Apparatus for producing thin liquid samples for microscopic analysis

• US 6,599,475 B1
• Filed: 09/27/2000
• Issued: 07/29/2003
• Est. Priority Date: 09/27/2000
• Status: Expired due to Fees

• Current Assignee: Becton, Dickinson & Co
• Original Assignee: Becton, Dickinson & Co
• Inventors: Berndt, Klaus W., Livingston, Dwight, Scrivens, Brian G., Frank, Robert S.
• Primary Examiner(s): Warden, Jill
• Assistant Examiner(s): SINES, BRIAN J
• Application Number:
  US09/671,132
• Time in Patent Office: 1,035 Days
• Field of Search: 422/99, 422/50, 422/68.1, 422/82.05, 422/102, 422/73, 422/100, 422/101, 422/104, 422/44, 422/72, 430/180, 436/526, 436/69, 356/246
• US Class Current: 422/401
• CPC Class Codes: G01N 1/2813 Producing thin layers of samples on a substrate, e.g. smearing, spinning-on G01N1/30 takes precedence
• CPC Class Codes: G01N 2021/0346 Capillary cells; Microcells
• CPC Class Codes: G01N 21/03 Cuvette constructions
• CPC Class Codes: Y10T 436/25 including sample preparation
• CPC Class Codes: Y10T 436/25375 Liberation or purification of sample or separation of material from a sample [e.g., filtering, centrifuging, etc.]
• CPC Class Codes: Y10T 436/2575 Volumetric liquid transfer

Abstract

The present invention relates to the field of diagnostics by means of microscopic sample analysis, and specifically relates to a method and apparatus for preparing thin microscopic samples of liquids, and in particular monolayers of red blood cells.

Claims

1. An apparatus for producing thin samples of liquids for microscopic analysis, said apparatus comprising:

a base portion;

a means for containing said sample(s) carried by said base portion, having an interior, an exterior, and outside walls; and

a lid portion,

the base portion, said means and the lid forming a cuvette,

wherein said cuvette has a plurality of consecutive separation walls which separate the interior of said cuvette into a plurality of successive compartments;

wherein said cuvette has a sample entrance port that is connected with the first of said successive compartments by a channel,

wherein each of said consecutive separation walls comprises at least two different types of through-channels, and

wherein the liquid sample is analyzed within the last of said successive compartments.

2. The apparatus according to claim 1 wherein said liquid is blood.

3. The apparatus according to claim 1 wherein said base portion is a base plate.

4. The apparatus according to claim 2 wherein said cuvette has a thickness small enough so that for a sample of undiluted whole blood entering said entrance port, and passing through all of said through-channels in said consecutive separation walls between said successive compartments, the average distance between neighboring red blood cells in the last of the successive compartments is greater than the typical red blood cell diameter.

5. The apparatus according to claim 1 wherein said cuvette has a thickness of between about 3 and 10 μ

m.

6. The apparatus according to claim 2, wherein each separating wall of said cuvette comprises:

a) at least one through-channel of a first type which allows red blood cells and blood plasma to flow through said wall; and

b) at least one through-channel of a second type which allows only blood plasma to flow through said wall.

7. The apparatus according to claim 1 wherein each wall of each compartment of said cuvette has at least one small venting opening for air venting.

8. The apparatus according to claim 2 wherein each wall of each compartment of said cuvette has at least one small venting opening for air venting.

9. The apparatus according to claim 1 wherein said base plate is comprised of polycarbonate or polystyrene.

10. The apparatus according to claim 1 wherein said sample entrance is a sample entry port in the base portion which is connected to the means by a narrow channel.

11. The apparatus according to claim 1 wherein said separating walls of said means have weld features.

12. The apparatus according to claim 11 wherein said outside walls of said means are surrounded by a moat, so that the lid portion rests only on the outside walls and weld features.

13. The apparatus according to claim 1 wherein said lid portion is a transparent lid.

14. The apparatus according to claim 13 wherein said transparent lid is made out of plastic material.

15. The apparatus according to claim 11 wherein said lid portion is welded onto the outside walls and weld features of said means.

16. The apparatus according to claim 13 wherein said base plate is comprised of a transparent plastic material, providing said cuvette with two windows for performance of transmission measurements.

17. The apparatus of claim 2 wherein said separation walls are arranged in consecutive longitudinal fashion.

18. The apparatus of claim 1 wherein said sample container has at least five separating walls.

19. The apparatus of claim 2 wherein said cuvette has at least one window for performance of fluorescence measurements.

20. The apparatus of claim 2 wherein said cuvette has at least two windows for performance of transmission measurements.