Other

Vladislav Dolnik

Marcella Chiari

William A Gurske

Disclosed herein is a device for separation and analysis of trace and ultra-trace ionogenic compounds by isotachophoresis-zone electrophoresis on a chip with online detection and method of its use, concentrating trace and ultra-trace analytes by isotachophoretic migration in a wide separation channel when a manifold of auxiliary electrodes is employed. Then the isotachophoretic zones of trace and ultra-trace analytes are transferred by isotachophoretic migration through a tapered channel, while corresponding auxiliary electrodes are progressively disconnected from the power supply. When the isotachophoretic zones enter the analytical capillary channel, the mode switches to zone electrophoresis and an online detector detects analytes for qualitative and quantitative analysis.

Device and method for separation and analysis of trace and ultra-trace ionogenic compounds by isotachophoresis and zone electrophoresis on chip

Disclosed herein is a composition of a separation medium and method of its use for electrophoresis in bare channels, either capillaries or chips, with suppressed electroosmotic flow, wherein various forms of boric acid are adsorbed on the wall of said separation channel, efficiently suppressing zeta potential of the wall of said bare channel. A composition of a sieving separation medium for electrophoresis of DNA is disclosed. A composition of a sieving separation medium for electrophoretic size separation of proteins by SDS CSE is also disclosed. A composition of a separation medium for capillary electrophoresis without sieving is also disclosed.

Separation medium for capillary electrophoresis suppressing electroosmotic flow in bare capillaries and channels

Disclosed herein is a composition and method for sample preparation of proteins for their size separation by electrophoresis, suitable for molecular-weight determination of proteins in the range between about 14,000 and 500,000. In an embodiment, proteins, particularly those exhibiting biased migration, are modified to change their intrinsic charge, or carbohydrate component to improve accuracy of their molecular weights as determined by electrophoretic size separation via their interaction with ionic surfactants. In a preferred embodiment, the proteins are carbamylated with potassium cyanate and their carbohydrate components are oxidized with sodium periodate.

Chemical modification of proteins for their more accurate molecular-weight determination by electrophoresis

The present invention describes a method of preparation of a permanent neutral wall coating made of thermally immobilized polysaccharides. The coating suppresses electroosmotic flow and adsorption on the wall under acidic, neutral, and basic conditions in capillary electrophoresis.

Neutral polysaccharide wall coating for electrophoretic separations in capillaries and microchannels

The present invention describes a method and apparatus utilizing a capillary coating of linear and crosslinked polymers and copolymers of acrylamidomonomers or methacrylamides bearing two hydroxyethyl residues. The method and apparatus employ this coating to maintain coating integrity and suppress electroosmotic flow under basic conditions in capillary electrophoresis.

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Palo Alto, CA, United States of America

Vladislav Dolnik