DEVICES AND METHODS FOR OVERLAYING BLOOD OR CELLULAR SUSPENSIONS

• US 20140356898A1
• Filed: 08/09/2012
• Published: 12/04/2014
• Est. Priority Date: 08/09/2011
• Status: Active Grant

• Current Assignee: Jae G.O. Kwon
• Original Assignee: Jae G.O. Kwon
• Inventors: Kwon, Jae Go
• Granted Patent: US 10,371,609 B2
• Time in Patent Office: Days
• US Class Current: 435/30
• CPC Class Codes: B01L 2200/026 Fluid interfacing between devices or objects, e.g. connectors, inlet details
• CPC Class Codes: B01L 2200/0642 Filling fluids into wells by specific techniques
• CPC Class Codes: B01L 2300/046 Function or devices integrated in the closure
• CPC Class Codes: B01L 2400/0457 passive flow or gravitation
• CPC Class Codes: B01L 2400/086 using baffles or other fixed flow obstructions
• CPC Class Codes: B01L 3/0293 for liquids
• CPC Class Codes: B01L 3/5021 Test tubes specially adapted for centrifugation purposes centrifuges B04B5/04
• CPC Class Codes: G01N 1/31 Apparatus therefor

Abstract

A device is described that overlays a first fluid, such as blood or a cellular suspension onto a base material, such as a density gradient. In some embodiments, the fluid layering device includes a cylindrical reservoir, a fluid barrier, a coupling extension, a plunger, and an exhaust vent. The fluid layering device can be coupled through its coupling extension to an open end of a container, such as a conical centrifuge tube, including the density gradient. Once attached, the plunger may be lowered to a position above the surface of the density gradient. A first fluid may flow from the reservoir into the conical tube across the plunger, so that a suitable overlay is formed without substantially disturbing a surface of the density gradient. The plunger may be buoyed upward by the first fluid during operation, providing a constant regulation of flow throughout overlaying, regardless of the care and skill of the user.

Claims

1. A fluid layering device configured to control a flow of fluid into an open-ended container, comprising:

a fluid reservoir, comprising

a housing defining an open-ended reservoir,

a coupling portion attached to the housing, and configured for inserting into an open-ended container for sealing engagement along an interior surface of the open-ended container, and

a central opening in the open-ended reservoir; and

a plunger, comprising

a shaft inserted through the central opening in the open-ended reservoir, and

a cylindrical cup attached to a lower end of the shaft.

2. The fluid layering device of claim 1, wherein the housing of the fluid reservoir comprises a longitudinally extending cylindrical side wall open at its proximal end and a fluid barrier disposed across a distal end of the cylindrical side wall, a proximal surface of the fluid barrier and an interior surface of the cylindrical side wall forming the open-ended reservoir.

3. The fluid layering device of claim 1, wherein the coupling portion of the fluid reservoir comprises a longitudinally extending sealing wall positioned to form a fluid-tight seal along the interior surface of the open-ended container.

4. The fluid layering device of claim 1, wherein the cup of the plunger further comprises a helical ridge configured to engage the interior surface of the open-ended container.

5. The fluid layering device of claim 4, wherein the coupling portion further comprises a helical channel configured to engage the helical ridge of the cup.

6. The fluid layering device of claim 1, wherein the cylindrical cup is hollow and the plunger is configured to be buoyantly raised by a fluid in the open-ended container.

7. The fluid layering device of claim 1, wherein the fluid reservoir further comprises an exhaust vent for venting gas from the open-ended container displaced by the addition of a fluid to the open-ended container.

8. The fluid layering device of claim 1, wherein the fluid reservoir further comprises a shoulder positioned to abut at least a portion of a rim of the open-ended container when the fluid layering device is inserted therein.

9. The fluid layering device of claim 1, wherein the shaft of the plunger is joined to the cylindrical cup via a sloped portion of the plunger.

10. The fluid layering device of claim 1, wherein a diameter of the shaft of the plunger is substantially smaller than a diameter of the central opening to allow a fluid to flow through the central opening around the shaft.

11. The fluid layering device of claim 1, wherein a diameter of the shaft of the plunger is similar to the diameter of the central opening, and wherein the fluid reservoir further comprises at least one drain port to allow a fluid to flow from the fluid reservoir into the open-ended container.

12. The fluid layering device of claim 1, wherein the fluid layering device is sterilized.

13. The fluid layering device of claim 1, wherein the fluid layering device is formed from material selected from the group consisting of:

plastics;

polymers;

resins;

glass;

ceramics;

metals; and

combinations thereof.

14. A method for controlling a flow of fluid into an open-ended container, comprising:

inserting a fluid layering device comprising a fluid reservoir and a plunger into a distal end of an open-ended container;

lowering the plunger to position a cup of the plunger at or above a surface of a base material; and

adding a first fluid into the fluid reservoir to flow into the distal end of the open-ended container and across an upper surface of the cup to be deposited over the base material without substantially disturbing the surface of the base material; and

wherein the first fluid buoyantly raises the plunger as the first fluid is deposited over the base material.

15. The method of claim 14, further comprising

exhausting from the distal end of the open-ended container gas displaced by the controlled flow of the first fluid.

16. The method of claim 14, wherein inserting the fluid layering device into the distal end of the open-ended container comprises inserting at least a proximal portion of the fluid layering device into the open end of the open-ended container.

17. The method of claim 14, wherein lowering the plunger further comprises disengaging a threaded portion of the plunger from a corresponding threaded portion of the fluid reservoir.

18. The method of claim 17, further comprising engaging the threaded portion of the plunger with the corresponding threaded portion of the fluid reservoir, and removing the fluid layering device from the open-ended container.

19. An apparatus comprising:

a rack configured to stabilize one or more containers to be used for fluid layering, wherein the rack is configured rest on a surface to support the one or more containers at angle relative to the surface.

20. A fluid layering device configured to control a flow of fluid into a container having an open top end and a closed bottom end, the device comprising a trap member that may be inserted into or integral with the open ended container, the trap member comprising:

an inlet chamber for receiving the flow of fluid from the open top end of the container and having an opening that allows fluid flow out of the inlet chamber towards the closed bottom end of the container,

a cap positioned at the opening configured to selectively allow and interrupt flow of fluid through the opening;

a reservoir defined by the a wall of the inlet chamber and a partial wall located below the inlet chamber; and

an exit chamber;

wherein the trap member is configured such that upon receiving a the flow of fluid at the first opening of the inlet,;

initially the cap opens in response to the fluid to allow fluid flow through opening and the exit chamber to the bottom of the container;

when the the fluid fills the container to a first level below the cap, the trap member directs at least a portion of the fluid flow to the reservoir; and

when the fluid fills the container to a second level above the cap, the cap interrupts the flow of fluid through the second opening.

21. A fluid layering device configured to control a flow of fluid into an open-ended container, comprising:

a trap member configured to ;

operate in a first state to allow a first layer of fluid to be added to a closed bottom portion of the open the container; and

operate in a second state to physically seal off a portion of the container containing at least a portion of the first layer in order to prevent mixing of the first layer with a subsequently added second layer of fluid.