A channel-cell system is provided for detecting the presence and/or measuring the presence of analyte particles in a sample stream comprising a laminar flow channel (100), two inlet means (30, 20) in fluid connection with said laminar flow channel (100) for respectively conducting into the laminar flow channel (100) an indicator stream (70) which may comprise an indicator substance which indicates the presence of said analyte particles by a detectable change in property when contacted with said analyte particles, and the sample stream (80), wherein the laminar flow channel (100) has a depth sufficiently small to allow laminar flow of the streams and a length sufficient to allow particles of the analyte to diffuse into said indicator stream (70) to the substantial exclusion of said larger particles in the sample stream (80) to form a detection area; and outlet means (60) for conducting the streams out of the laminar flow channel (100) to form a single mixed stream.

Microfabricated diffusion-based chemical sensor

This invention provides a microfabricated extraction system and methods for extracting desired particles from a sample stream containing desired and undesired particles. The sample stream is placed in laminar flow contact with an extraction stream under conditions in which inertial effects are negligible. The contact between the two streams is maintained for a sufficient period of time to allow differential transport of the desired particles from the sample stream into the extraction stream. In a preferred embodiment the differential transport mechanism is diffusion. The extraction system of this invention coupled to a microfabricated diffusion-based mixing device and/or sensing means allows picoliter quantities of fluid to be processed or analyzed on devices no larger than silicon wafers.

Microfabricated differential extraction device and method

Embodiments are directed to portable infusion devices, systems, and methods of using the same for dispensing materials. In some cases, the devices, systems and methods may be used for infusing a material such as medicament, e.g., insulin, into a body in need thereof.

Infusion pump system with disposable cartridge having pressure venting and pressure feedback

This invention provides microfabricated systems for extraction of desired particles from a sample stream containing desired and undesired particles. The sample stream is placed in laminar flow contact with an extraction stream under conditions in which inertial effects are negligible. The contact between the two streams is maintained for a sufficient period of time to allow differential transport of the desired particles from the sample stream into the extraction stream. In a preferred embodiment the differential transport mechanism is diffusion. The extraction system of this invention coupled to a microfabricated diffusion-based mixing device and/or sensing means allows picoliter quantities of fluid to be processed or analyzed on devices no larger than silicon wafers. Such diffusion-based mixing or sensing devices are preferably channel cell systems for detecting the presence and/or measuring the quantity of analyte particles in a sample stream.

Microfabricated devices and methods

To collect analyte in a supercritical fluid extraction process, the extractant flows to a collection container (130) under pressure. In one embodiment, the collection container (130) contains collection solvent (144) through which the extractant flows to partition analyte. The extractant adds to the liquid and when the collection solvent-extractant mixture rises to a heating zone, the extractant vaporizes selectively since its vapor pressure is higher than the vapor pressure of the collection solvent (144). When its pressure exceeds a preset valve (148) pressure it is vented so that extractant continually leaves the collection container (130). After the extraction is complete, the analyte is concentrated in the collection solvent (144). In another embodiment, the collection vessel includes a solid material on which the analyte collects. It is removed under pressure by a solvent that is concentrated under pressure.

Apparatus and method for supercritical fluid extraction

Methods and apparatus for extracting sample components from complex matrices using supercritical fluid as the principal extracting solvent are disclosed. The invention takes advantage of the fact that the solvent power of a supercritical fluid is stepwise settable by the parameters of density, modifier concentration, and temperature. Accordingly, methods and apparatus for extracting a component from a sample using fluid flow system having a variable and controllable flow restriction are disclosed. The methods of the present invention comprise the steps of inserting the sample into the sample container section, inputting temperature, pressure, flow rate and extraction time set points. Flow rate is controlled and system pressure regulated by the variable flow restriction. The output stream from the extraction is then expanded through a nozzle and into a trap. In certain embodiments, the trap is filled with chemically active packing material. In other embodiments, a fractionation zone and other analytical instruments are coupled to the apparatus of the present invention. Methods and apparatus for rinsing the extraction instrument and for diluting the extraction fluid are also disclosed. Methods for operating a supercritical fluid extraction systems comprising a pressure and thermal control systems which are programmable to regulate the system to maintain such values within the design specifications during the extraction process.

Decoupled flow and pressure setpoints in an extraction instrument using compressible fluids

A solenoid driven valve is disclosed which is adaptable for controlling the introduction of a high pressure fluid into a fluid trapping assembly having an absorption column topped with an annular orifice expansion nozzle. The valve has an inlet port to introduce high pressure fluid, an axially moving solenoid driven pin which engages means to restrict fluid flow into said column. A diaphragm is located within the valve to direct fluid into the column and which separates the fluid in a region of high pressure from ambient pressures.

Axially-driven valve controlled trapping assembly

Axially-driven valve controlled fluid trapping assembly

Method and apparatus for regulating the passage of fluid through a chamber or other type of conduit. Fluid passage is terminated when the volume of fluid which has swept through a chamber equals a selected multiple of the chamber's internal volume, which multiple is known as swept chamber volumes.

Method and apparatus for regulating fluid flow

Methods and apparatus for adding modifiers to bulk extraction fluids of supercritical fluid extraction devices are disclosed. The bulk fluid and modifiers are either provided from separate sources (100,102) or a pre-mixed source (300) and are preferably introduced into an extraction system using a pump (310) or set of pumps 130,132 that include sensors (130,132,330) and a controller (120,320). By controlling the temperature and pressure of the mixture has now been found that the gas/liquid interface of the modifier on the sample can be controlled. In other words the vapor-liquid equilibria (VLE) is "tuned" to control the liquid and vapor composition within the sample container. Preferably, the conditions are controlled so that the modifier exists as a liquid within the sample container (210) and be effective to enhance the extraction.

Lenore R Frank

Papers

Decoupled flow and pressure setpoints in an extraction instrument using compressible fluids

Axially-driven valve controlled trapping assembly

Axially-driven valve controlled fluid trapping assembly

Method and apparatus for regulating fluid flow

Methods and apparatus for automatically adding fluid reagents to sample containers.