Apparatus for pumping and directing fluids for hematology testing

• US 7,294,307 B2
• Filed: 10/27/2004
• Issued: 11/13/2007
• Est. Priority Date: 01/21/1993
• Status: Expired due to Term

• Current Assignee: Drew Scientific Holdings, Inc.
• Original Assignee: Drew Scientific Holdings, Inc.
• Inventors: Carver, Edward Lawrence Jr.
• Primary Examiner(s): Soderquist; Arlen
• Application Number:
  US10/975,189
• Publication Number:
  US 20050169802A1
• Time in Patent Office: 1,112 Days
• Field of Search: 422/67, 422/73, 422/81, 422/100, 436/8, 436 17- 18, 436/52, 436/63, 436/66, 436174-175
• US Class Current: 422/73
• CPC Class Codes: G01N 15/1409 Handling samples, e.g. injecting samples
• CPC Class Codes: G01N 35/1095 for supplying the samples to flow-through analysers for a specific analyser see relevant groups, e.g. under G01N15/00, G01N21/00, G01N27/00, G01N30/00, H01J49/00
• CPC Class Codes: Y10T 436/10 Composition for standardization, calibration, simulation, stabilization, preparation or preservation; processes of use in preparation for chemical testing
• CPC Class Codes: Y10T 436/107497 Preparation composition [e.g., lysing or precipitation, etc.]
• CPC Class Codes: Y10T 436/108331 Preservative, buffer, anticoagulant or diluent
• CPC Class Codes: Y10T 436/117497 with a continuously flowing sample or carrier stream
• CPC Class Codes: Y10T 436/25 including sample preparation
• CPC Class Codes: Y10T 436/25125 Digestion or removing interfering materials

Abstract

An apparatus is provided for hematology testing, which has a sensing unit defining a counting orifice for the flow of a blood sample through the counting orifice to analyze the blood sample, and a pump unit having three syringes. A first syringe is coupled in fluid communication with the sensing unit on the inlet side of the counting orifice for injecting a stream of blood sample through the counting orifice. A second syringe is coupled in fluid communication with the sensing chamber on the inlet side of the counting orifice for simultaneously injecting a sheath of fluid surrounding the sample stream on the inlet side of the counting orifice. And a third syringe is coupled to the sensing chamber on the outlet side of the counting orifice for aspirating a sheath of fluid from the sensing chamber surrounding the sample stream on the outlet side of the counting orifice.

Claims

1. An apparatus for analyzing blood, the apparatus comprising:

a pump;

a reagent chamber for containing a lysing agent, the reagent chamber is in fluid communication with the pump;

a control unit is adapted to adjust a ratio of the lysing agent to blood, the control unit is in electrical communication with the pump and includes a database of predetermined quantities of each of a plurality of reagent-mixture components, and each predetermined quantity corresponds to a respective species;

a mixing zone for mixing the ratio of the lysing agent and blood to create a reagent mixture, the mixing zone is in fluid communication with the reagent chamber; and

a sensing zone for receiving the reagent mixture and analyzing a particle distribution of the reagent mixture, the sensing zone is in fluid communication with the mixing zone.

2. The apparatus of claim 1, wherein the reagent mixture remains in the mixing zone for a predetermined amount of time.

3. The apparatus of claim 1, wherein the sensing zone includes a transducer.

4. The apparatus of claim 3, wherein the transducer is adapted to detect differences in optical characteristics in each of the cells of the reagent mixture.

5. The apparatus of claim 3, wherein the transducer is adapted to detect differences in electrical characteristics in each of the cells of the reagent mixture.

6. The apparatus of claim 1, wherein the control unit is adapted to adjust the ratio of the lysing agent to blood in response to an operator input.