Exact electric field strength over the packed capillary electrochromatography column bed, theoretical considerations

Wei Guo1, Changhua Yang, Bingjiu Xu

  • 1Department of Analytical Chemistry, School of Pharmaceutical Sciences, Peking University, Beijing 100083, PR China.

Related Concept Videos

Column Efficiency: Plate Theory01:10

Column Efficiency: Plate Theory

Band broadening in a chromatography column is measured by its efficiency. This is determined by the number of theoretical plates (N). Theoretical plate theory states that a separation column consists of a continuous series of imaginary plates where solute equilibration occurs between stationary and mobile phases.
A higher number of theoretical plates signifies better column efficiency and improved separation capabilities. Plate height affects bandwidth and separation quality; it is inversely...
Column Efficiency: Rate Theory01:12

Column Efficiency: Rate Theory

The rate theory of chromatography provides quantitative insight into the shapes and widths of elution bands. These bands are based on the random-walk mechanism governing molecular migration within a column. The Gaussian profile of chromatographic bands arises from the cumulative effect of random molecular motions as they progress through the column.
During elution, a solute molecule experiences numerous transitions between stationary and mobile phases, exhibiting irregular residence times in...
Ion-Exchange Chromatography01:09

Ion-Exchange Chromatography

Ion-exchange chromatography, or IEC, is a technique for separating ions based on their affinity for the stationary phase. The stationary phase is a cross-linked polymer resin with covalently attached ionic functional groups. The functional groups can be either positively charged (cation exchangers) or negatively charged (anion exchangers). A cation exchanger consists of a polymeric anion and active cations, while an anion exchanger is a polymeric cation with active anions. The choice of...
Electrophoresis: Overview01:20

Electrophoresis: Overview

Electrophoresis is a powerful analytical separation technique that relies on the differential migration of charged species when subjected to an electric field. The core strength of electrophoresis lies in its ability to separate high-molecular-weight species in complex mixtures. It has found widespread use in biochemistry, molecular biology, and analytical chemistry, allowing the separation of compounds like amino acids, nucleotides, carbohydrates, and proteins with excellent resolution.
There...
Capillary Electrophoresis: Instrumentation01:20

Capillary Electrophoresis: Instrumentation

Capillary electrophoresis instrumentation typically consists of several key components. A high-voltage power supply generates the electric field necessary for the separation by connecting to an anode (the positively charged electrode) and a cathode (the negatively charged electrode) located in buffer reservoirs at each end of the capillary tube. The system includes a sample vial, a fused silica capillary tube coated with polyimide for mechanical strength through which the sample components...
Capillary Electrophoresis: Applications01:30

Capillary Electrophoresis: Applications

Capillary electrophoretic separations offer various modes, each with unique applications. These modes include capillary zone electrophoresis, capillary gel electrophoresis, capillary array electrophoresis, capillary isoelectric focusing, capillary isotachophoresis, micellar electrokinetic chromatography, and capillary electrochromatography.
Capillary zone electrophoresis (CZE) separates ionic components based on their electrophoretic mobility. It has been used to separate proteins, amino acids,...