Abstract: A flow meter with a metering device for intaking and metering a defined volume of a fluid, and with a control unit for controlling the fluid intake of the metering device for determining a flow rate of the fluid.

Abstract: A voltage control circuitry for a detection cell (1) is described, whereby the detection cell (1) is adapted for determining an electrical property of a sample in a detection cell volume (2) of the detection cell (1). The voltage control circuitry comprises a power supply (5) adapted for providing a voltage (6) to the detection cell (1), and a power evaluation unit adapted for determining an actual power dissipation in the detection cell volume (12). The voltage control circuitry further comprises a control unit (14) adapted for comparing the actual power dissipation with a desired power dissipation, and for regulating the power supply's voltage (6) in a way that the actual power dissipation is driven towards the desired power dissipation.

Abstract: A microfluidic system, particularly a microfluidic chip, with at least one operational channel, in which a fluid and/or the constituents contained therein are moveable in the direction of the operational channel by a driving force, particularly by using pressure, acoustic energy, or an electrical and/or a magnetic field. At least one measurement sensor used to measure a measurable value assigned to the fluid and derivable in the region of the fluid and at least one regulator is provided to regulate the driving force and/or a parameter that may be influenced by it, wherein the regulator is coupled with a measurement sensor and a device used to alter the driving force and/or the parameter that may be influenced by it. The microfluidic system further relates to a procedure to transport and guide a fluid and/or the constituents contained therein within a microfluidic system of the type described above.

Abstract: A detection cell for detecting at least one sample compound of a sample is described. The detection cell includes an activation facility adapted for inducing at least one of a physical and a chemical modification of at least one sample compound, in order to generate one or more derived species. The detection cell further includes a detection facility adapted for detecting a detectable property that is directly or indirectly affected by the presence of at least one of the derived species.

Abstract: An apparatus for analyzing a mixture of sample substances comprises a fluid-guiding structure wherein the sample substances are moving essentially in one dimension along the structure and are subject to at least two separation mechanisms, such as capillary electrochromatography (CEC) and capillary zone electrophoresis using high voltage. The signals from a detection means are supplied to a signal processing means, which derives a parameter therefrom which in turn is used to derive improved measuring results for each of the separation results associated with the various separation mechanisms, respectively. The apparatus can be used for protein analysis, for example in combination with a mass spectrometer.

Abstract: A supply flow path for supplying a solvent is described. The supply flow path comprises a metering device with a piston, the metering device being adapted for metering the solvent. The supply flow path further comprises a control unit adapted for controlling the metering device's piston movement in accordance with solvent pressure, wherein a variation of the solvent pressure gives rise to a corresponding variation of a solvent volume contained in the supply flow path or a part thereof. The control unit is adapted for compensating for the variation of the solvent volume by a corresponding corrective movement of the piston.

Abstract: An apparatus for analyzing a mixture of sample substances comprises a fluid-guiding structure wherein the sample substances are moving essentially in one dimension along the structure and are subject to at least two separation mechanisms, such as capillary electrochromatography (CEC) and capillary zone electrophoresis using high voltage. The signals from a detection means are supplied to a signal processing means, which derives a parameter therefrom which in turn is used to derive improved measuring results for each of the separation results associated with the various separation mechanisms, respectively. The apparatus can be used for protein analysis, for example in combination with a mass spectrometer.

Abstract: The invention relates to a microfluidic system (110), particularly a microfluidic chip, with at least one operational channel (170), in which a fluid and/or the constituents contained therein are moveable in the direction of the operational channel (170) by a driving force, particularly by using pressure, acoustic energy, or an electrical and/or a magnetic field. At least one measurement sensor (185) used to measure a measurable value assigned to the fluid and derivable in the region of the fluid and at least one regulator (192) is provided to regulate the driving force and/or a parameter that may be influenced by it, wherein the regulator (192) is coupled with a measurement sensor (185) and a device used to alter the driving force (189) and/or the parameter that may be influenced by it. The invention further relates to a procedure to transport and guide a fluid and/or the constituents contained therein within a microfluidic system of the type described above.

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: In a method and a corresponding apparatus for injecting liquid from a vial into a capillary tube, in particular in capillary electrophoresis, a source of overpressure and a source of underpressure are connectable to the vial for applying overpressure or underpressure in the space above the liquid. During an injection, the pressure is continuously varied in a controlled way by corresponding control of the pressure sources, for example by controlling associated valves. The pressure is first gradually increased and then gradually decreased. The actual pressure variation during an injection is measured by a pressure sensor and used by a controller to control the durations of the time intervals during which overpressure or underpressure are applied such that a desired amount of liquid is introduced into the capillary.

Abstract: Apparatus for controlling the temperature of a mobile phase in a fluid chromatographic system are provided which comprise both an ingoing capillary connected to an inlet of a column and an outgoing capillary connected an outlet of the column. A portion of the ingoing capillary and a portion of the outgoing capillary are arranged in thermal contact with each other to form a contact region wherein heat exchange can occur. In preferred embodiments, liquid leaving the column at an elevated temperature loses a portion of its heat, thus avoiding or at least substantially reducing the transfer of heat to the detector. At the same time, liquid flowing to the column is pre-heated by the liquid leaving the column so that the heating power required for bringing the mobile phase to the desired temperature is reduced as compared with prior art devices.

Abstract: A pumping apparatus for delivering liquid at a high pressure, in particular for use in liquid chromatography, comprises two pistons (10, 20) which reciprocate in pump chambers (7,18), respectively. The output of the first pump chamber (7) is connected via a valve (13) to the input of the second pump chamber (18). The pistons are driven by linear drives (30,31), e.g., ball-screw spindles. The stroke volume displaced by the piston (10) is freely adjustable by corresponding control of the angle by which the shaft of the drive motor (36) is rotated during a stroke cycle. The control circuitry is operative to reduce the stroke volume when the flow rate which can be selected by user at the user interface (42) is reduced, thus leading to reduced pulsations in the outflow of the pumping apparatus. The pumping apparatus can also be used for generating solvent gradients when a mixing valve (2) connected to different solvent containers (A,B,C,D) is coupled to the input of the pumping apparatus (FIG. 1).