Abstract: To detect bands in an electrophoresis capillary tube having a liquid separating medium, a light source and a light detector of a monitor are positioned on opposite sides of the capillary tube with the light source transmitting light through a first slit and light passing to the detector through a second slit after it has passed through the capillary tube. The first and second slits are aligned with the direction of motion of bands, have a maximum length of less than 500 micrometers and a maximum width of less than 200 micrometers. There are no vertical lengths in the capillary tube having a dimension greater than one third of its length between a sample injecting end and a detecting end of the capillary tube.

Abstract: A present invention and method provides a pressure injection apparatus (20) that injects a quantitatively defined volume of liquid sample (21) from a container (22) into a capillary device (23). A servo pressure primary regulator (26) is included which precisely regulates the fluid from a supply pressure (P.sub.S) to a substantially constant regulated pressure (P.sub.R) in communication with the liquid sample (21) for a predetermined period of time. A feedback mechanism cooperates with a valving assembly (31) to continuously monitor and adjust the regulated pressure (P.sub.R) to be substantially constant and precise for delivery to the container (21).

Abstract: A gel pump operated by a stepper motor may be used to deliver fresh gel to one or more capillaries through one or more manifolds and valves. By controlling the valves, fresh gel delivered by the pump will replace the old gel in the capillaries for an automated gel replacement system. In a different setting of the valves, the manifolds may be purged of the old gel prior to delivery of fresh gel to the capillaries. The gel delivery system may also be combined with an electrophoresis system so that sealing connection capable of withstanding high pressure adequate for gel injection need not be frequently broken when the gel is to be replaced. Manifold/reflector assembly is advantageously used in the system that facilitates electrical circuit for electrophoresis and for gel replacement.

Abstract: Compositions, methods, and apparatus for performing ultrafast binding assays by capillary electrophoresis or other electroseparation techniques are disclosed. In one embodiment, a first binding partner carries a detectable label and a second binding partner is modified to be highly charged. When used in combination with a sample containing an analyte with which both binding partners can interact and bind thereto, a three-membered complex is formed. The electrophoretic mobility difference between the unbound and complex-bound forms of labeled first binding partner is such that electroseparation and subsequent detection of an analyte can be accomplished. The compositions, methods, and apparatus disclosed herein also permit quantitative determination of the concentration of an analyte in a sample.

Abstract: To detect bands in an electrophoresis capillary tube having a liquid separating medium, a light source and a light detector of a monitor are positioned on opposite sides of the capillary tube with the light source transmitting light through a first slit and light passing to the detector through a second slit after it has passed through the capillary tube. The first and second slits are aligned with the direction of motion of bands, have a maximum length of less than 500 micrometers and a maximum width of less than 200 micrometers. There are no vertical lengths in the capillary tube having a dimension greater than one third of its length between a sample injecting end and a detecting end of the capillary tube.

Abstract: A capillary and capillary retaining system including a capillary assembly having first and second end holders. The first and second end holders are adapted to be received by first and second retainers. The first end holder may include protruding portions and the first end retainer includes clips or clamps to engage the protruding portions. The second end holder may include opposite recesses and the second retainer is adapted to receive optical cables that are received within the recesses to retain the second end holder. The second retainer can further include a lever on the retainer body to pry the second holder out of the second retainer. Locks or clips retained by the second end retainer cooperate with grooves in the optical cables to retain the optical cables.

Abstract: An apparatus is disclosed for providing capillary electrophoresis, which includes an electronically controlled valve system for automatically introducing a sample into the capillary by means of a vacuum at the end of the capillary tube. This approach of sucking in the sample is extremely accurate and reproducible, and results in a minimum of band broadening. Furthermore, it enables the entire capillary electrophoresis sytem to be easily automated. An automated temperature control system is provided which enables the temperature of the capillary tube (and hence the solvent/solute system) to be controlled during electrophoresis, thereby very directly controlling pH and electrophoretic mobility. In another embodiment, the capillary is prewashed and equilibrated to achieve substantially zero charge on the capillary wall, thereby essentially eliminating electroosmotic flow and substantially improving resolution.

Abstract: A Capillary Electrophoresis apparatus and method are disclosed which utilize a meltable plug in an end of the capillary tube to selectively pass small ionic contaminants electrophoretically and retain macromolecular analytes against one end of the plug until the plug is melted. When this plug is melted, the analytes and the contaminants pass through unimpeded. This permits separation of the analytes from the contaminants during electrophoretic separation and enhances instrument resolution.

Abstract: A flow gating interface system including a first microcolumnar section, a second microcolumnar section, and a channel for interfacing a first fluid conduit and a second fluid conduit is provided. The channel, having an inwardly facing wall, encloses at least a portion each of the first microcolumnar section and the second microcolumnar section for conducting a flush fluid flow past the outlet end of the first microcolumnar section and the inlet end of the second microcolumnar section. The inwardly facing wall of the channel nonfixedly constrains and aligns the end portions of the first and second microcolumnar sections. The outlet end of the first fluid conduit is connected to and in fluid communication with the first microcolumnar section of the flow gating interface. The inlet end of the second fluid conduit is connected to and in fluid communication with the second microcolumnar section of the flow gating interface.

Abstract: An ionic liquid-channel charge-coupled device that separates ions in a liquid sample according to ion mobility characteristics includes a channel having an inner wall that has a matrix liquid disposed within. An insulating material surrounds the channel, and an introduction element introduces a liquid sample into the channel. The sample is preferably a liquid solution that has at least one ionic specie present in the solution. The device further includes a gating element that establishes at least one charge packet in the channel in response to an externally applied input signal, and a transport element that induces the charge packet to migrate through the channel. The gate element can be a plurality of spaced-apart, electrically conductive, gate structures that are alternately disposable between a high voltage state and a low voltage state. The transport element further includes an application element that applies a variable voltage to the gating element.

Abstract: A capillary electrophoresis method and apparatus for reducing dispersion of sample fractions are disclosed. The capillary tube in which the electrophoresis is performed has been flared, at least at its sample entrance end, to remove sharp corners which contribute to aberrations in the electric field distribution in a radial direction and result in differential migration of molecules depending on their proximity to the sharp corners. The flared tube, in contrast to a conventional tube, provides a more uniform electric field for electrophoresis and reduces undesired dispersion of the samples.