Abstract: Volume flows of liquids in capillary tubes of chromatographic separation columns for analytical liquid measuring technology are controlled. The volume flows are derived from a liquid transport, i.e., pump arrangement, which transports a total flow to a flow splitter that divides the total flow into an excess flow in an excess path and a working flow in a working path. A controller for the working flow responds to at least one working sensor. The working sensor senses the mass flow rate of the working flow and/or the pressure in the working path which is coupled with the working sensor or the pressure differential in conduits for the excess and working flows.

Abstract: A laboratory microchip providing a microspray has a substrate having a channel structure on one side thereof. A microspray tip is on the other side of the substrate close to an edge of the substrate. The substrate is deformable in a particular region. Deformation results from thinning the substrate locally in the region or by providing a linear perforation that extends approximately perpendicular to the plane of the substrate. Alternatively, deformation can be obtained by selecting a suitable material for the entire substrate. Substrate deformation can be permanent or reversible.

Abstract: What is described in this case is a laboratory microchip having microspray means whose direction of spray can be altered. The microchip has a substrate 40 which has a channel structure provided on one side 41 thereof. On the other side (in the region of an edge of the substrate in the present case), there is a microspray tip 42. Substrate 40 is designed to be deformable particularly in a region 43, in which case the deformability may be achieved either by thinning the substrate material locally in this region 43 or by means of a linear perforation extending approximately perpendicularly to the plane of the paper. Alternatively, the deformability may be obtained by selecting a suitable material for the entire substrate. A microchip which has been bent in the manner indicated is shown in the bottom part of FIG. 3. The bending of the substrate which is shown has turned the direction of spray 44 of microspray tip 42 through 90°. The bending of the substrate may be permanent or reversible in this case.

Abstract: A laboratory microchip includes a carrier with a micro spray tip projecting vertically out of a plane of the carrier. The carrier and spray tip are designed as a monolithic or single unit. The spray tip includes a passage channel which conveys the substances to be sprayed from a channel to a spray tip aperture. The channel is a part of a channel structure which is enclosed to the outside by a cover plate. The spray tip includes, on the sides of the spray aperture, an area which tapers conically inwards. Connected to this tapered area is a constant cross-section drill hole forming an annular internal step formation at the transition between the two areas. The outer diameter of the conically tapering tip is locally reduced in proximity to the aperture to provide a finer tip to the spray tip. The finer tip increases the electrical fields occurring at the tip, to further increase the forces which act on the substances and for dispersion spraying.

Abstract: A column for capillary chromatographic separations, for example high performance liquid chromatography, capillary electrochromatography, or supercritical chromatography, includes a column bed of packing material arranged in the inner bore of the column, and a retainer for retaining the column bed in the interior of the column, wherein the retainer includes regions in the interior of the column having radial dimensions which are different from that of the inner bore. Preferably, the column is a fused silica capillary whose protective layer is removed in a detection area so that sample substances separated in the column can be detected by means of a light source which transmits radiation through the column which is detected by a detector.

Abstract: An apparatus for handling liquid vials in an analytical device comprises a single movable tray for accommodating a plurality of vials, and lifting devices arranged in the proximity of the tray for lifting vials out of the tray. The tray has a plurality of recesses for holding the vial. The recesses are open at the bottom so that a vertically movable finger of a lifting device which can be positioned underneath the bottom of a vial can move the vial out of the tray by an upward movement. When a vial has been lifted out of the tray, the tray remains freely rotatable so that a different vial can be positioned at a further lifting device and then lifted out of the tray. The invention provides a mechanically simple apparatus which is particularly suited for capillary electrophoresis for handling vials containing sample and electrolyte liquid.

Abstract: An apparatus for performing capillary electrophoresis comprises a housing (37) to which a sealing and electrode arrangement (36) is fastened and a removable cassette (22) which accommodates a capillary (1) in which electrophoretic separation of a sample takes place when an electric field is applied. When performing an electrophoretic separation, the end of the capillary (1) and a tube-shaped electrode (39) surrounding the capillary (1) dip into a liquid vial containing electrolyte or sample liquid. Liquid is injected into the capillary (1) by applying pressure on the liquid in the vial. An elastomeric seal (40) around the capillary (1) is provided to prevent escaping of the pressure during injection. The end of the capillary (1) depending from the cassette (20) is introduced through a funnel (41) and a central bore in the seal (40). When the cassette (20) is pressed downwards onto the funnel (41), the elastomeric seal (40) is squeezed so that the capillary (1) is sealed off.

Abstract: Apparatus and methods for processing liquids are provided. The apparatus include open-ended, hollow reactor compartments which are detachably connected to receptor ends of tube systems. In preferred embodiments, a portion of the tube system is fixed to a rotor arm which can be rotated in a circle and moved up and down. Another portion of the tube system is coupled to a metering syringe which serves for drawing in or ejecting fluids into or from the reactor compartment and/or the tube system. A plurality of process stations such as bottles containing reagents or solvents can be arranged on a circular tray such that they can be accessed by the reactor compartment or by the receptor end if the reactor compartment has been detached from the tube system. The invention can be used, for example, for automatic protein sequencing, whereby the proteins to be sequenced are held in place by a matrix in the reactor compartment.