Abstract: A pinch valve for selectively pinching or releasing a multiple plurality of fluid conduits includes a rotatable single cam as part of a rotor within a stator for locating the fluid conduits. The cam periphery with different lobe surfaces for engaging movable means which is either a plunger or a endless belt which pinch or release multiple fluid conduits. The rotor integrally includes a gear, shaft and flag indicator and is operable by a stepper motor. A backing means about the stator resiliently resists movement.

Abstract: An indirect potentiometric method and diluent for the analysis of lithium are disclosed. The diluent includes effective amounts of a pH buffer, at least one lithium salt, and a non-cationic surfactant containing at least one hydrophobic group, at least one hydrophillic group and being substantially free of polyoxyethylene groups. Most preferably, the pH buffer is tris-(hydroxymethyl)aminomethane-phosphate, the lithium salt is lithium chloride, and the surfactant is 2,4,7,9-tetramethyl-5-decyn-4,7 diol.

Abstract: An automated multi-purpose analytical chemistry processing center and laboratory work station having a movable table for supporting microtiter plates and other fluid receptacles, a movable arm, and a modular mobile pod affixed for reciprocal movement along the arm. The work station combines into a single programmable system the capabilities for automation of a wide range of bioanalytical procedures including, not only sample pipetting, serial dilution, reagent additions, mixing, reaction timing and similar known manual procedures, but also programmable spectrophotometric measurements and other physical parameters, further processing based on these measurements and automatic data recording. The work station is adapted to transfer, dispense, and aspirate liquid from one location to another automatically in accordance with user programmed instructions.

Abstract: An automated multi-purpose analytical chemistry processing center and laboratory work station having a movable table for supporting microtiter plates and other fluid receptacles, a movable arm, and a modular mobile pod affixed for reciprocal movement along the arm. The workstation combines into a single programmable system the capabilities for automation of a wide range of bioanalytical procedures including, not only sample pipetting, serial dilution, reagent additions, mixing, reaction timing and similar known manual procedures, but also programmable spectrophotometric measurements and other physical parameters, further processing based on these measurements and automatic data recording. The work station is adapted to transfer, dispense, and aspirate liquid from one location to another automatically in accordance with user programmed instructions.

Abstract: A method and specimen slide for obtaining fecal occult blood specimens. The slide includes first and second portions each including front and back panels. The first portion includes one or more apertures formed through its front panel which exposes a reagent-carrying sheet and the back panel of the first portion includes a flap that may be opened for the application of additional reagents to the back of the sheet. The second portion includes an aperture in its front panel and a flap formed in its back panel. A sheet is carried between the front and back panels of the second portion onto which a fecal specimen may be smeared. The sheet includes pre-perforated removable portions that may be easily accessed through the flap. As an alternative embodiment, the back panel of the second portion may include a removable tab to which is fixed the specimen sheet. The tab and specimen sheet may be removed for easy access to the removable portions of the specimen sheet.

Abstract: A method and apparatus for improving signal to noise in an electropherogram acquired by electrophoresis. The migration time is remapped by binning the data with respect to migration time to improve signal to noise and peak resolution. The data points of the electropherogram are pooled into variable size bins, each corresponding to a number of time intervals. The sizes of the bins increase with migration time. To further improve signal to noise and peak resolution, the binned data is filtered by Fourier transformation. The present invention allows for accurate determinatiion of DNA sequences.

Abstract: Disclosed is a gel-containing capillary column useful in high performance capillary electrophoresis. A preferred column includes a microcapillary having an interior cavity and a wall with an inner surface; a bifunctional agent comprising a positively charged amine adsorbed to the inner surface of the wall and an active functional group capable of copolymerizing with a polymeric gel material; and a polymer gel material filling the interior cavity of the microcapillary.

Abstract: A scatter signal is produced from light scattered by a precipitate formed by a chemical reaction and non-specific scatter sources. A blanking signal is produced from light scattered only by the non-specific scatter sources that contribute to the scatter signal, and the blanking signal is subtracted from the scatter signal to dynamically produce a signal indicative of the difference between the scatter signals to reduce the effects of non-specific scattering sources in determining the rate of change of the light scattered by the precipitate. One of the scatter signals may be stored and then combined with the other, or the signals may be measured simultaneously and then combined.

Abstract: A robot gripper module having a housing pivotally mountable to an end of a robot arm. The housing encloses a first motor for pivoting the housing about a pivot joint, and a second motor operating a rack-and-pinion gear arrangement for extending and retracting fingers. Two opposed groups attached to a rack on opposite sides of a pinion gear. Turning the pinion gear causes the fingers to move toward or away from one another. The motors which may operate independently of the robot arm, may be either servo or stepper motors. The gripper module provides additional degrees of freedom from that of the robot arm, enabling it to work with many kinds of robot arms.

Abstract: A electrophoretic system in which nonconductive members are strategically positioned in the electrolyte tank to selectively affect the electric field of electrodes so as to obtain a desired electric field for efficient separation. The size, shape and location of the nonconductive members are selected using a electric potential analysis.

Abstract: A reagent cartridge for use in an automated clinical analyzer, the reagent cartridge including a plurality of storage compartments each including wall members. The reagent cartridge includes connecting members formed integrally with the storage compartments for holding the storage compartments in a fixed relationship with respect to each other and separating the wall members from each other to thus prevent reagent migration between adjacent reagent compartments. Each of the storage compartments includes an access opening and a neck formed about the opening, the neck including a collar that is spaced a predetermined distance from a bottom wall of the associated storage compartment, the predetermined distance adapted to accommodate an automatically controlled reagent transfer probe.

Abstract: A rotatable turntable for vortexing reactants comprises a vortexing plate which is rotatable. The motor drives for vortexing and rotation are stationary such that simple mechanical and electrical connection relative to the peripheral supports and to the vortexing plate can be achieved. A vortexing work station located in alignment with the turntable operates in synchronism with the turntable. Reactants at any radial reactant station on the vortexing plate can be withdrawn from and located onto the turntable at any radial location when the turntable stops rotation. The radial position of the turntable in relation to the outside vortexing and non-vortexing periphery remains relatively aligned.

Abstract: A hybrid centrifuge rotor having a rotor core surrounded by a prestressed anisotropic reinforcement ring is disclosed. The rotor core may be made from aluminum and an anisotropic reinforcement ring may be a cylindrical filament wound ring, made from graphite fiber and epoxy resin. The rotor core is manufactured to have a nominally greater diameter than the inner diameter of the reinforcement ring. This rotor core, during the manufacturing process, is subjected to a cryogenic environment where the diameter is shrunk down so that the rotor body may fit and telescope within the reinforcement ring. The rotor body core and reinforcement ring assembly, upon attainment of ambient temperatures, have an interface fit wherein substantial outward force from the rotor body core prestresses the reinforcement ring so that a light weight and strong centrifuge rotor is disclosed.

Abstract: A reagent storage and delivery apparatus comprises a reagent cartridge having a plurality of fluidic chambers and includes a flange means for receiving a label to define a code indicating information concerning the contents of the cartridge. Preferably, a binary code is defined through use of windows formed in an extending portion of the cartridge which cooperate with a formed portion of the label applied to the cartridge. The binary code is optically read and translated to a digital information signal for instructional use with an analytical instrument.

Abstract: Determining whether a liquid scintillation sample is single- or multi-phase includes transforming all or a portion of a Compton Spectrum of data into different namely integrated, geometric space. A predetermined parameter in the selected geometric space, indicative of the phase content of the sample is selected, and compared with the data in the different geometric space. This provides a determination of the phase content of the sample. The linearity of the data indicates the phase content.

Abstract: A centrifuge rotor and method for gradient density separation which supports a generally cylindrical volume of sample solution with its axis inclined to the spin axis at an angle which is optimized for maximum separation efficiency while reducing contamination by undesirable centrifugates upon reorientation of the desirable centrifugates. The optimum angle is determined based on the relationship .theta.=Tan.sup.-1 (D/15L).sup.0.5 where D and L are respectively the diameter and length of the cylindrical volume of the sample solution and .theta. is the angle of inclination.

Abstract: An automated chemical conversion unit for use in a peptide/protein sequencing process. The improved conversion methodology decreases the time necessary for the conversion reaction chemistry of the specific derivative of the sequenced amino acid to a more stable form. The conversion reaction is designed to be performed directly in a fraction collector tube which operates in one embodiment in conjunction with a thermoelectric temperature element to allow utilization of different temperature levels for different amino acid derivatives.

Abstract: A monobeam system for determining concentration changes of chromophore substance in a sample includes a flash lamp for passing a light beam through a sample containing the analyte. The values of absorbance by the sample at multiple wavelengths are measured and the optimum linear combination of absorbance values is determined to obtain a measure of chromophore concentration. Extinction coefficients for a chromophore is measured employing Deming's method and eigenvector transformations. A matrix reflecting the noise pattern of the system is determined. This matrix and the extinction coefficients are used in determining the coefficients for the optimum linear combination. An electronic module converts analog intensity data into digital data for five wavelengths. This is processed into absorbance values and concentration determinations.

Abstract: Solid phases such as capillary tubes or solid supports used in chromatography, and in particular electrophoresis, are treated with oxidizing or reducing agents as needed to maintain or restore surface electrical charges or the lack thereof, which become modified during electrophoresis as a result of action by system components in the separation medium or the solutes themselves. The treatment is used as a means of achieving reproducible electroosmotic bulk flow when desired or suppressing unwanted electroosmotic flow arising due to the accumulation of charges on the surface. The result is improved reproducibility of retention times and component separation.

Abstract: A stable reagent and kinetic assay for .alpha.-amylase is provided. The reagent comprises a substrate for the .alpha.-amylase and various enzymes and cofactors necessary to produce NADH as the end-product of a series of four reactions. The substrate, enzymes, and cofactors are provided in sufficient excess that the .alpha.-amylase from the test sample is the rate-limiting factor. The concentration of .alpha.-amylase in a test sample is determined by measuring the rate of increase in absorbance caused by the production of NADH. The use of the novel cofactor fructose-1,6-diphosphate has been found to impart improved stability to the reagent.