Ciba-geigy Corporation

Spectra-physics Gmbh

Other

Spectra-physics Analytical, Inc.

Andre J Nohl

Vance J Nau

Andre Metzger

Peter Grimm

Thomas J McCall, Jr

Landy B White

Ronald V Perkins

A syringe of relatively simple construction which is capable of both accurate and reproducible sample volume withdrawals, including volumes of 1.0 .mu.l or less, is provided. The syringe drive mechanism is preferably adapted for use in a liquid sampling apparatus and includes a threaded lead screw, a drive for rotating the screw, and a syringe having a plunger for withdrawing a liquid sample. The plunger is mechanically connected to the rotating lead screw by a nut threaded onto the screw and a slider mechanism associated with the nut which also is secured to the plunger. The nut is designed so that lateral misalignment of the drive screw does not affect the precise linear movement of the slider mechanism, and consequently, the plunger. This provides a mechanism which is less expensive to assemble and align properly, but which has a high degree of accuracy and reproducibility.

Syringe drive with lead screw mechanism

A heater/mixer device is disclosed for use with laboratory vials, test tubes, or similar containers containing liquids. The heater/mixer includes a chamber formed in a block of material such as aluminum, with an electric heating element in contact with the block. The vial fits loosely in the chamber. Compressed air passes into the chamber through an inlet in the block, so that the vial is revolved by a circular air flow in a vortex fashion. This revolving motion creates a vortex in the liquid inside the vial, and so mixes the liquid. The air circulation also improves heat transfer from the block to the vial.

Air powered heater/mixer

A conventional injection valve, such as used in high performance liquid chromatography apparatus, having six ports and three channels for connecting the ports in two different positions, is modified so that one of the channels is longer than the other two. In this way, when the valve is switched to the load position, one of the ports is always connected to the channel prior to the other port being connected. This improvement in the valve makes the valve more accurate and reduces undesirable mixing of sample and mobile phase in the valve when injecting small quantities of sample.

Nonsymmetrical valve

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

A pushloop liquid sampling method is an improvement in the method of introducing liquid samples into test equipment (such as for liquid chromotography) via a six port valve. The method involves pulling the sample completely past the sample loop in the six port valve and then pushing the desired amount of sample back into the sample loop.

Pushloop liquid sampling method

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

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 process removes FMOC--OH which is an undesirable by-product of the derivatization of amino acids by FMOC. The process uses a silicone rubber membrane extractor cell. The sample containing the FMOC--OH is held in a silicone rubber tubing, while pentane flows past the outside of the tube; the FMOC--OH is thus extracted from the sample into the pentane. The process is integrated into a conventional high performance liquid chromatography system and is readily automated.

Method and apparatus for membrane extraction of hydrolysis contaminates

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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Menlo Park, CA, United States of America

Andre J Nohl