Abstract:
A refrigerant tubing (34) is preformed to provide a flat contact surface (42) against the outside surface of a centrifuge chamber (32). The tubing (34) is tightly wound around the centrifuge chamber (32) in a continuous fashion including a flat spiral (46) at the base (33) of the centrifuge chamber. For the section of the tubing in contact with the vertical cylindrical wall (35) of the centrifuge chamber (32), the pressure for maintaining contact pressure between the flat surface (42) of the tubing (34) and the chamber wall (35) is provided by the tension in the wrapping of the tubing (34). For the section of the tubing (34) at the base (33) of the centrifuge chamber (32), contact pressure may be provided by a clamping mechanism (58). To further enhance heat transfer between the refrigerant coils and the centrifuge chamber (32), a high heat conductive epoxy (44) may be applied between the tubing (34) and the centrifuge chamber surface.
Abstract:
Disclosed are antibodies to derivatives and variants of Streptolysin O ("SLO"). Methodologies for generating such antibodies are further disclosed, as are purification protocols for wild-type SLO and assaying techniques for wild-type SLO.
Abstract:
A method and specimen slide (10) for collecting fecal specimens for occult blood testing. The slide includes a front panel (12) and back panel (14). The front panel (12) includes an aperture (18). A sheet (20) is fixed between the front (12) and back (14) panels and is positioned for receiving the fecal specimen smear through the aperture (18). The sheet (20) includes a plurality of perforations (22) that define removable portions (24) of the sheet. The hinged cover (16) can close the front panel aperture (18) and a flap (36) in the rear panel (14) may be opened to conveniently remove one or more of the removable portions (24) for testing.
Abstract:
A method of scintillation counting utilizes a solid scintillator dispersed on a counting support (16), wherein a sample material is deposited on the counting support over the solid scintillator to produce light emissions in response to particles emitted by a radio-active substance labelling said sample.
Abstract:
A novel agarose gel is provided for use in the high resolution electrophoretic (HRE) separation of serum proteins. The agarose gel employs a novel gel buffer which contains either hippurate, glycine, or a mixture thereof, in combination with barbital and Tris. The agarose gel of the present invention yields improved electrophoretic separation of the serum proteins in a sample whether the same gel buffer is also used as the running buffer or whether a standard barbital running buffer is used.
Abstract:
To enable centrifuging to occur at precisely determined sample temperatures, a method of calibration, of the measured rotor temperature, which permits rapid and accurate refrigeration of the rotor containing the sample, is disclosed. A rotor (R, R1) with sample to be centrifuged is placed within a centrifuge can (C). Temperature of the radiometer (T), Tra, and temperature of the surrounding refrigerating can Tc is determined at a first time, t0. Thereafter, and at a second time t1, temperature of the radiometer Tra, and the temperature of the surrounding refrigerating can Tc are equilibrated. The temperature excursion between t0 and t1 for the temperatures of the radiometer Tra and the temperature of the refrigerating can Tc are measured to yield respective DELTA Tra and DELTA Tc. The ratio of DELTA Tra/DELTA Tc is taken to give a constant which comprises the ''view factor'' (u) from the radiometer for the particular shape of rotor and the surrounding can. Thereafter, the temperature of the rotor (Tr) will equal the temperature of the radiometer plus the difference in temperature between the refrigerating can (Tc) and the radiometer (Tra), times the determined view factor. It is thereafter possible to maintain a large temperature differential between the refrigerating can and the rotor and bring the rotor (and necessarily the sample) rapidly to a precise temperature where centrifuging can rapidly follow.
Abstract:
A method for detecting a polynucleotide in a sample comprising: combining in liquid phase the sample with a first and second probe, each binding to different sequences of the target polynucleotide. The ''target/probe'' complex is immobilized subsequently with a solid carrier able to bind the first probe. The second probe carries a detectable label. A kit for use with the method and the use thereof for the diagnosis of genetic diseases, such as sickle cell anaemia, and for cancer is disclosed.
Abstract:
An automated multi-purpose analytical chemistry processing center and laboratory work station having a movable table (28) for supporting microtiter plates (27) and other fluid receptacles, a movable arm (44), and a modular mobile pod (42) affixed for reciprocal movement along the arm (44). 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. The work station is capable of measuring physical characteristics of selected samples and performing experimental assays in a closed loop manner in accordance with those measurements. Fluid is dispensed and aspirated using an interchangeable modules (52) having one or a selected plurality of nozzles (54). Affixed to the modules nozzles are disposable pipettor tips (56), which are automatically picked up by the pod (42) and ejected by a tip ejector mechanism (58) at the control of the user. Additional modules may be used to perform Measurement Functions. The work station is designed for interactive connection with a remote computer.
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 for a scatter signal 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 mixing valve includes a housing having inlet ports (14, 16) and an outlet port (18) that intersect at a valve chamber. A valve core (20) within the valve chamber includes passages (34-36) in fluid communication with the inlet and outlet ports. The passages intersect at a cavity (38) within the valve core. An elastomeric seal (44) retained within the cavity sealingly engages the valve core around the passages in the absence of fluid pressure in the inlets. Injection of a pressurized fluid in one of the inlets causes the seal to move away from both the corresponding inlet passage to permit fluid flow from the pressurized inlet port to the outlet port and compresses the seal around the other inlet port to provide a tighter seal than existed before application of pressure to the first port.