Beckman Instruments, Inc.

Beckman Coulter, Inc.

Dobson M Okawa

Wing S Pang

Peter Kan

George K Shibata

Dang Minh Ngo

William Weigong Li

Rongchang Xin

Paul E Theobald

Daniel B Seymour

William W Li

Method and apparatus for controlling the temperature of one or more reaction vessels in a bio-chemical analyzer comprises a heat-exchange block, preferably made of cast aluminum or the like, and a thermoelectric device for heating or cooling the block to within a desired temperature range. The heat-transfer block cradles one or more reaction vessels in a thermal energy-transferring relationship, and further supports, in a thermal energy-transferring relationship, one or more fluid conduits serving to transmit a liquid or gas to the interior of the reaction vessels. Preferably, the heat-transfer block is cast from aluminum, and the fluid conduits are disposed inside the casting. By supporting the reaction vessel(s) and fluid conduit(s) in a common block, a single thermoelectric device and controller can be used to simultaneously control the respective temperatures of multiple fluid reagents and/or gases, as well as one or more reaction vessels, thereby reducing the power requirements of the thermal control system.

Method and apparatus for controlling reaction temperature in bio-chemical instruments

A system for analyzing a chemical reaction provides control of the temperature and volume of the reagents to improve the accuracy and precision in quantitative measurements of specific proteins and other immunochemistries in body fluids. The reaction occurs in a cuvette within a nephelometric optics module. A sensor senses the temperatures of reaction buffer liquids as they flow into the cuvette, and a heat exchanging device increases or decreases the temperatures of the buffer liquids. A control circuit responsive to the temperature sensor controls the heat exchanging device to maintain the temperature of the buffer liquids and the cuvette within a selected temperature range. The system may also include a sample pickup station, a sample probe for withdrawing a selected sample from the sample pickup station, a sample preparation station, and a sample transport for carrying said sample from the sample preparation station to the reaction cuvette. The system may include an antibody pickup station, an antibody probe for withdrawing an antibody from the antibody pickup station, an antibody preparation station, and an antibody transport for carrying the antibody from the antibody preparation station to the reaction cuvette.

Method of performing nephelometric analysis with independent temperature

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.

Apparatus and method for dynamic blanking of non-specific light

Apparatus for controlling reaction temperatures in a chemical analyzer comprises a thermoelectric element operating in response to a temperature sensor, and control means capable of predicting a setpoint deviation for a future time period, and, when an overshoot is predicted, reducing a control signal for the element by an amount proportional to a current setpoint deviation. The apparatus includes at least one reaction cell and a buffer unit for thermally stabilizing a fluid that is fed, on demand, into the reaction cell, the cell and the buffer unit having separate thermoelectric elements and sensors. A microcomputer control system generates independent control signals for the elements.

Reaction temperature control system

Apparatus for sensing liquid levels in fluid transfer mechanisms and the like comprises a conductive member supporting containers for sample liquids, the conductive member being rotatably mounted for positioning selected containers under a conductive pipette probe. A low-frequency oscillator is capacitively coupled to the conductive member for generating an alternating electric field and producing an electrical signal at the probe. As the probe is lowered toward the liquid, an amplifier circuit monitors an electrical signal received by the probe. When the probe contacts the liquid, the amplifier detects a signal level in excess of a threshold level and produces an output signal for inhibiting the downward movement of the probe at the moment of contact with the liquid.

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Anaheim, CA, United States of America

Dobson M Okawa