Abstract: Separation of sample ions on the basis of molecular size is achieved by electrophoresis in an aqueous solution containing a dissolved non-crosslinked polymer. The polymer has a molecular weight range which overlaps that of the sample ions being separated. Species which vary in molecular weight but not in charge/mass ratio are separated by this method, which is of particular interest in high performance electrophoresis in capillary columns where the use of gels would be awkward and inconvenient.

Abstract: Bulk fluid movement in a capillary column is achieved by creating electroendosmotic flow in a fluid passage outside the column, the fluid passage being joined to the column in a manner which causes the electroendosmotic flow to generate bulk flow in the column and yet permits an electric potential to be applied across the fluid passage and not the column. Small volume bulk fluid movement induced in this manner may be used to load sample into the column, whereas a larger induced volume may be used for flushing the column between runs. To alternate the bulk fluid movement with electrophoretic separations in the column, the column is arranged such that an electric potential can also be applied across the column without extending to the electroendosmotic fluid passage.

Abstract: Zones of ampholytic substances which have been isoelectrically focused in a separation medium are mobilized for analytical or preparative purposes by either introducing anions other than hydroxyl ions to the separation medium toward the catholyte end or adding cations other than protons to the separation medium toward the anolyte end to produce a pH shift in the separation medium, thus restoring a charge to the focused ampholytes so that they will mobilize under the influence of a voltage applied across the medium. In preferred embodiments, the anion or cation introduction is achieved by supplementing the catholyte or anolyte, respectfully, with a strong electrolyte and permitting the cations or anions to migrate into the separation medium under the influence of the electric field. Detection is achieved by permitting the focused zones to migrate past a fixed point in the separation medium.

Abstract: Bulk fluid movement in a capillary electrophoresis system is achieved by imposing a temperature change on either a portion of the capillary or a bulb joined to the capillary at one end. The process may be used for sample loading, in which case a small volume introduction is made, or for flushing of the capillary with buffer solution, in which a larger volume introduction is made. The temperature change may be either an increase or a decrease, and the volume passed into or through the capillary is controlled to a high degree of precision by selection and accurate measurement of the volume of the bulb or capillary portion to which the temperature change is applied together with accurate control of the temperature change itself.

Abstract: Protein zones which have been isoelectrically focused in a separation medium are mobilized for analytical or preparative purposes by changing the anolyte, catholyte or both to provide these two solutions with pH's varying in the same direction from the isoelectric points of each of said protein zones, then applying a voltage between them. The focused protein zones then elute as a unit from the separation medium while substantially maintaining their same positions relative to each other without hydrodynamic flow through the medium itself. Mobilization is alternatively achieved by hydrodynamic flow, for instance by pumping the focused protein zones with voltage maintained to suppress zone distortion (due to the hydrodynamic flow) and zone broadening (due to diffusion).

Abstract: Coated capillary tubes useful for performing free electrophoretic separation techniques are prepared by reacting the interior wall of the tube with a bifunctional compound having a first functional group capable of covalently attaching to the wall and a second functional group capable of being polymerized. After such covalent attachment, free monomer is reacted with the second functional group, resulting in the formation of a monomolecular polymeric layer covalently attached to the interior wall of the capillary tube. This polymeric layer inhibits electroendosmosis and adsorption of the substances to be separated onto the interior of the tube, providing for improved separation.

Abstract: The invention relates to a method for cross-linking of agar products in an alkaline surrounding. According to the invention divinylsulfone is used as cross-linking agent in a manner known per se. The cross-linking is performed at room temperature at pH>11 in the presence of a reducing agent, and unreacted vinyl groups are deactivated by means of a neutral hydrophilic deactivating substance comprising several hydroxyl groups. The cross-linking was stable even at a pH as high as 13 during a test period of 15 days.