FLOW CYTOMETER SYSTEM WITH UNCLOGGING FEATURE

• US 20100319786A1
• Filed: 08/16/2010
• Published: 12/23/2010
• Est. Priority Date: 03/08/2006
• Status: Active Grant

• Current Assignee: Accuri Cytometers, Inc. (Becton Dickinson & Co)
• Original Assignee: Accuri Cytometers, Inc. (Becton Dickinson & Co)
• Inventors: Rich, Collin A., Bair, Nathaniel C.
• Granted Patent: US 8,262,990 B2
• Time in Patent Office: Days
• US Class Current: 137/15.01
• CPC Class Codes: F04B 2201/1201 Rotational speed of the axis
• CPC Class Codes: F04B 2205/09 Flow through the pump
• CPC Class Codes: F04B 23/04 Combinations of two or more pumps
• CPC Class Codes: F04B 43/0081 systems, control, safety measures
• CPC Class Codes: F04B 43/12 having peristaltic action
• CPC Class Codes: G01N 15/1404 Handling flow, e.g. hydrodynamic focusing
• CPC Class Codes: G01N 2015/1413 Hydrodynamic focussing
• CPC Class Codes: G05D 7/0682 using a plurality of flow sources
• CPC Class Codes: Y10T 137/0352 Controlled by pressure
• CPC Class Codes: Y10T 137/0379 By fluid pressure
• CPC Class Codes: Y10T 137/0402 Cleaning, repairing, or assembling
• CPC Class Codes: Y10T 137/85986 Pumped fluid control
• CPC Class Codes: Y10T 436/115831 Condition or time responsive
• CPC Class Codes: Y10T 436/117497 with a continuously flowing sample or carrier stream

Abstract

The fluidic system with an unclogging feature of the preferred embodiment includes a flow channel, a sheath pump to pump sheath fluid from a sheath container into an interrogation zone, and a waste pump to pump waste fluid from the interrogation zone into a waste container. The sheath pump and/or the waste pump draw sample fluid from a sample container into the interrogation zone. The fluidic system also includes a controller to adjust the flow rate of the sample fluid from the sample container into the interrogation zone. The pump and controller cooperate to propagate a pulsation through the flow channel from the pump if the flow channel is clogged. The fluidic system is preferably incorporated into a flow cytometer with a flow cell that includes the interrogation zone.

Claims

1. A fluidic system for unclogging a flow channel of a flow cytometer including an interrogation zone and a system fluid with a pressure and a flow rate, the fluidic system comprising:

a sheath pump adapted to pump the system fluid from a sheath container into the interrogation zone;

a waste pump adapted to pump the system fluid from the interrogation zone into a waste container;

a motor with motor controls coupled to at least one of the pumps of the fluidic system;

a clog detector that automatically detects clogs in the flow channel; and

a controller connected to the motor and configured to vary the pumping rate of at least one of the pumps of the fluidic system to vary the flow rate of the system fluid and induce a commensurate change in the pressure of the system fluid to create pulsations within the system fluid that unclog the flow channel of the flow cytometer.

2. The fluidic system of claim 1, wherein the controller is configured to create pulsations that have a pulsation pressure that is at least five times greater than the pressure of the system fluid.

3. The fluidic system of claim 2, wherein the pulsations have a time interval of separation equal to or less than one second.

4. The fluidic system of claim 1, including a pressure sensor that automatically detects clogs in the flow channel by measuring a pressure of the system fluid.

5. The fluidic system of claim 4, further comprising a drawtube that conveys a sample fluid from a sample container into the interrogation zone, wherein the pressure sensor measures a pressure differential between the top of the drawtube and the bottom of the drawtube.

6. The fluidic system of claim 1, further comprising a flow meter that automatically detects clogs in the flow channel by measuring the flow rate of a sample fluid from a sample container into the interrogation zone.

7. The fluidic system of claim 1, wherein the pulsations unclog the flow channel of a substance inserted in the flow channel.

8. The fluidic system of claim 7, wherein the substance is at least one of sample debris and clustered cells.

9. The fluidic system of claim 7, wherein the substance is in a portion of the flow channel before interrogation in the interrogation zone.

10. The fluidic system of claim 1, wherein the motor includes a variable drive ratio device and the sheath pump and the waste pump are driven by the motor, wherein the sheath pump and the waste pump may be operated at different pump speeds, wherein the controller is connected to the variable drive ratio device such that the controller can vary the pumping rates of the sheath pump and the waste pump.

11. The fluidic system of claim 1, further comprising at least one valve adapted to facilitate the control of the system fluid.

12. The fluidic system of claim 11, wherein the valve is a by-pass valve located near at least one of the pumps of the system, wherein the controller is operatively connected to the by-pass valve and is configured to divert a variable amount of the system fluid through the by-pass valve.

13. The fluidic system of claim 11, wherein the valve is a restrictive valve located near at least one of the pumps of the system, wherein the controller is operatively connected to the restrictive valve and is adapted to open and close the restrictive valve.

14. The fluidic system of claim 1, further comprising a second motor with second motor controls, wherein the sheath pump is driven by the first motor and the waste pump is driven by the second motor and wherein the sheath pump and the waste pump may be operated at different pump speeds, and wherein the controller is connected to at least one of the first motor controls and second motor controls such that the controller can vary the pumping rates of the sheath pump and the waste pump.

15. The fluidic system of claim 1, wherein the controller is further configured to terminate the creation of pulsations within the system fluid automatically once a pre-defined threshold for a parameter has been reached, wherein the pre-defined parameter is selected from the group consisting of a time interval, an energy output, a full return of flow, a partial return of flow, a break up of the clog, and combinations thereof.

16. The fluidic system of claim 1, wherein the controller is further configured to create pulsations in anticipation of a clog in the flow channel.

17. A method for unclogging a flow cytometer with a flow channel, an interrogation zone and a fluidic system including a sheath pump, a waste pump, and a system fluid, the method comprising:

controlling the fluidic system including the cooperative steps;

pumping system fluid from a sheath container into the interrogation zone with the sheath pump,

pumping system fluid from the interrogation zone into a waste container with the waste pump;

detecting a clog in the flow channel; and

propagating pulsations through the fluidic system by adjusting the flow rate of the system fluid, wherein adjusting the flow rate of the system fluid includes controlling the pump speed of at least one of the sheath pump and waste pump.

18. The method of claim 17, wherein the pulsations have an induced pressure at least five times greater than a baseline pressure of the fluidic system.

19. The method of claim 17, wherein detecting a clog in the flow channel includes automatically detecting a clog in the flow channel.

20. The method of claim 19, wherein detecting a clog in the flow channel includes measuring a pressure differential.

21. The method of claim 20, wherein detecting a pressure differential includes measuring a pressure differential between the top and bottom of a drawtube that conveys sample fluid from a sample container into the interrogation zone.

22. The method of claim 19, wherein detecting a clog in the flow channel includes detecting a change in flow rate of system fluid.

23. The method of claim 22, wherein detecting a change in flow rate of system fluid includes detecting a change in flow rate of a sample fluid from a sample container into the interrogation zone.

24. The method of claim 17, wherein detecting a clog in the flow channel includes detecting at least one of sample debris and clustered cells.

25. The method of claim 17, wherein detecting a clog in the flow channel includes detecting a substance inserted into the flow channel before interrogation in the interrogation zone.

26. The method of claim 17, wherein the step of propagating pulsations includes maintaining a consistent flow rate of at least one of the sheath pump and waste pump.