersion profile after time t evolving from a sharp initial boundary between the leading zone L and the terminating zone T. The anionic analyte focuses on the profile at point x A0 where its electrophoretic velocity v A is equal to v j of the gradient. EMD refers to electromigration dispersion. The anode is to the right. From ref. ; copyright Wiley‐VCH GmbH; reproduced with permission.

Article Snippet: Very recently, a 2D mathematical model of electromigration that considers the deviation from electroneutrality in the diffuse layer of the double layer when the liquid phase is composed of a solution of weak electrolytes of any valence and complexity was developed, integrated into COMSOL Multiphysics and applied to the prediction of electromigration in nanochannels [ ].

Techniques: Dispersion, Concentration Assay, Migration

Journal: Electrophoresis

Article Title: Dynamic computer simulations of electrophoresis: 2010–2020

doi: 10.1002/elps.202100191

Figure Lengend Snippet: Focusing of weak acids within an inverse electromigration dispersion profile predicted by SIMUL5 . Computer simulated concentration profiles of 12 analytes consisting of weak acids with an ionic mobility of 30 × 10 – 9 m 2 /Vs and with pKa values between 4.5 and 10 (peak labels) after 10 s of electrophoresis time with an applied voltage of 2500 V across a separation column of 25 mm length. The leading electrolyte was composed of 15.2 mM maleic acid and 21.7 mM 2,6‐lutidine (pH 5.81) whereas the trailing electrolyte contained 2 mM maleic acid and 27.6 mM 2,6‐lutidine (pH 7.53). The sample contained 2 × 10 – 8 M of each analyte and leading electrolyte, was placed between the two electrolytes at the cathodic column side and had a length of 1.25 mm. The distributions of 2,6‐lutidine (Lut, lower panel), conductivity and pH (both upper panel) are presented for the same time point. The anode is to the right. From ref. ; copyright Elsevier; reproduced with permission.

Article Snippet: Very recently, a 2D mathematical model of electromigration that considers the deviation from electroneutrality in the diffuse layer of the double layer when the liquid phase is composed of a solution of weak electrolytes of any valence and complexity was developed, integrated into COMSOL Multiphysics and applied to the prediction of electromigration in nanochannels [ ].

Techniques: Dispersion, Concentration Assay, Electrophoresis

Journal: Electrophoresis

Article Title: Dynamic computer simulations of electrophoresis: 2010–2020

doi: 10.1002/elps.202100191

Figure Lengend Snippet: Complexation can be a source of electromigration dispersion . Comparison of the experimental (upper panels) and simulated (lower panels; SIMUL5complex) electropherograms for R‐flurbiprofen as the analyte with (A) β‐CD, (B) heptakis(2,6‐di‐O‐methyl)‐β‐CD, and (C) heptakis(2,3,6‐tri‐O‐methyl)‐β‐CD as the complexing agent. The complexation constants were 4037, 4800, and 552 L/mol, respectively, and the mobilities of the complexes were 8.82 × 10 – 9 , 7.54 × 10 – 9 , and 6.50 × 10 – 9 m 2 /Vs, respectively. The BGE was composed of 50 mM Tris and 50 mM tricine having an experimental pH of 8.13 and an ionic strength of 25.76 mM. The samples contained 0.3 mM R‐flurbiprofen. The peaks are labeled with the concentration of the selector used in the BGE. From ref. ; copyright Elsevier; reproduced with permission.

Article Snippet: Very recently, a 2D mathematical model of electromigration that considers the deviation from electroneutrality in the diffuse layer of the double layer when the liquid phase is composed of a solution of weak electrolytes of any valence and complexity was developed, integrated into COMSOL Multiphysics and applied to the prediction of electromigration in nanochannels [ ].

Techniques: Dispersion, Comparison, Labeling, Concentration Assay