A chromatographic device includes a primary channel having a cross-sectional area and characteristic length such that analyte travel within the primary channel is substantially convective. A plurality of secondary channels each having a cross-sectional area and characteristic length such that analyte flow into and out of a secondary channel is substantially diffusive, each of the plurality of secondary channels having an entrance in fluidic communication with the primary channel wherein the entrance intersects the primary channel.

A liquid chromatography (LC) column includes a wall having a length along a central axis from the inlet end to the outlet end, the wall enclosing a column interior and having a column radius relative to the central axis, the wall comprising a structured portion configured such that the column radius varies along the length; and a plurality of particles packed in the column interior, wherein at least some of the particles are in contact with the structured portion.

Disclosed is a separation column for micro gas chromatography, having superior separation performance and including a microchannel formed on a substrate and having a serpentine shape, and bumps formed on the surface of the microchannel, wherein the bumps are alternately disposed to face each other on the surface of the microchannel. In the separation column for micro gas chromatography, a sufficient pressure drop occurs, and thus an M interaction between a gas mixture to be analyzed and a stationary phase in the column sufficiently takes place, whereby individual gas components are efficiently separated from the gas mixture, discharged from the column, and detected.

An apparatus and a method are provided for column chromatography which provide improvements in separation resolution and detection sensitivity, comprising a chromatography column, the column having an inlet and an outlet, wherein the outlet is configured to split a flow of eluate as it leaves the column through the outlet into at least two separate portions, wherein the apparatus is configured to separately process the portions, for example to separately detect a portion or separately collect fractions of a portion with improved resolution. A split frit assembly is preferably configured to split the flow of eluate. The portions preferably emanate from different radial regions of the column. An end fitting for the column outlet may be provided having multiple ports to separately convey the portions.

An apparatus and a method are provided for column chromatography, which provide improvements in separation resolution and detection sensitivity, comprising a chromatography column having an inlet and an outlet, wherein the inlet is configured to introduce a flow of mobile phase into the column carrying a sample, wherein the inlet is further configured to introduce the flow of mobile phase into the column in at least two separate portions which are independently controllable, and to introduce the portions into different radial regions of the column, such that the portions flow longitudinally through the column in different radial regions. The sample preferably is contained in one of the portions, especially a central portion, in a higher concentration than in the other portion(s). Preferably the flow velocities of the portions are independently controllable.

A liquid chromatography (LC) column includes a wall having a length along a central axis from the inlet end to the outlet end, the wall enclosing a column interior and having a column radius relative to the central axis, the wall comprising a structured portion configured such that the column radius varies along the length; and a plurality of particles packed in the column interior, wherein at least some of the particles are in contact with the structured portion.

A method of forming a frame around a membrane stack for a laterally-fed membrane chromatography device is provided. The method includes placing a membrane stack having one or more membrane layers on a bottom surface of body of a master mold, the body having opposed side walls and opposed end walls, the opposed side walls spaced apart by a distance greater than a length of the membrane stack, the opposed end walls spaced apart by a distance greater than a width of the membrane stack; placing a cap on the body of the master mold to enclose the membrane stack in the master mold, the cap having at least one opening for injecting a material into a space defined by the end walls of the master mold, the side walls of the master mold, end walls of the membrane stack side walls of the membrane stack, the bottom surface of the body and an inner surface of the cap; injecting the material into the space around the membrane stack; and curing the material to form a frame around the membrane stack.

A wavy micro gas chromatography column includes a silicon substrate and a bonded glass cover. A micro channel having a rectangular cross section is etched on the silicon substrate and coated with a stationary phase film. A projection figure of the micro channel on the silicon substrate includes multiple regular wavy curves. Each wavy curve is formed through alternately connecting first upper arcs with first lower arcs. Because the groove has a curving structure, the carrier gas velocity is decreased as the increase of the arc angle, resulting in an improvement of the flow uniformity at the zones between two adjacent bends but also an enlarging nonsymmetric distribution at the bends. Thus, an optimal curving structure can make the overall flow more even, and in turn achieve a better separation performance compared to the straight channel columns. Meanwhile, a wavy channel realizes a longer column length on a given area.

A laterally-fed membrane chromatography device for removing a solute from a fluid is provided. The device has a top plate, a middle plate and a bottom plate. The top plate has an inlet and a top channel for directing the fluid from the inlet towards a membrane stack. The middle plate houses the membrane stack. The membrane stack has a leading edge for receiving the fluid from the top channel, a trailing edge for distributing the fluid to the bottom channel, and is configured to remove the solute from the fluid as the fluid passes through the membrane stack. The bottom plate has a bottom channel and an outlet. The bottom channel is for directing the fluid from the membrane stack to the outlet. The top channel directs the fluid form the inlet over the leading edge in a direction that is transverse to the direction of flow of the fluid through the membrane stack.