Ciba-Geigy Corporation

Spectra-Physics Gmbh

Thermo Separation Products (California) Inc.

Other

Vance J Nau

Andre J Nohl

Andre Metzger

Peter Grimm

Ronald Alan Gatten

Leslie A Miller

Thomas J McCall, Jr

Keith H Grant

Chih-Hua Chung

Ronald E Honganen

Les A Miller

A degassing system is provided and includes a module for conditioning a liquid to be analyzed. The module includes a container holding a liquid, a degassing chamber, and a holder for the liquid container mounted on top of the degassing chamber. The holder provides stability to the module and contains any liquid spills. In another embodiment, the system includes an autosampler in conjunction with a degassing unit which includes a degassing chamber, a vacuum pump, and tubing for conducting liquid through the degassing chamber, which tubing is permeable to gases in the liquid.

Methods and apparatus for degassing a liquid

An apparatus for effective vacuum degassing of a liquid is provided for liquid chromatography applications. The liquid to be degassed is heated in the vacuum chamber by a radiator of electromagnetic energy, in one embodiment, or is heated before it enters the vacuum chamber. The liquid may also be agitated while in the vacuum chamber. In a preferred form, the vacuum degassing unit includes a vacuum chamber including a vacuum pump for creating a vacuum therein, a source of liquid, and gas permeable tubing for conducting the liquid through said vacuum chamber. The tubing includes first and second larger diameter blocks having at least one hole therein interconnected by at least one length of small diameter tube to form a leak-tight seal therewith.

Methods and apparatus for effective vacuum degassing of a liquid are provided for liquid chromatography. The bottles with the liquid are mounted above the vacuum degassing unit to provide a head pressure to the LC pump and physical stability to the bottles. The liquid is heated in the vacuum chamber by a radiator of electromagnetic energy (in one embodiment, infra-red light). Alternatively the liquid is heated before it enters the vacuum chamber. The liquid is in an agitated state in the vacuum chamber. In one variation, the liquid is conducted through the vacuum chamber through tubes wound around bobbins so as to expose a greater portion of the surface area of the tubes to vacuum. Circuitry stops the vacuum pump for a duration of a chromatographic run. The circuitry controls the LC pump and the vacuum pump so as to optimize the chromatographic conditions in the liquid chromatography analytical system. The autosampler of the analytical system includes a vacuum degasser for degassing the resident solvents of the autosampler. Alternatively, the vacuum degassing unit for degassing the mobile phase is used to degas the resident solvents. The analytical system has its own vacuum chamber for extracting a gas from the sample to be analyzed. The extracted gas is used to produce chromatographic information. Components of a mixed solvent are mixed before the solvent is degassed. The vacuum chamber of the degassing unit is used in one variation to dissolve a selected gas in a mobile phase for use in chromatographic analysis. A method is provided for testing a conduit for conducting a liquid through the vacuum chamber. A selected gas is put in the conduit instead of the solvent, a vacuum level is created, and the time of decay of the vacuum level is measured to determine the contamination of the walls of the conduit.

Apparatus for degassing a liquid

A system for controlling an electromechanical system comprised of a number of electromechanical devices such as solenoid operated valves, motor, relays and other devices. The control system is comprised of a central processing unit and control software plus suitable interface circuitry to convert the digital data from the central processing unit into suitable control signals to operate the electromechanical devices. The control software is characterized by the ability to allow users to either select preprogrammed sequences of commands to be executed by the computer or to program unique sequence at either of two levels of complexity. User access privileges may defined by the system manager such that certain users may not be allowed to program their own sequences, while other users may be allowed to program their own sequences only on the first level of complexity but not the second, while a third group of users may be allowed to program on either of the programming levels or to run the preprogrammed sequence as defined by the system manager. The two levels of programming complexity are a high level and an expert level where the command set on the high level consists of a plurality of commands each of which represents a macro.

Control system for a sample preparation system

There is disclosed herein an automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking to the location of solid or very viscous samples. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogeneous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cup to allow pump of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a known volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration. A reversible pump is coupled by a pair of manifolds which are themselves coupled by solenoid operated valves to various sources of solvents, pressurized gas, vacuum, water, the sample preparation chamber and the assay system. A control system coordinates the operation of all remotely controllable units in the system to allow the user to customize various preparation processes.

System for preparation of samples for analysis

The two levels of programming complexity include a high level and an expert level. The command set on the high level includes a plurality of commands which comprise sequences of more detailed commands from the expert level. The expert level commands comprise single actions or operations, or small groups of operations, to be performed by the electromechanical devices, such as valve openings or closures. User access privileges are definable by a system manager to restrict different classes of users to one or more of the levels of complexity.

There is disclosed a sample preparation chamber for a system for preparing samples of various compositions for assay by liquid chromatography. The sample preparation chamber is includes a container having a threaded cap and a threaded, lightweight, translucent plastic cup. A stirrer/grinder shaft driven by a motor and connected to a propeller/grinder passes through the cap. The cup has a sloped bottom with a sump region, and a fill/empty pipe passes through the cap and has its outlet at or near the sump. A nozzle/fill pipe arrangement allows the walls to be washed down as liquid is pumped into the cup. A second fill pipe with its outlet spaced up from the bottom of the cup is also used, and a sample metering valve having an inlet in said cup is present. The sample metering valve is used to isolate a known volume of the sample from the rest of the sample for release back into the cup after the remaining sample has been pumped to waste for purposes of diluting the known volume of sample to a known concentration.

Sample preparation chamber with mixer/grinder and sample aliquot

There is disclosed a maintenance reminder system for a pump. The system of the invention is coupled to the pump or the control system for the pump and determines the volume of fluid pumped by the pump. In the preferred embodiment, a piston pump is used and piston strokes are counted and converted to total volume of liquid pumped. The computer of the system maintains a database for each maintenance item containing the threshold value for each item and the total volume pumped since the last maintenance. When the total volume exceeds the threshold, a maintenance reminder is displayed and the user may display information from the database as to which item needs service. The computer updates the appropriate fields of the database after the service is performed.

Maintenance reminder system for a pump

An automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking solid or very viscous samples to the sample preparation system. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogeneous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cup to allow pumping of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a known volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration. A reversible pump is coupled by a pair of manifolds which are themselves coupled by solenoid operated valves to various sources of solvents, pressurized gas, vacuum, water, the sample preparation chamber and the assay system. A control system coordinates the operation of all remotely controllable units in the system to allow the user to customize various sample preparation processes.

Process for preparation of samples for analysis

A sample metering valve for both liquid samples and slurry samples with entrained gas bubbles. The sample metering valve for liquids is comprised of a piston with sample chambers formed in the side thereof said piston moving freely into and out of a cylinder having an aperture matching the size of the piston. Sealing is provided by a seal which has no dead volume which cold flows under a spring bias to maintain the seal under various operating conditions. The sample metering valve for slurry samples includes a syringe embodiment having separately moving piston and valve in a cylinder. The syringe valve sucks up sample with a piston, isolates the sample with the valve and compresses the entrained gas bubbles with the piston. Another embodiment uses three, three way valves which are coupled to a pump and a means to compress the sample. The valves are operated to suck a portion of sample up into the tubes connecting the valves, isolate the sample from the sample container, compress the sample using the compressed gas and trap a known volume of the compressed sample in the tube between valves. The trapped sample is then flushed out of the system with diluent to prepare the sample for analysis.

Sample metering valve for a sample preparation system

An automated sample preparation system for chemical assay of samples of materials. The sample preparation system includes a sample preparation chamber which includes a removable cup for taking solid or very viscous samples to the sample preparation system. The cup may be attached in sealing relationship to a cap through which extends various utilities such as a mixer/grinder to grind solid samples and mix non-homogenous samples, a fill pipe to pump in liquid samples, an effluent pipe in the sump of the cap to allow pumping of samples and solvents and a nozzle to allow liquids to be sprayed against the walls. A sample metering valve associated with the sample preparation chamber allows a know volume of sample to be isolated so that solvent may be pumped in to dilute the sample to a user defined concentration. A reversible pump is coupled by a pair of manifolds which are themselves coupled by solenoid operated valves to various sources of solvents, pressurized gas, vacuum, water, the sample preparation chamber and the assay system. A control system coordinates the operation of all remotely controllable units in the system to allow the user to customize various ample preparation processes.

There is disclosed a sample preparation chamber for a system for preparing samples of various compositions for assay by liquid chromatography. The sample preparation chamber is a container having a threaded cap and a threaded, lightweight, translucent plastic cup. A stirred/grinder shaft driven by a motor and connected to a propeller/grinder passes through the cap. The cap has a sloped bottom with a sump region, and a fill/empty pipe passes through the cap and has its outlet at or near the sump. A nozzle fill pipe arrangement allows the walls to be washed down as liquid is pumped into the cup. A second fill pipe with its outlet spaced up from the bottom of the cup is also used, and a sample metering valve having an inlet in said cup is present. The sample metering valve is used to isolate a known volume of the sample from the rest of the sample for release back into the cup after the remaining sample has been pumped to waste for purposes of diluting the known volume of sample to a known concentration.

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Cupertino, CA, United States of America

Vance J Nau