Continuous Counteracting Chromatographic Electrophoresis

Ivory, Cornelius F.; Gobie, William A.

doi:10.1021/bp00001a004

Cited by 33 publications

(30 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reverse rate constant for each reaction was specified with the forward rate constant calculated using Eqs. (13)(14)(15). The magnitude of the reverse rate constant was determined based on the ability of the system to maintain equilibrium.…”

Section: Numerical Model Setup and Assumptionsmentioning

confidence: 99%

“…When used in conjunction with other orthogonal separation techniques, EGMs not only give an added separation dimension but can also serve as preconcentrators and prefractionators. Several EGMs have been developed including density gradient sedimentation [12] and counteracting chromatographic electrophoresis (CACE) [13][14][15], but the most commonly utilized EGM is IEF. In this case, separation occurs in the presence of a pH gradient.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of voltage degradation in dynamic field gradient focusing

Burke

Ivory

2008

Electrophoresis

Self Cite

View full text Add to dashboard Cite

Dynamic field gradient focusing (DFGF) is an equilibrium gradient method that utilizes an electric field gradient to simultaneously separate and concentrate charged analytes based on their individual electrophoretic mobilities. This work describes the use of a 2-D nonlinear, numerical simulation to examine the impact of voltage loss from the electrodes to the separation channel, termed voltage degradation, and distortions in the electric field on the performance of DFGF. One of the design parameters that has a large impact on the degree of voltage degradation is the placement of the electrodes in relation to the separation channel. The simulation shows that a distance of about 3 mm from the electrodes to the separation channel gives the electric field profile with least amount of voltage degradation. The simulation was also used to describe the elution of focused protein peaks. The simulation shows that elution under constant electric field gradient gives better performance than elution through shallowing of the electric field. Qualitative agreement between the numerical simulation and experimental results is shown. The simulation also illustrates that the presence of a defocusing region at the cathodic end of the separation channel causes peak dispersion during elution. The numerical model is then used to design a system that does not suffer from a defocusing region. Peaks eluted under this design experienced no band broadening in our simulations. Preliminary experimental results using the redesigned chamber are shown.

show abstract

Section: Numerical Model Setup and Assumptionsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Characterization of voltage degradation in dynamic field gradient focusing

Burke

Ivory

2008

Electrophoresis

Self Cite

View full text Add to dashboard Cite

show abstract

“…Earlier designs of preparative electrochromatography, mostly with a view to the size-exclusion chromatography, fixed the electrodes on the two ends of the column; that is, the electric field was applied in the axial direction [12 -18]. This mode of electrochromatography goes against the effective removal of Joule heat and electrolytic gases, which has been the major challenge in the scaling-up of preparative electrochromatography [18,19]. Later, Liu et al [20,21] introduced a five-compartment electrolyzer designed for preparative affinity, ion-exchange and hydroxylapatite chromatography.…”

Section: Introductionmentioning

confidence: 99%

High‐capacity purification of hen egg‐white proteins by ion‐exchange electrochromatography with an oscillatory transverse electric field

Yuan

Zhao

Dong

et al. 2006

J of Separation Science

View full text Add to dashboard Cite

Original PaperHigh-capacity purification of hen egg-white proteins by ion-exchange electrochromatography with an oscillatory transverse electric fieldThe ion-exchange electrochromatography with an oscillatory electric field perpendicular to the mobile-phase flow driven by pressure (pIEEC) was used to separate hen egg-white (HEW) proteins. The results were compared with those of normal ionexchange chromatography (IEC). The column was designed as three-compartment rectangular column of 2-mL with dimensions (length6width6depth) of 4061065 mm 3 and the electric field was applied across the direction of column width. Q Sepharose FF was packed into the central compartment as the chromatographic bed. It was confirmed that the dynamic binding capacity (DBC) of different proteins (ovotransferrin and ovalbumin) in the HEW solution increased 2.3 times when an oscillatory electric current of 30 mA at 1/20 Hz was applied in the transverse column direction. Then, the HEW proteins were separated by the pIEEC at loading amounts 2.3-fold higher than those by the IEC. When the feedstock of about one-third of the DBC was applied to the columns (i. e., 7 mL for the pIEEC and 3 mL for the IEC), similar separation efficiencies of the two chromatographic modes were achieved. Both the recovery yield and purity reached 73% to over 90%. The results indicate that the pIEEC is promising for high-capacity purification of proteins.

show abstract

“…Mathematical models for electrokinetic systems in literature describe heat-transfer effects (Vermeulen et al, 1971;Lynch and Saville, 1981;Datta et al, 1986;Yoshisato et al, 1986;Ivory and Gobie, 1990;Raj and Hunter, 1991). This article presents a modified electrochromatography system that minimizes Joule heating at electric field strengths up to 125 V/cm by heat dissipation through a cooling jacket (6°C) and use of a cooled, low ionic strength eluting buffer.…”

Section: Introductionmentioning

confidence: 99%