Analyzer with improved rotor structure

• US 5,160,702 A
• Filed: 01/17/1989
• Issued: 11/03/1992
• Est. Priority Date: 01/17/1989
• Status: Expired due to Fees

• Current Assignee: Molecular Devices
• Original Assignee: Molecular Devices
• Inventors: Zuk, Robert, Kopf-Sill, Anne R.
• Primary Examiner(s): Warden, Robert J.
• Assistant Examiner(s): Trembley, T. A.
• Application Number:
  US07/297,563
• Time in Patent Office: 1,386 Days
• Field of Search: 422/72, 422/100, 436/45, 494/16, 494/17, 494/18, 494/21, 494/31
• US Class Current: 422/72
• CPC Class Codes: B01L 2200/0605 Metering of fluids
• CPC Class Codes: B01L 2300/0803 Disc shape
• CPC Class Codes: B01L 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2300/087 Multiple sequential chambers
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0409 centrifugal forces
• CPC Class Codes: B01L 3/502753 characterised by bulk separation arrangements on lab-on-a-chip devices, e.g. for filtration or centrifugation separation in general B01D; microapparatus for analysis using electrophoresis G01N27/44791; sample preparation G01N1/28
• CPC Class Codes: G01N 2035/00495 Centrifuges
• CPC Class Codes: G01N 2035/00524 Mixing by agitating sample carrier
• CPC Class Codes: G01N 21/07 Centrifugal type cuvettes G01N21/09 takes precedence
• CPC Class Codes: Y10T 436/111666 Utilizing a centrifuge or compartmented rotor

Abstract

An analyzer with an improved rotor structure for analyzing solid-containing and solid free liquids having an improved rotor design that utilizes chambers and channels that operate by centrifugal force and capillary action to separate and meter the liquids for testing purposes.

Claims

1. In an apparatus for analyzing fluids having components of different density, an improved analyzer rotor comprising:

a rotatable element mounted for rotation having interconnected chambers and channels disposed in the surface thereof,

said channels and chambers comprising

a mixing chamber,

a diluent capillary channel having one end connecting to said mixing chamber,

a blood chamber,

a curved separating channel in communication with said blood chamber for separating red cells from the plasma of whole blood,

said curved separating channel having one end spaced radially farther from the center of rotation than the opposite end thereof,

a plasma capillary channel connecting said curved separating channel to said mixing chamber,

a diluent metering chamber connecting to the other end of said diluent capillary channel, and

means for rotating said rotatable element at varying speeds to effect movement of fluids through said channels and to mix said separated plasma with diluent.

2. The apparatus of claim 1 in which said channels and chambers also include a sample sample cuvette, an air vent channel connecting to said cuvette and a siphon mix channel interconnecting said sample cuvette with said mixing chamber, said sample cuvette being spaced radially outwardly beyond said mixing chamber.

3. The apparatus of claim 2 which includes a diluent overflow chamber connecting to said diluent metering chamber, a control cuvette, an air vent channel connecting to said control cuvette, a siphon mix channel connecting said control cuvette to said diluent overflow chamber, said control cuvette being spaced radially outwardly from said diluent overflow chamber.

4. The apparatus of claim 3 in which a diluent holding chamber is interposed between said diluent overflow chamber and said siphon mix channel.

5. The apparatus of claim 4 in which said diluent holding chamber connects to said diluent overflow chamber through a diluent siphon capillary channel.

6. The apparatus of claim 1 in which said diluent capillary channel and said plasma capillary channel are generally V-shaped with one leg of the V being longer than the other, said legs extending outwardly toward the circumference of said rotatable element.

7. The apparatus of claim 6 in which said diluent capillary channel is larger in cross section than said plasma capillary channel.

8. The apparatus of claim 6 which includes a diluent overflow chamber connecting to said diluent metering chamber and a blood overflow chamber connecting to said blood chamber through a radial channel.

9. The apparatus of claim 1 which includes a cover over said rotatable element, a first opening through said cover communicating with said blood chamber, a second opening through said cover communicating with diluent metering chamber, and air vent openings communicating with chambers and channels which are vented.

10. The apparatus of claim 9 which includes a circular diluent inlet chamber between said second opening and said diluent metering chamber.

11. The apparatus of claim 10 wherein said inlet chamber has an outlet communicating with said diluent metering chamber and includes a passageway connecting said outlet to said diluent metering chamber and a diluent overflow chamber connecting to said passageway to receive fluid in excess of a predetermined quantity carried by said diluent metering chamber.

12. The apparatus of claim 10 in which said diluent metering chamber and said diluent overflow chamber communicate with air vents to permit filling thereof.

13. The apparatus of claim 1 which includes a vented fluid trap between said siphon mix channel and said sample cuvette.

14. The apparatus of claim 13 in which the inlet of said fluid trap is of smaller cross-section than the inlet to said sample siphon mix channel so that the siphon mix will always empty into said sample cuvette and the liquid in the fluid trap will not empty into said sample cuvette.

15. In an apparatus for analyzing whole blood an improved analyzer rotor comprising

a rotatable element having interconnected chambers and channels,

said channels and chambers comprising

a mixing chamber,

a diluent capillary channel having one end connecting to said mixing chamber,

a blood chamber,

a curved separating channel in communication with said blood chamber for separating red cells from the plasma of whole blood,

a plasma metering channel connecting said separating channel to said curved mixing chamber,

a diluent metering chamber connecting to the other end of said diluent capillary channel, and

means for rotating said rotatable element at varying speeds to effect movement of fluids through said channels and to mix said separated plasma with diluent.

16. The apparatus of claim 15 which includes a vented sample cuvette, a siphon mix channel connecting said sample cuvette to said mixing chamber, a control cuvette and channel means connecting said control cuvette to said diluent metering chamber.

17. The apparatus of claim 16 which includes a cover over said rotatable element, and openings through said cover to provide access to said blood and diluent metering chambers and vents for said cuvettes.

18. The apparatus of claim 16 which includes two or more sample cuvettes and two or more control cuvettes.

19. In an apparatus for separating liquids from solids, gas from liquids or two liquids of different densities an improved analyzer rotor comprising

a rotatable element mounted for rotation, having interconnecting chambers and channels disposed therein, said channels and chambers comprising

a sample chamber;

a curved separating channel having one end spaced radially farther from the center of rotation than the opposite end thereof;

a connecting channel extending from said sample chamber to said one end of said curved separating channel, and

means for rotating said rotatable element.

20. The apparatus of claim 19 in which said curved separating channel is curved having a configuration described by the equation

21. The apparatus of claim 19 which includes a vented cuvette and a channel connecting said vented cuvette to said curved separating channel.

22. In an apparatus comprising a rotatable element mounted for rotation having interconnecting chambers and channels disposed therein and means for rotating said element, an improved fluid metering means comprising

a fluid chamber

a capillary channel having an inlet end and an outlet end, said inlet end connecting to said fluid chamber for fluid filling of said capillary channel by capillary action

a vent on said capillary channel communicating to the atmosphere said capillary channel having a precise predetermined volume between said vent and said outlet end said inlet end and said outlet end being farther from the axis of rotation than said air vent

whereby, upon rotating said element, a precise amount of fluid may be dispensed from the outlet end of said capillary channel by centrifugal force.

23. In an analyzing apparatus comprising a rotatable element mounted for rotation about an axis, said element having interconnecting chambers and channels disposed therein and means for rotating said element, improved means for transferring fluid from one chamber to another comprising

a first chamber for supplying fluid

a second chamber for receiving fluid and

a capillary capillary channel having no vents, the ends of said channel connecting to said first and second chamber respectively, a portion of said capillary channel being closer to the axis of rotation than either said first or said second chambers

the point where said capillary channel connects to said first chamber being the point of that chamber which is at the greatest distance from said axis, said point also being closer to said axis than the point where the other end of said capillary channel connects it to said second chamber,

whereby upon rotation of said rotatable element fluid is transferred from said first to said second chamber by centrifugal force.

24. An analyzing apparatus comprising a rotatable element having a channel of curved configuration with a first end and a second end, the distance from the channel to the axis of rotation of said rotatable element becoming progressively shorter from said first to said second end, a cover for said channel, an access opening to the channel through said cover and means for rotating said rotatable element.

25. The apparatus of claim 24 in which said channel configuration is defined by the equation

26. In an analyzing apparatus comprising a rotatable element mounted for rotation about an axis, said element having interconnecting chambers and channels disposed therein and means for rotating said element, improved means for transferring fluid from one chamber to another comprising

a first chamber for supplying fluid

a second chamber for receiving fluid and

a capillary channel having no vents, the ends of said channel connecting to said first and second chamber respectively, a portion of said channel being closer to the axis of rotation than either said first or said second chambers

the point where said capillary channel connects to said first chamber being the point of that chamber which is at the greatest distance from said axis, said point also being closer to said axis than the point where the other end of said capillary channel connects it to said second chamber,

whereby upon rotation of said rotatable element fluid is transferred from said first to said second chamber by centrifugal force.