Abaxis, Inc.

Tammy L Burd

Carol T Schembri

Steven N Buhl

Vladimir E Ostoich

Boris Braynin

Chi-Sou Yu

Bhaskar Bhayani

Thuy N Tang

Branko Huc

Christian Skieller

Terri Bogart

The present invention provides lyophilized reagent spheres comprising reagents suitable for analysis of biological samples, in particular analysis of blood samples in centrifugal analyzers. Also provided are diluents which are conveniently used in such analyzers.

Reagent compositions for analytical testing

The present invention provides centrifugal rotors for delivering a liquid, typically a biological sample such as diluted plasma, to a plurality of cuvettes in the rotor. The cuvettes are positioned radially inward of an annulate manifold and are connected to the manifold through a plurality of inlet channels. The liquid is introduced in one end of the manifold and, as the rotor spins, the liquid fills the manifold from the radially outward edge inward. After, the manifold fills, the liquid flows radially inward through the inlet channels into the chambers. The design allows the simultaneous filling of the cuvettes. The inlet channels may also be sized such that as liquid enters the cuvettes, gas escapes through the inlet channel.

Simultaneous cuvette filling with means to isolate cuvettes

An analytical rotor which comprises a receptacle for receiving a post on a centrifuge and means in the rotor body proximate to the receptacle for releasing a liquid in response to mounting the rotor in the centrifuge is disclosed. The means for releasing the liquid is preferably a sealed container shiftably positioned in a chamber proximate the receptacle.

Reagent container for analytical rotor

An analytical rotor which comprises a receptacle for receiving a post on a centrifuge and a sealed rigid container in the rotor body proximate to the receptacle is provided. The seal on the container is opened when the post is inserted in the receptacle, thereby releasing a liquid in the container. The seal is preferably opened through the displacement of the container caused by positioning of the rotor on the centrifuge post.

An analytical rotor for separating plasma whole blood comprises a rotor body having a sample application port in an upper surface thereof. Blood introduced to the sample application port is metered into a metering chamber by capillary flow while the rotor remains stationary. Excess blood passes into an overflow chamber by capillary flow, either simultaneously with the metered flow or after opening of a vent in the overflow chamber. Subsequent rotation of the rotor causes metered blood in the metering chamber to flow into a receiving chamber, typically a plasma separation chamber.

Sample metering port for analytical rotor having overflow chamber

An analytical rotor for separating cellular components from a biological fluid includes a separation chamber spaced radially outward from a sample chamber. The sample chamber may be an open receptacle disposed to receive sample or may be a mixing chamber which receives sample and diluent. A flow restrictive channel connects the sample chamber to the separation chamber so that fluid enters the separation chamber at a controlled rate. The cellular components collect within a retention region located generally at the outer periphery of the collection chamber while cell-free fluid is continuously removed through a collection port. The collection port is spaced annularly apart from the flow channel so that there is sufficient residence time within the separation chamber for substantially complete separation of the cells from the fluid fraction. In a first embodiment, a collection chamber is attached through the collection port through an annular flow channel, while in a second embodiment a collection chamber is connected through a vertical flow channel.

Apparatus and method for continuous centrifugal blood cell separation

A centrifugal rotor comprising a plurality of peripheral cuvettes and a collection chamber spaced radially inward from the cuvettes is disclosed. The rotor includes a means for introducing fluid into the collection chamber and plurality of generally radial inlet channels connecting each cuvette to the chamber. Each inlet channel has a discrete flow path for fluid to enter the cuvette and another discrete flow path for gas to exit the cuvette as the cuvette is filled. Positioned radially inward from each cuvette is a reflective surface capable of deflecting a light beam from a generally vertical direction to a generally horizontal direction or vice versa. As the rotor is spun, fluid enters the cuvettes from collection chamber through the inlet channels, which also allow gas in the cuvettes to escape, thus avoiding the creation of bubbles in the cuvette after the cuvettes are filled. The contents are then optically analyzed by passing a light beam horizontally through the cuvette.

Apparatus and method for optically analyzing biological fluids

A centrifugal rotor for separating plasma from whole blood includes a plurality of internal chambers and passages for combining the plasma with one or more reagents and distributing the plasma to a plurality of individual test wells. The chambers and passages necessary for separating the whole blood into plasma are located on a first, upper level within the rotor and include a measuring chamber, an overflow chamber, a separation chamber, and a reagent chamber. The measuring chamber and overflow chamber have capillary dimensions so that an initial volume of whole blood partitions therebetween, with the measuring chamber filling first to provide a preselected volume. The separation chamber is located radially outward from both the measuring chamber and the reagent chamber to that spinning of the rotor causes both the reagent and the measured blood volume to flow outward into the separation chamber. The separation chamber includes a radially-outward cell trap and a radially-inward drainage port so that spinning of the rotor causes the cellular components of the whole blood to enter the cell trap, while cessation of spinning allows the separated plasma to flow downward through the drainage port. A collection chamber is formed at a lower level than the rotor to receive the plasma through the drainage port. Further spinning of the rotor causes the plasma to flow radially outward into a plurality of test wells formed around the periphery of the collection chamber. Testing of the separated plasma volumes may be performed without removing the plasma from the rotor.

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Fremont, CA, United States of America

Tammy L Burd