What is micellar electrokinetic chromatography used for?
Micellar electrokinetic chromatography is a modified version of capillary electrophoresis which is used to separate a wide range of molecules, from inorganic ions to large biopolymers.
How does micellar electrokinetic capillary chromatography work?
In micellar electrokinetic capillary chromatography, surfactants are added to the buffer solution in concentration above their critical micellar concentrations, consequently micelles are formed; micelles that undergo electrophoretic migration like any other charged particle.
Why can micellar electrokinetic chromatography be used to separate neutral molecules?
The micelles are highly charged and move in the electric field. They can interact with molecules of analytes, even when they are neutral, and form transient associations. In this way the analytes obtain an electrophoretic movement and can be separated if their interaction constants are different.
What is capillary zone electrophoresis used for?
Capillary zone electrophoresis (CZE) is a technique successfully used for the separation of proteins, peptides, and nucleic acids. Other applications where CZE may be useful include analysis of inorganic anions and cations, such as those typically separated by ion chromatography.
What does cIEF measure?
Capillary isoelectric focusing (cIEF) is a high-resolution analytical technique that allows the separation of protein/peptide mixtures, protein glycoforms and other charge variants, based on their isoelectric point (pI).
What is capillary gel electrophoresis?
Capillary gel electrophoresis (CGE) is a CE version of slab-gel electrophoresis and is used for size-based separation of biological macromolecules such as oligonucleotides, DNA fragments, and proteins. In CGE, cross-linked or non-cross-linked sieving matrices are employed.
What is electroosmotic flow in capillary electrophoresis?
Electroosmotic flow is observed when an electric field is applied to a solution in a capillary that has fixed charges on its interior wall. The mobile cation layer is pulled in the direction of the negatively charged cathode when an electric field is applied.
What is electrokinetic injection capillary electrophoresis?
There are two commonly used injection methods for CE: hydrodynamic and electrokinetic. Hydrodynamic injection is accomplished by the application of a pressure difference between the two ends of a capillary. Electrokinetic injection is performed by simply turning on the voltage for a certain period of time.
What is capillary Isotachophoresis?
Capillary isotachophoresis (cITP) is a technique in which solutes are focussed along the capillary based on their mobility compared to “leading” and “terminating” added solutes which have fast and slow mobilities, respectively.
Which detectors are used in capillary electrophoresis?
This chapter presents a fundamental overview over current detection systems used in capillary electrophoresis with the focus on modern trends. Attention is paid mainly to UV-Vis absorption spectrometric, fluorescence, amperometric, contactless conductivity, and electrochemiluminiscence detectors.
What causes electroosmotic flow?
Electroosmotic flow is caused by the Coulomb force induced by an electric field on net mobile electric charge in a solution. The resulting flow is termed electroosmotic flow.
How is micellar electrokinetic chromatography used in analytical chemistry?
Micellar electrokinetic chromatography (MEKC), is a chromatography technique, used in analytical chemistry. It is a modification of capillary electrophoresis (CE), where the samples are separated by differential partitioning between micelles (pseudo-stationary phase) and a surrounding aqueous buffer solution (mobile phase).
How is micellar electrophoresis based on analyte partitioning?
Micellar electrokinetic electrophoresis is based on the analyte partitioning between the aqueous and micellar phase. When an analyte is added to the solution, a part of it incorporates into the micelle and migrates along with it.
How are neutral compounds separated in micelle electrophoresis?
Although micellar electrokinetic electrophoresis was initially used to separate neutral compounds, as it separates both neutral and charged compound with equal electrophoretic abilities, it is used for both now. The compounds in this method can be separated both on the basis of electrophoretic mobility and solute partitioning in the micelle.
How is the electrophoretic velocity of a micelle defined?
The micelle velocity is defined by: is the electrophoretic velocity of a micelle. is the total moles in the aqueous phase. The retention time of a solute should then be within the range: