Hewlett-Packard Company

Agilent Technologies, Inc.

Robert R Holloway

Douglass McManigill

Darlene J Spira-Solomon

Hongfeng Yin

Ganapati R Mauze

Teddy T Kiang

Catherine A Keely-Templin

Ganapati R Nauze

Catherine A Keely

The present invention relates to capillary columns including a monolith and a method for preparing a capillary column including a monolith. The monolith can be prepared by a sol gel method, and in the transformation from hydrosol to hydrogel, the monolith undergoes essentially no syneresis or volume shrinkage. Thus, deleterious effects of syneresis are avoided, such as the formation of channels having large dimensions that provide a pathway of least resistance for a mobile phase to effectively bypass portions of a stationary phase. The method for preparing a column having a monolith that undergoes essentially no syneresis involves a hydrogel solution that has a relatively low concentration of SiO,, i.e. less than about 5 g/100 mL.

Monolithic silica column

A wide-bore capillary electrophoresis apparatus for the analysis of analyte ions is provided. The apparatus has a wide-bore capillary that has a restriction zone at one or more ends. The capillary has an inlet end and an outlet end and an opening at each of said ends. The restriction zone is capable of providing fluid communication between the wide bore and the opening at said end. The restriction zone includes a narrow bore extending to the opening and a transition zone providing gradual change of bore diameter from the wide bore to the narrow bore. The apparatus further has a buffer source to supply buffer to the inlet end of the capillary and a power supply for supplying power to drive buffer and analyte ions through the capillary. During CE, electrodes provide electrical communication between the power supply and the inlet end and the outlet end and apply a voltage differential between said ends.

Preparative capillary electrophoresis with wide-bore capillary

A system for controlling the bulk flow rate in capillary electrophoresis employs pressure to increase velocity without unacceptably increasing plate height. Thus, the system controls bulk flow over a range of velocities, independent of the chemistry of the system. Additionally, the use of pressure under certain conditions may decrease plate height and improve resolution.

Capillary electrophoresis flow control system

A method and apparatus for controlling the velocity of electroosmotic flow (EOF) in high performance capillary electrophoresis (HPCE) are provided. The interior surface of the capillary tube is coated with a zwitterionic coating, such that the pH range within which EOF velocity may be controlled is broadened. The zwitterionic coating involves covalent, ionic or adsorptive binding of a zwitterionic species such as phosphoryl choline to the capillary wall.

Capillary electrophoresis using zwitterion-coated capillary tubes

A dimensionally-stable organosilicon material composition and method for producing the material composition including non-crosslinkable, continuous phase silicone with silica filler material dispersed therethrough, and having dissolved therein a variably-radiative material (e.g., ruthenium dye) responsive to the concentration of a selected analyte (e.g., oxygen), and the products of a reaction between water and a modifier material selected for establishing the sensitivity of said variably-radiative material to the selected analyte.

Chemically sensitive, dimensionally-stable organosilicon material

Capillary tubes useful for performing capillary gel electrophoresis separation techniques are prepared by employing prepolymers having one or more terminal functional groups that allow for final polymerization. Use of said prepolymers significantly reduces the amount of shrinkage upon polymerization of said prepolymers to form the electrophoretic gel. The analytical media exhibits strong structural integrity, uniformity, and adheres well to the capillary tubes.

Capillary gel electrophoresis columns and method of preparing the same

A polyacrylamide gel electrophoresis column includes a fused-silica tube, a polyacrylamide gel matrix and a polydimethysiloxane layer radially between and covalently attached to both the tube and the gel matrix. The method for forming this column involves covalently binding polyorganosiloxane to the inner wall of the tube, covalently attaching organosilane termini to the organosiloxane layer, and polymerizing acrylamide so as to incorporate the organosilane termini into the resulting polyacrylamide gel matrix. Buffer ions are then drawn into the column under an electric field of about 1000 volts per centimeter, and, at the same time, different reaction product ions are removed. The polyorganosiloxane layer stretches as the polyacrylamide shrinks during polymerization so that the organosiloxane is at least twice as thick as it would be without the gel matrix attached. The process yields a gel matrix which is securely attached to the tube, void-free, and under minimal mechanical stress. As a result, the column can withstand relatively high-voltage pre-electrophoresis and electrophoresis procedures.

Capillary gel column with polyorganosiloxane coupling layer

Disclosed herein is a method of labeling room temperature vulcanizable silicon polymers at the 'T' junction branch points by utilizing cross-linkers of the formula D-SiX.sub.3, wherein X is a leaving group and D is a complex organic molecule useful as a dye, fluorophore, or indicator.

Covalently labeled siloxane polymers

A dimensionally-stable organosilicon material composition and method for producing the material composition including noncrosslinkable, continuous phase silicone with silica filler material dispersed therethorugh, and having dissolved therein a variably-radiative material (e.g., ruthenium dye) responsive to the concentration of a selected analyte (e.g., oxygen), and the products of a reaction between water and a modifier material selected for establishing the sensitivity of said variably-radiative material to the selected analyte.

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Montara, CA, United States of America

Robert R Holloway