Abstract: A method of positively deciphering a DNA sequence of a sample by comparing data of two electropherograms obtained from separate electrophoresis of products from two complete sequence reactions of the same sample, whereby dideoxynucleotide terminators of different but matched concentration ratios are employed for the two reactions. The sequencing chemistry is chosen to result in terminator-concentration dependent in peak intensity in the electropherograms. By appropriately choosing the matched concentration ratios of the terminators used in the two sequence reactions, ambiguities in the discrimination of the peaks in the result of one sequence reaction can be resolved by comparing the result of the other sequence reaction. The sequence of the sample can therefore be deciphered to a high degree of accuracy. For fluorescence detection of electrophoresis of the sequence reactions, three ddNTP terminators and one fluor are included in the sequencing chemistry of each reaction.

Abstract: A method for the generation of phenylthiocarbamyl (PTC) amino acids from phenylthiohydantoin (PTH) or anilinothiozolinone (ATZ) amino acids. The method involves a base-catalyzed ring opening of the PTH or ATZ in the presence of a reducing agent. The method affords an alternative to the established aqueous acid conversion reaction of the Edman degradation in which ATZ and PTC amino acids are converted to the PTH amino acid. A further method is described for the generation of reactive ATZ amino acids from PTH amino acids. These methods facilitate the analysis of protein at low molar amounts by allowing the synthesis of amino acid derivatives which can be analyzed in quantities which are much lower than those required for conventional PTH amino acid analysis.

Abstract: Disclosed herein is a methodology for analyzing isoenzymes using capillary zone electrophoresis ("CZE") techniques. Briefly, an isoenzyme-containing sample and a substrate capable of being catalyzed by said isoenzyme into a reaction product are introduced into a capillary column comprising a buffer. Most preferably, the buffer contains the substrate prior to introduction of the sample into such substrate-buffer. CZE separation techniques are applied to the column such that the isoenzymes are separated from each other into discrete zones. The separation techniques are terminated such that product is rapidly generated by the catalytic conversion of substrate by the isoenzymes, and accumulated, within each discrete zone, followed by detection of product. Information regarding the relative distribution of the isoenzymes can be derived from the relative distribution of the product.

Abstract: Disclosed herein is a dynamic coating buffer useful in the analysis of samples by open-tube capillary electrtophoretic methods using untreated fused silica capillary columns. The dynamic coating buffer comprises at least one agent having at least two dissociation constants, and high ionic strength characteristics, said agent having a molarity range of from about 0.2M and about 1.0M and a pH range of from between about 3.0 and 11.0. A particularly preferred dynamic coating buffer comprises 0.5M sodium phosphate.

Abstract: An improved fluid mixing device comprising a mixing chamber having end walls and a cylindrical side wall. A first fluid conduit joins the mixing chamber at a first port formed in the first end. A second fluid conduit joins the mixing chamber at a second port formed in the side wall. A second fluid conduit is angled with respect to the mixing chamber to direct fluid flow from the conduit through the second port generally along the wall of the mixing chamber to create a rapid vortexing action. A third conduit joins the mixing chamber at a third port in the second end. A fourth conduit intersects the third conduit, the center lines of the third and fourth conduits offset at the area of intersection.

Abstract: Disclosed herein are methodologies for the Capillary Electrophoretic Immunosubtraction ("CEI") of samples. In a preferred embodiment, CEI of a sample comprising constituent parts to be separated comprises the steps of: (1) separating a first aliquot of the sample into constituent parts by capillary electrophoretic techniques, and detecting said parts; (2) admixing a second aliquot of said sample with at least one specific binding partner to a constituent of said sample, said specific binding partner capable of being substantially removed from said aliquot; (3) separating said second aliquot into constituent parts by capillary electrophoretic techniques and detecting said parts; and (4) comparing the separated constituent parts of step (3) with the separated constituent parts of step (1).

Abstract: In a method for reducing the latent low-level phosphorescence of laboratory glassware, the glassware is illuminated by infrared light with a wavelength of about 780 nanometers. A suitable infrared light source can be a xenon flash apparatus fitted with an infrared light filter. A single flash from the xenon apparatus can substantially reduce the latent low-level phosphorescence of laboratory glassware to a baseline phosphorescence level.

Abstract: An automatic chemistry analyzer includes a flow cell mounted so that flow through the cell and tubing connected to the cell is visible from the front of the housing. The electrolytes to the cell are removably plugged into the cell from their rear. The probe aspirating sample fluid into an injection cell is simultaneously washed by diluent and the diluent mixes with the fluid sample. Waste fluid from the flow cell is fed to a basin which then feeds under gravity to a waste drain. A ratio pump is formed by selected syringes which are band driven to deliver accurately prerequisite volumes of reagents to the flow cell. The solution ground to the system is on the inlet line for sample adjacent the entrance to the flow cell of fluid thereby minimizing electronic noise. Only two motive means are necessary, one to effect horizontal and rotational movement of the sample tray, and a second to effect vertical motion of a crane mounted probe operative between sample cups and an injection cell.

Abstract: A centrifuge rotor overspeed protection system which can operate with rotors of at least two speed ranges. A set of coding elements are provided on the rotors coded to represent the actual maximum safe speed rating of the rotor. An additional set of coding elements coded to correspond to the maximum speed in the lower speed range are also provided such that the rotor can be operated at the maximum speed possible in a prior art centrifuge designed for operation in the lower speed range. The detection circuit for the coding elements automatically adjusts the detection threshold depending on the average values of the sensor output peaks corresponding to the codes.

Abstract: A two part peroxide/chromogen reagent for use in peroxidase labeled binding assays which is stable for at least about 24 hours is disclosed. The reagent is provided as two components, the first component preferably incorporating a peroxide dissolved in a first solvent, and the second component preferably having a chromogenic substance dissolved in a second solvent where the two components can be mixed within about 48 hours of colorimetric detection of an enzyme immunoassay.

Abstract: An automatic chemistry analyzer includes a flow cell mounted so that flow through the cell and tubing connected to the cell is visible from the front of the housing. The electrolytes to the cell are removably plugged into the cell from their rear. The probe aspirating sample fluid into an injection cell is simultaneously washed by diluent and the diluent mixes with the fluid sample. Waste fluid from the flow cell is fed to a basin which then feeds under gravity to a waste drain. A ratio pump is formed by selected syringes which are band driven to deliver accurately prerequisite volumes of reagents to the flow cell. The solution ground to the system is on the inlet line for sample adjacent the entrance to the flow cell of fluid thereby minimizing electronic noise. Only two motive means are necessary, one to effect horizontal and rotational movement of the sample tray, and a second to effect vertical motion of a crane mounted probe operative between sample cups and an injection cell.

Abstract: Disclosed herein is a capillary column containing a dynamically cross-linked composition and method of use. In a particularly preferred embodiment, the dynamically cross-linked composition comprises: 1.0% polyethylene oxide; 1.0% polyethylene glycol; 1.0% ethylene glycol; 100 mM TRIS-CHES buffer; and 0.1% sodium dodecyl sulphate, where the pH of the composition is between about 8.0 and about 9.0 and the viscosity of the composition is less than about 500 centipoise. The disclosed compositions can be used for the analysis of surfactant:proteinaceous material complexes and the generation of calibration curves over an extensive range of molecular weights, using capillary electrophoretic techniques. The disclosed compositions are particularly suited for capillary electrophoretic systems having UV-based detection.

Abstract: An apparatus xxx method of aligning a capillary with respect to a radiation source. More particularly, the capillary is aligned with a laser beam for laser induced fluorescence detection. The light reflection/scatter pattern of the laser beam originating from the capillary wall is utilized to determine optimum alignment. Photosensors may be implemented to detect the scatter pattern which represents optimum alignment. For dynamic alignment during electrophoresis, the photosensors provide feedback to a controller which controls a positioning mechanism for alignment of the capillary.

Abstract: A centrifuge rotor having a balancing ring integrally formed with and raised from the upper surface thereof is manufactured by removing material from the ring to balance the rotor in the upper plane. The balancing ring is on the same radius as the rotor tube cavities and of width less than the diameter of said cavities such that the ring, when the tube cavities are drilled, is broken into segments of precisely known area which make the amount of material to be removed to balance the rotor readily determinable.

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: An automatic chemistry analyzer comprises discrete sample cups about the circumference of a carousel. A motor selectively moves the sample cups towards and away from a target location where a probe is located for reciprocal vertical motion. The motion is timed for reaction with a sample cup so that when the sample cup is in position at the target location, the probe removes fluid from the sample cup. When the sample cup is moved from position, the probe aspirates fluid into an injection cell below the sample cup. A vertical motion only is imparted to the probe, while the sample cups move under the action of a single motor horizontally and laterally to define a rotational movement.

Abstract: Disclosed herein are buffers and methodologies for the capillary zone electrophoretic analysis of hemoglobin and the variants of hemoglobin. In a particularly preferred embodiment, the buffer comprises at least about 100 mM of barbituric acid, derivatives of barbituric acid, combinations of barbituric acid and the derivatives of barbituric acid, and combinations of the derivatives of barbituric acid, and has a pH of at least about 8.0.

Abstract: A cartridge for holding a capillary for electrophoresis. The cartridge has a body defining a passage along which the capillary is threaded. Exits are provided on the body for extending the ends of the capillary to access external fluid sources. The same cartridge may be used for different lengths of capillaries. An aperture is provided on the cartridge for optical detection of electrophoretic separation in the capillary held in the cartridge. The cartridge may include a hollow space defined about the capillary for circulating coolant fluid.

Abstract: A novel bidentate conjugate has two different chemical moieties, or bidentate members, attached through an adequate spacer moiety. Each bidentate member acts as a small molecule ligand and is capable of specifically binding to a different macromolecular substance. The bidentate members are relatively small molecules, usually less than about 7,000 Daltons in size. The spacer moiety is selected so that both bidentate members can simultaneously bind to their respective specific binding partners. Where the specific binding partners are multivalent, large complexes can be formed. The formation of these complexes can be inhibited by the presence of an unconjugated monovalent bidentate member, such as free analyte from a test sample. The bidentate is of particular use in turbidimetric or nephelometric inhibition immunoassay procedures.

Abstract: An automatic chemistry analyzer includes sample cups circumferentially located on a sample wheel. Means moves the sample cups rotationally under cycloidal action to and away from a target location where a probe operates vertically in relation to the sample cups and an injection cell. The motion is effected by a cam operating with a cam follower formed by lobes circumferentially located about a drive wheel which houses the sample wheel or carousel.