Free solution capillary zone electrophoresis

The charge density of biomolecules is related to their electrophoretic mobility therefore, electrophoresis in a free solution capillary zone electrophoresis (CZE)) can be a method to separate biomolecules based on the charge density. The free solution electrophoretic mobility is a characteristic feature of each analyte, which is determined by the complicated balance among the electrical driving force on the analyte, electrical driving force on the counterions within the... 

Free solution electrophoresis (capillary zone electrophoresis). 

Currently, there are five major modes of operation of CE capillary zone electrophoresis (CZE), also referred to as free solution or free flow capillary electrophoresis micellar electrokinetic chromatography (MEKC) capillary gel electrophoresis (CGE) capillary isoelectric focusing (CIEF) and capillary isotachophoresis (CITP). Of these, the most commonly utilized capillary techniques are CZE and MEKC (Rabel and Stobaugh 1993 Issaq 1999 Smyth and McClean 1998). 

Electrophoresis can be classified on the basis of whether it is carried out as a free solution or on the support media. When support media are used, the technique is called zone electrophoresis. Capillary electrophoresis (CE), which is commonly used today, fits into the latter category, and at one time was called capillary zone electrophoresis. 

Capillary zone electrophoresis (CZE), also known as free-solution CE, is the most widely used mode of CE essentially because of its versatility. Protein separation in CZE is based on the differential electrophoretic mobility of the analytes. This mobility is primarily dependent on a protein s size and net charge, the charge-to-mass ratio. Solvent properties that influence the size and charge of a protein include pH, ionic strength, viscosity, and dielectric constant.67 Manipulation of these properties, most notably pH, dictates the selectivity in CZE. Maximizing the charge difference between two proteins via pH modification optimizes their separation. 

The reversal of the direction of the electro-osmotic flow by the adsorption onto the capillary wall of alky-lammonium surfactants and polymeric ion-pair agents incorporated into the electrolyte solution is widely employed in capillary zone electrophoresis (CZE) of organic acids, amino acids, and metal ions. The dependence of the electro-osmotic mobility on the concentration of these additives has been interpreted on the basis of the model proposed by Fuerstenau [6] to explain the adsorption of alkylammonium salts on quartz. According to this model, the adsorption in the Stern layer as individual ions of surfactant molecules in dilute solution results from the electrostatic attraction between the head groups of the surfactant and the ionized silanol groups at the surface of the capillary wall. As the concentration of the surfactant in the solution is increased, the concentration of the adsorbed alkylammonium ions increases too and reaches a critical concentration at which the van der Waals attraction forces between the hydrocarbon chains of adsorbed and free-surfactant molecules in solution cause their association into hemimicelles (i.e., pairs of surfactant molecules with one cationic group directed toward the capillary wall and the other directed out into the solution). 

Free Solution-CE, FSCE, also called Capillary Zone Electrophoresis, CZE), molecular size (SDS-CGE in capillaries filled with an acrylamide gel), or isoelectric point (CIEF). 

One significant application of ADSEP electrophoresis is direct measurement of electrophoretic mobilities as demonstrated in the present work. Capillary zone electrophoresis (CZE) is normally used to measure the electrophoretic mobility of solutes in free solution. Several undesirable features of CZE are absent in the present version of ADSEP, namely ... 

The heptakis-(sulfobutyl)-pCD is very soluble in water. noncrystallizable. and even at extremely high doses seems to be free from any toxic side effects. It can be used as a chiral separating agent in capillary zone electrophoresis. But, the aim of intensive research is to develop it as a parenteral drug carrier, for preparation of aqueous injectable solutions of poorly soluble drugs. 

Using capillary zone electrophoresis (CZE), the free solution mobility of human insulin was measured to be 0.00027 cmV(V.Sec) at pH 2.5. Since this mobility is the highest mobility measured for any pH, it can be used as... 

Furthermore, Grossman and Soane [66] have studied the effect of molecular orientation on the electrophoretic mobility of a macro ion in free solution (the tobacco mosaic virus was a model) by using the capillary zone electrophoresis technique. 

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