Generating a Fluid Stream in a Microfluidic Device

Abstract

A fluid handling and delivery system useful in generating a fluid stream in the flow path of microfluidic device.

Claims

1-22. (canceled)

23. An apparatus, comprising: a plurality of receptacles each discretely defining an interior space adapted to maintain an amount of gas pressure of an amount of gas; at least one gas inlet element which delivers an amount of gas to said plurality of receptacles; at least one gas pressure adjustment element which regulates said amount of gas pressure maintained in each of said plurality of receptacles; a plurality of variable volume containers each having a flexible wall adapted to contain an amount fluid, said flexible wall having an interior surface which acts on said amount of fluid in response to said amount of gas pressure exerted on an exterior surface of said flexible wall; and a plurality of fluid outlet elements defining a plurality of flow paths correspondingly fluidically coupled to said amount of fluid contained in said plurality of variable volume containers, said plurality of flow paths adapted to correspondingly deliver a plurality of fluid streams generated in response to said amount of gas pressure exerted on said exterior surface of said flexible wall of said plurality of variable volume containers.

24. The apparatus of claim 23, wherein said at least one gas inlet comprises only one gas inlet which delivers said amount of gas pressure to said plurality of receptacles.

25. The apparatus of claim 23, wherein said at least one gas pressure adjustment element comprises only one gas pressure adjustment element which regulates said amount of gas pressure maintained in said plurality of receptacles.

26. The apparatus of claim 23, wherein said at least one gas inlet element comprises a plurality of gas inlet elements which correspondingly deliver said amount of gas pressure to each of said plurality of receptacles, and wherein said at least one gas pressure adjustment element comprises a plurality of gas pressure adjustment elements to correspondingly regulate said amount of gas pressure in each of said plurality of receptacles.

27. The apparatus of claim 25, wherein said amount of gas pressure maintained in each of said plurality of receptacles being substantially the same.

28. The apparatus of claim 26, wherein said plurality of gas pressure adjustment elements each adjustable to maintain a different said amount of gas pressure in each of said plurality of receptacles.

29. The apparatus of claim 23, wherein said amount of gas pressure occurs in a range of about 10 psi to about 200 psi.

30. The apparatus of claim 29, wherein said amount of gas pressure is selected from the group consisting of: about 15 psi to about 25 psi, about 20 psi to about 30 psi, about 25 psi to about 35 psi, 30 psi to about 40 psi, about 35 psi to about 45 psi, about 40 psi to about 50 psi, about 45 psi to about 55 psi, about 50 psi to about 60 psi, about 55 psi to about 65 psi, about 60 psi to about 70 psi, about 65 psi to about 75 psi, about 70 psi to about 80 psi, about 75 psi to about 85 psi, about 80 psi to about 90 psi, about 85 psi to about 95 psi, about 90 psi to about 100 psi, about 95 psi to about 105 psi, about 100 psi to about 110 psi, about 105 psi to about 115 psi, about 110 psi to about 120 psi, about 115 psi to about 125 psi, about 120 psi to about 130 psi, about 125 psi to about 135 psi, about 130 psi to about 140 psi, about 135 psi to about 145 psi, about 140 psi to about 150 psi, about 145 psi to about 155 psi, about 150 psi to about 160 psi, about 155 psi to about 165 psi, about 160 psi to about 170 psi, about 165 psi to about 175 psi, about 170 psi to about 180 psi, about 175 psi to about 185 psi, about 180 psi to about 190 psi, and about 185 psi to about 195 psi, and combinations thereof.

31. The apparatus of claim 23, wherein said plurality of fluid streams correspondingly have a plurality of fluid stream pressures, said plurality of fluid stream pressures being substantially the same.

32. The apparatus of claim 23, wherein said plurality of fluid streams correspondingly have a plurality of fluid stream pressures, said plurality of fluid stream pressures being substantially different.

33. The apparatus of claim 23, wherein said fluid stream pressure occurs in a range of about 10 psi to about 200 psi.

34. The apparatus of claim 33, wherein said fluid stream pressure is selected from the group consisting of: about 15 psi to about 25 psi, about 20 psi to about 30 psi, about 25 psi to about 35 psi, 30 psi to about 40 psi, about 35 psi to about 45 psi, about 40 psi to about 50 psi, about 45 psi to about 55 psi, about 50 psi to about 60 psi, about 55 psi to about 65 psi, about 60 psi to about 70 psi, about 65 psi to about 75 psi, about 70 psi to about 80 psi, about 75 psi to about 85 psi, about 80 psi to about 90 psi, about 85 psi to about 95 psi, about 90 psi to about 100 psi, about 95 psi to about 105 psi, about 100 psi to about 110 psi, about 105 psi to about 115 psi, about 110 psi to about 120 psi, about 115 psi to about 125 psi, about 120 psi to about 130 psi, about 125 psi to about 135 psi, about 130 psi to about 140 psi, about 135 psi to about 145 psi, about 140 psi to about 150 psi, about 145 psi to about 155 psi, about 150 psi to about 160 psi, about 155 psi to about 165 psi, about 160 psi to about 170 psi, about 165 psi to about 175 psi, about 170 psi to about 180 psi, about 175 psi to about 185 psi, about 180 psi to about 190 psi, and about 185 psi to about 195 psi, and combinations thereof.

35. The apparatus of claim 23, further comprising a fluid pressure generator fluidically coupled to one or more of said plurality of fluid outlet elements.

36. The apparatus of claim 23, wherein said flexible wall comprises a portion of said variable volume container.

37. The apparatus of claim 23, wherein said a flexible wall comprises at least two layers, wherein a first layer has a surface compatible with said amount of gas and a second layer has a surface compatible with said amount of fluid.

38. The apparatus of claim 23, further comprising one microfluidic device fluidically coupled to said plurality of fluid outlet elements.

39. The apparatus of claim 38, further comprising a plurality of microfluidic devices each fluidically coupled to one or more of said plurality of fluid outlet elements.

40. The apparatus of claim 39, further comprising a plurality of microfluidic devices each coupled to only one of said plurality of fluid outlet elements.

41. The apparatus of claim 40, wherein said microfluidic device or said plurality of microfluidic devices comprise a flow sort device.

42. The apparatus of claim 41, wherein said flow sort device comprises a flow cytometer.

Description

III. A BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG. 1A shows an embodiment of the invention which provides a pressure regulated variable volume container which delivers a fluid stream in response to an amount of gas acting on the exterior surface.

[0040] FIG. 1B shows a cross section through the flexible wall of an embodiment of the pressure regulated variable volume container.

[0041] FIG. 1C shows a cross section through the flexible wall of alternate embodiment of the pressure regulated variable volume container.

[0042] FIG. 1D shows a cross section through the flexible wall of second alternate embodiment of the pressure regulated variable volume container.

[0043] FIG. 1E shows a cross section through the flexible wall of third alternate embodiment of the pressure regulated variable volume container.

[0044] FIG. 2A shows a conventional sheath fluid tank for the delivery of sheath fluid(s) to a flow cytometer.

[0045] FIG. 2B shows an embodiment of the invention for the delivery of sheath fluid(s) to a flow cytometer in which a conventional sheath fluid tank is retrofitted to receive an amount of gas which acts upon the exterior surface of a variable volume container.

[0046] FIG. 2C shows an alternate embodiment of the invention for the delivery of sheath fluid(s) to a flow cytometer in which a conventional sheath fluid tank is retrofitted to receive an amount of gas which acts upon the exterior surface of a variable volume container.

[0047] FIG. 3A shows an embodiment of the invention in which a receptacle of substantially fixed configuration receives an amount of gas which acts upon the exterior surface of a variable volume container.

[0048] FIG. 3B shows an alternate embodiment of the invention in which a receptacle of substantially fixed configuration receives an amount of gas which acts upon the exterior surface of a variable volume container.

[0049] FIG. 4A shows an embodiment of the invention in which a plurality of receptacles each receive an amount of gas which acts upon the exterior surface of a variable volume container to generate a plurality of fluid streams.

[0050] FIG. 4B shows an alternate embodiment of the invention in which a plurality of receptacles each receive an amount of gas which acts upon the exterior surface of a variable volume container to generate a plurality of fluid streams.

[0051] FIG. 5 shows a flow cytometer embodiment of the invention in which a fluid stream can be generated in the flow path of the flow cytometer from a variable volume container acted upon by an amount of gas.

[0052] FIG. 6 shows a bivariate plot of sperm cells entrained in a fluid stream generated in accordance with the invention differentiated into X-chromosome bearing and Y-chromosome bearing populations.

[0053] FIG. 7 shows an embodiment of the invention in which a plurality of variable volume containers each containing an amount of fluid are configured into a sheet of columns and rows.

[0054] FIG. 8 illustrates a plurality of flow paths operable with the embodiment of the invention shown by FIG. 7.

IV. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0055] Generally, an amount of fluid located within a variable volume container having a flexible wall which acts upon the amount of fluid in response to gas pressure exerted on the exterior surface to generate a fluid stream in the flow path of a conduit.

[0056] Now referring primarily to FIG. 1, an embodiment of the invention can provide a variable volume container (1) having a flexible wall (2) which acts on an amount of fluid (3) within the variable volume container (1) in response to an amount of pressure (4) exerted on the exterior surface (5) of the flexible wall (2) by an amount of gas (6). The amount of pressure (4) exerted on the exterior surface (5) of flexible wall (2) continuously adjusts the volume of the variable volume container (1) to act on the amount of fluid (3) to generate a fluid stream (7) (whether of continuous flow or of discontinuous flow) in the flow path of a conduit (8). As to certain embodiments of the invention the variable volume container (1) can in part be of substantially rigid configuration and in part a flexible wall (2). That portion of the variable volume container (1) which provides the flexible wall (2) can act on the amount of fluid (3) within the variable volume container (1) in response to the amount of pressure (4) exerted on the exterior surface (5) of the flexible wall by the amount of gas (6) to generate a fluid stream (7).

[0057] The fluid (3) within the variable volume container (1) broadly encompasses without limitation any fluid, liquid, composition, mixture, phase, product, or other material flowable in the flow path of the conduit (8) by continuous adjustment of the volume of the variable volume container (1) in response to the amount of pressure (4) exerted on exterior surface (5) of the flexible wall (2). The numerous and varied fluids flowable in the flow path of the conduit (8) (the flow path of the conduit includes numerous and varied configurations corresponding to the broad range of applications for the invention and without limitation includes microfluidic flow paths or conduits which typically have an internal diameter of about one millimeter or less) includes without limitation: water, a solvent, a solution, a buffered solution, a liquid chromatography solution, a fluid in which biological particles can be entrained, a fluid in which non-biological particles can be entrained, a fluid in which cells can be analyzed, a fluid in which sperm cells can be analyzed, a fluid in which sperm cells can be separated into Y-chromosome bearing and X-chromosome bearing populations, a flow cytometry sheath fluid, a flow cytometry sheath fluid in which non-biological particles can be entrained, a flow cytometry sheath fluid in which biological particles can be entrained, a flow cytometry sheath fluid in which cells are entrained, a flow cytometry sheath fluid in which spermatozoa can be entrained, a flow cytometry sheath fluid in which stained spermatozoa can be entrained, paint, pesticides, pastes, adhesives, organic solvents, pesticides, food products, beverages, and various permutations and combinations thereof.

[0058] Now referring primarily to FIG. 1B, the variable volume container (1) can provide a flexible wall (2) on which the amount of gas (6) exerts an amount pressure (4). The flexible wall (2) can comprise a layer of material (9) which has sufficient flexibility to adjust volume of the variable volume container (1) in response to the amount of pressure (4) exerted by the amount of gas (6) on the exterior surface (5). The layer of material (9) can be selected to provide an interior surface (10) compatible with the fluid (3) contained within the variable volume container (1) and to provide an exterior surface (5) compatible with the amount gas (6) which exerts the amount of pressure (4) thereon. With respect to certain embodiments of the invention, the layer of the material can further be selected to prevent or minimize the transfer of materials leachable or transferable from the layer of material (9) to the fluid (3) held by the variable volume container (1). The layer of material (9) can further be selected to prevent or minimize the transfer the amount of gas (6) through the layer of material (9) to the fluid held by the variable volume container (1). Without limiting the numerous and varied materials that can be used in accordance with the invention, preferred embodiments of the invention can utilize a layer of material (9) such as a polypropylene, a polyethylene, a nylon, a fluorocarbon, a styrene, a polycarbonate, a metal foil, a laminated paper, a biodegradable polymer, a waxed paper, or bonded layers thereof in various permutations and combinations. The layer of material (9) can include a coat of material, such as an oxygen barrier, a water barrier, alternate layers of a surface filling polymer and a ceramic (for example Barix), or the like.

[0059] Now referring primarily to FIG. 1C, as to other embodiments of the invention the flexible wall (2) can comprise two layers of material. The first layer (11) which establishes the exterior surface (5) compatible to the amount of gas (6) which exerts a pressure (4) on the flexible wall (2) and a second layer (12) providing an interior surface (10) compatible with the fluid (3) within the variable volume container (1). The first layer (11) can be selected from materials such as a polypropylene, a polyethylene, a fluorocarbon, a styrene, a polycarbonate, a Mylar film, an oxygen barrier, a water barrier, or the like. The second layer (12) can be selected from the same or a different material then the first layer (11) such as a polypropylene, a polyethylene, a fluorocarbon, a styrene, a polycarbonate, a water barrier, or oxygen barrier (for example Barix), or the like. Either or both of the first layer (11) or the second layer (12) can be further include a reinforcement element (48) such as individual fibers, threads, strands, a net, web, or the like, which can be made of a reinforcement material such as a nylon, a cotton, a carbon fiber, a metal strand, a plastic strand, or the like.

[0060] As to certain embodiments of the invention, the first layer (11) and the second layer (12) of the flexible wall (2) can slidely engage, while as to other embodiments of the invention the first layer (11) and the second layer (12) can be fixedly engaged. Fixed engagement between the first layer (11) and the second layer (12) can be generated by the use of an adhesive layer (13), or other type of layer, or other process which induces a surface of the first layer (11) and a surface of the second layer (12) to adhere to each other.

[0061] Now referring primarily to FIG. 1D, as to other particular embodiments of the invention, a gas collection element (14) can be interposed between the first layer (11) and the second layer (12). As to these embodiments of the invention, the amount of gas (6) which exerts an amount of pressure (4) on the exterior surface (5) of the variable volume container (1) collects in the gas collection element (14) and exerts an amount of pressure (4) on the second layer (12) which acts on the liquid (3) contained within to generate the fluid stream (7). The first layer (11) acts to adjust the volume or pressure (or both) of the amount of gas (6) within the gas collection element (14) to the necessary or desired amount. As to these embodiments of the invention, in which the first layer (11) does not have to function as part of a flexible wall (2) of the variable volume container (1), the first layer (11) can have a substantially fixed configuration formed from a material such as a plastic, a fiberglass, a glass, a metal, a steel, a polycarbonate, an acrylic, a polypropylene, a vinyl, a fluorocarbon, a carbon fiber, or the like.

[0062] Now referring primarily to FIG. 1E, other embodiments of the invention can further include a flexible wall (2) having at least one intermediate layer (15) located between the first layer (11) and the second layer (12). The at least one intermediate layer (15) be can be selected from a material such as a polypropylene, a polyethylene, a fluorocarbon, a styrene, a polycarbonate, a Mylar film, a ceramic layer, an oxygen barrier (or other gas), a water barrier, or the like. Additional embodiments of the invention can further provide the gas collection element (14) (similar to FIG. 1D) interposed between the first layer (11) and the at least one intermediate layer (15), or as to other particular embodiments of the invention the gas collection element (14) (similar to FIG. 1D) can be interposed between the second layer (12) and the at least one intermediate layer (15). Where the gas collection element (14) is interposed between the first layer (11) and the at least one intermediate layer (15), the first layer (11) can be of substantially fixed configuration as above-described. In those embodiments of the invention in which the gas collection element (14) is interposed between the second layer (12) and the at least one intermediate layer (15), either of the first layer (11) or the at least one intermediate layer (15), or both, can have a substantially fixed configuration, while the second layer (12) provides sufficient flexibility to allow the variable volume container (1) to continuously adjust volume in response to the amount of pressure (4) exerted by the amount of gas (6) on the flexible wall (2). As to those embodiments of the invention, in which the liquid (3) engages the interior surface (10) of the second layer (12) and the amount of gas (6) exerts an amount of pressure (4) on the exterior surface (5) of the first layer (11), then the first layer (11), the intermediate layer (15) and the second layer (12) can have sufficient flexibility to allow variable adjustable volume of the container (1) whether the surfaces of the layers have slidely or fixed engagement.

[0063] The amount of gas (6) which exerts an amount of pressure (4) on the exterior surface (5) of the flexible wall (2) to provide a continuously adjustable variable volume container (1) to act on the fluid (3) contained within can be any type or kind of gas (6) compatible with the exterior surface (5) of the flexible wall (2) on which it acts, such as, an atmosphere, a mixture of gases, a mixture of gases having selected partial pressures, a purified gas, a filtered gas, a conditioned gas, or the like. As to alternate embodiments of the invention, the amount of gas (6) can be replaced with an amount of flowable material capable of acting upon the exterior surface (5) of the flexible wall (2) to adjust the volume of the container (1), such as water, oil, or a solution.

[0064] With respect to certain embodiments of the invention, the gas (6) can exert an amount of pressure (4) on the exterior surface (5) of the flexible wall (2) of between 1 pound per square inch (psi) to about 500 pounds per square inch (psi). As to other embodiments of the invention utilized for flow cytometry applications, the amount of gas (6) can exert a pressure on the exterior surface (5) of the flexible wall (2) of between about 10 psi and about 200 psi. Alternately, the amount of gas (6) whether within the gas collection element (14), or otherwise, can be adjusted to generate a sufficient amount of pressure (4) on the exterior surface (5) of the flexible wall (2) of the variable volume container (1) to generate a fluid stream (7) within the flow path of a conduit (8) of a microfluidic device (16) having a fluid pressure of between 10 psi and about 200 psi, or a fluid pressure sufficient to generate a fluid stream (7) within the flow path of the conduit (8) having a velocity sufficient to entrain particles for a particular type or kind of application, analysis, differentiation, or separation.

[0065] Again referring primarily to FIG. 1A, particular embodiments of the invention can further include fluid pressure generator (17), such as a peristaltic pump, piston pump, or the like to generate sufficient pressure for certain microfluidic applications, or other applications, in the range of between about 100 psi and about 5000 psi. One illustrative embodiment of the invention, provides a microfluidic device (16) configured as a high pressure liquid chromatograph (HPLC) having a fluid pressure generator (17) which increases fluid pressure within the conduit (8) to between about 100 psi and about 3000 psi for applications such as normal phase or reverse phase liquid chromatography.

[0066] Now referring primarily to FIG. 2A, a conventional substantially cylindrical sheath fluid tank (18) (or other configuration of sheath fluid tank) can have an aperture element (19). The aperture element (19) of the sheath fluid tank (18) can be configured to mate with a removably sealable closure (20) which can further include a closure securement element (21) to secure the removably sealable closure (20). Alternate embodiments of the closure securement element (21) can include, as examples, mated spiral threads on the removable sealable closure (20) and the sheath fluid tank (18), spiral threaded rods connected to the sheath fluid tank which mate with spirally threaded hardware which operationally apply pressure to the removably sealable closure (20), straps, catches, or the like.

[0067] A gas inlet element (22) allows delivery of an amount of gas (6) (various types and kinds of gas(es) as above-described) to the interior of the sheath fluid tank (18). In conventional applications, an amount of fluid (3) is contained by the sheath fluid tank (18) and the amount of gas (6) delivered to the interior of the sheath fluid tank (18) exerts an amount of pressure (4) on the surface of the fluid (3). A portion of the fluid (3) under pressure flows through the fluid outlet element (23) to be delivered as a fluid stream (7) in the flow path of a flow cytometer (24) (or other microfluidic device). A pressure adjustment element (25) (such as a pressure relief valve) can allow for adjustment of the amount of pressure within the sheath fluid tank (18).

[0068] Now referring primarily to FIG. 2B, a conventional sheath fluid tank (18) (or similar fluid tank) can be adapted to operate in accordance with the invention. A variable volume container (1) having a flexible wall (2) can contain an amount of fluid (3) (sheath fluid for flow cytometry applications). The variable volume container (1) containing the fluid (3) can be located inside of the conventional sheath fluid tank (18) by transfer through the aperture element (19). A conduit (8) provides a flow path between the variable volume container (1) and the fluid outlet element (23). A coupler element (26) may be required to connect the conduit (8) to the fluid outlet element (23) of the sheath fluid tank (18). The coupler element can in certain instances comprise mated spirally threaded hardware which operates to compress a ferrule against a seat to seal the flow path within the conduit (8) from leaking fluid. Naturally, a variety of hardware can be used as the coupler element (26) to provide a continuous flow path to the fluid outlet element (23).

[0069] Now referring primarily to FIG. 2C, as to certain embodiments of the invention the variable volume container (1) can be enclosed by a second layer (12) of substantially fixed configuration as discussed above formed from a material such as a plastic, a fiberglass, a glass, a metal, a steel, a polycarbonate, an acrylic, a polypropylene, a vinyl, a fluorocarbon, a carbon fiber, a paperboard, a cardboard, or the like. The second layer can be sufficiently perforated or permeable to an amount of gas (6) to allow an amount of pressure (4) to be exerted on the exterior surface (5) of the flexible wall (2) to act upon the amount of liquid (3) or sheath fluid contained within to generate a fluid stream (7) within the flow path of the conduit (8).

[0070] Now referring primarily to FIG. 3A, certain embodiments of the invention can provide a receptacle (27) of substantially fixed configuration (rectangular as shown by FIG. 3A or otherwise as desired) in which one or more variable volume container(s) (1) having a flexible wall (2) can be located. The receptacle (27) may be mounted on a base (28) which orients the receptacle (27) relative to a support surface (29) (for example, angled as shown by FIG. 3A or substantially perpendicular to the support surface (29) as shown by FIG. 3B) which can facilitate flow of the fluid (3) within the variable volume container (1) toward the conduit (8) which communicates with the fluid outlet element (23). The receptacle (27) of substantially fixed configuration can be made from a material such as a plastic, a fiberglass, a glass, a metal, a steel, a polycarbonate, an acrylic, a polypropylene, a vinyl, a fluorocarbon, a carbon fiber, or the like. A portion or the entirety of the receptacle (27) can be made from a material which allows visual observation of the variable volume container (1) and the fluid (3) within the variable volume container (1). The receptacle (27) can further include a gas inlet element (22) through which an amount of gas (6) can be introduced into the gas collection element (14) between the interior surface of the receptacle (27) and the exterior surface (5) of the variable volume container (1). A pressure adjustment element (25) can be further included to maintain the necessary or desired amount of gas pressure (4) exerted on the exterior surface (5) of the variable volume container (1).

[0071] Now referring primarily to FIG. 4A, certain embodiments of the invention can include a plurality of receptacles (27), individually discrete or as a single integral piece (as shown by FIGS. 4A and 4B) providing a corresponding plurality of gas collection elements (14). FIG. 4A illustrates that each of the plurality of gas collection elements (14) can provide independent gas inlet elements (22), fluid outlet elements (23), and pressure adjustment elements (25) to allow each of the plurality of receptacle (27) to be utilized independent of the other receptacles (27). In this configuration of the invention, an amount of gas (6) can be delivered to each gas collection element (14) to establish an amount of pressure (4) on the exterior surface (5) of the flexible wall (2) of the variable volume container (1) located inside the individual receptacle (27). Accordingly, an amount of the fluid (3) contained in each of the variable volume containers (1) can be delivered to the fluid outlet element (23) from each receptacle (27). The fluid flow rate from each variable volume container (1) can be adjusted to be substantially the same or variably adjusted between receptacles (27).

[0072] Now referring primarily to FIG. 4B, alternate embodiments of the invention can provide a single gas inlet element (22) to deliver an amount of gas (6) to all the gas collection elements (14) to establish a substantially similar amount of gas pressure (4) on the exterior surface (5) of the flexible wall (2) of each of the plurality of variable volume containers (1) in the corresponding each of the plurality of receptacles (27) which can be adjusted by a single pressure adjustment element (25). Each receptacle can further provide a fluid outlet element (23) through which a fluid stream (7) can flow to the flow path of a microfluidic device (16) (similar to that shown in FIG. 1A).

[0073] Now referring primarily to FIG. 5, a generic microfluidics device in accordance with the invention is illustrated. An amount of gas (6) can be delivered with a pressure differential generator (30) such as a tank of pressurized gas, a gas compressor, or the like, to one or more gas inlet elements (22) of the receptacle(s) (27) through a gas transfer conduit (31). A pressure regulator (32) can be further included to regulate the pressure of the amount of gas (6) in the gas transfer conduit (31). The amount of gas (6) transfers from the gas inlet element (22) to a gas collection element (14) inside the receptacle (27) which can have a substantially fixed configuration as shown, or alternately described herein. At least one variable volume container (1) as above-described can be located inside the receptacle (27).

[0074] The amount of gas (6) within the gas collection element (14) acts upon the exterior surface (5) of the at least one variable volume container (1) located within the receptacle (27) to generate a fluid stream (7) at the fluid outlet element (25) which can be transferred within one or a plurality of conduits (8). The conduits (8) can have substantially the same internal diameter or varying internal diameters. The conduit (8) can further include a fluid conditioning element (33) such as a fluid filter, a gas scrubber, or a fluid pressure regulator, fluid pressure generator, such as a pump, or various permutations or combinations thereof. The conduit (8) can be connected to the flow path of a microfluidics device (24), such as a flow cytometer as shown in FIG. 5, or other microfluidic device, such as a fluid distribution device which transfers liquid(s) to and between locations on a liquid containment element such as plates having a plurality of wells, the surface of slides, cuvettes, channels, or other containment features.

[0075] As to the flow cytometer embodiment of the invention shown in FIG. 5, the fluid stream (7) can entrain particles (33) (as described above) delivered from a particle source (34). The fluid stream (7) having particles (33) entrained can be oscillated by a nozzle (35) to generate a plurality of droplets (36) below the nozzle (35). Each of the plurality of droplets (36) can entrain an individual particle (33). An illumination source (37), such as a laser, can emit a beam of light (38), or a plurality of beams of light can be generated by utilizing a beam splitting element (39) (or by utilizing a plurality of illumination sources (37)), which can be focused through an optical element (40) incident upon the particle (33) entrained in the fluid stream (7) below the nozzle (35), either as a single beam of light or a plurality of beams of light, whether at the same or different wave lengths. As to some embodiments of the invention, characteristics of the beam of light (38) can be altered by incidence upon the particle (33) within the fluid stream (7), and as to other embodiments of the invention the particle (or ligands, fluorescent materials, or the like, attached to the particle) can generate an emission (41). The beam(s) of light having altered characteristics or the emission (41) can be received by a single or a plurality of detectors (42) which can generate a signal for analysis to differentiate the particles (33) entrained in the droplets (36) based upon one or a plurality of particle characteristics. The differentiated particles can be separated based upon the presence or absence of one or a plurality of particle characteristics into individual collection elements (43). The separation device (44) can include a droplet charge generator (45) which induces a positive or negative charge in each droplet (36) and a droplet deflector (46) which acts upon the charged droplets to establish a trajectory to the proper collection element (43).

[0076] Now referring primarily to FIG. 6, a bivariate plot generated during the flow sort of spermatozoa into X-chromosome bearing and Y-chromosome bearing populations in accordance with the invention is shown. The bivariate plot shows that a mixture of X-chromosome bearing sperm cells and Y-chromosome bearing sperm cells can be resolved into first X-chromosome bearing population (49) and second Y-chromosome bearing population (50). Provision of the bivariate plot is not intended to be limiting with respect to the numerous and varied applications of the invention. Rather, the bivariate plot is intended to be illustrative of the broad range of applications in which the invention can be utilized.

[0077] Now referring primarily to FIG. 7, certain embodiments of the invention can provide a plurality of variable volume containers (1) configured as a single integral piece formatted in columns and rows, or otherwise as necessary or desired. A plurality of receptacles (27) configured as a single integral piece formatted in columns and rows can receive the plurality of variable volume containers (1). A releasably sealable closure (20) can be configured to isolate each of the plurality of variable volume containers (1). An amount of gas (6) can be delivered through a gas inlet element (22a) (22b) (two embodiments shown) to the gas collection element (14) within each separate receptacle (27), whether to a single receptacle of the plurality of receptacles or to a plurality of receptacles substantially simultaneously. The amount of gas (6) exerts an amount of pressure (4) on the flexible wall(s) (2) of the individual variable volume containers (1) to generate a fluid stream in one or a plurality of conduits (8) which communicate with each receptacle (27).

[0078] Now referring primarily to FIG. 8, the conduit (8) which fluidicly communicates with each receptacle (27) can comprise a microfluidic conduit (internal diameter of one millimeter or less) such as a plastic tube, or as shown in FIG. 8 can also comprise a relief element (44) in the surface of a single or a plurality of fluid delivery bodies (45) which provides a flow path for the fluid stream (7). The fluid delivery bodies (45) can be releasably sealable and interchangeable to provide a number of different flow paths. In the embodiment shown, the flow path established by the releasably sealable fluid delivery bodies can deliver the fluid (3) from a plurality of variable volume containers (1) to a plate (46) having a plurality of wells (47).

V. EXAMPLES

Example 1

[0079] Now referring to FIG. 8, which shows a bivariate plot generated from the analysis of fluorochrome stained sperm cells differentiated based upon the presence of an X-chromosome or a Y-chromosome utilizing a DakoCytomation, Inc., MoFlo flow cytometer in accordance with the invention. A conventional sheath fluid tank was retrofitted with a variable volume container in accordance with the invention containing about 5 liters of sterile sheath fluid. The sheath fluid was maintained at about 20 C. during use. An amount of gas was delivered to the sealed sheath fluid tank to exert an amount of gas pressure on the exterior surface of the variable volume container resulting in the generation of a fluid stream within the flow path of a DakoCytomation, Inc., MoFlo flow cytometer. The flow cytometer was then otherwise operated in accordance with the standard operation procedures provided by DakoCytomation, Inc. for a period of about 8 hours to analyze and sort a mixture of sperm cells to generate a viable population of X-chromosome bearing spermatozoa and viable population of Y-chromosome bearing spermatozoa. X-chromosome bearing and Y-chromosome bearing populations enriched were established in discrete collection containers.

Example 2

[0080] Similarly, a flow cytometer sorting human sperm in accordance with the invention can provide X-chromosome bearing and Y-chromosome bearing populations for the purpose of sex selected artificial insemination. Human sperm cells sufficient for artificial insemination of a human female can be flow sorted in approximately 2 hours from male human ejaculate. The enriched X-chromosome bearing or Y-chromosome bearing sperm cell populations are typically over 80% pure. Clinical procedures may require that after each sample is sorted, the sorting fluidic channels are washed with an acid wash, a base wash, a disinfectant wash, and then a water wash. The instant invention can be used to deliver four different sterile fluids to the flow cytometer, and allows computer automated cleaning steps to be performed between patients. During the automated wash procedure, the physician may perform the artificial insemination procedure.

Example 3

[0081] In accordance with the invention, a plurality of different microfluidic devices can be operating 24 hours per day. The variable volume containers can be located in common receptacle pressured at about 1.6 atmospheres. Each microfluidic device can be served with one or more conduits from the variable volume containers which communicate with the conventional hardware of the microfluidic device.

[0082] As can be easily understood from the foregoing, the basic concepts of the present invention may be embodied in a variety of ways. The invention involves numerous and varied embodiments of a continuously variable volume container for fluid delivery and methods of making and using such continuously variable volume container.

[0083] As such, the particular embodiments or elements of the invention disclosed by the description or shown in the figures accompanying this application are not intended to be limiting, but rather exemplary of the numerous and varied embodiments generically encompassed by the invention or equivalents encompassed with respect to any particular element thereof. In addition, the specific description of a single embodiment or element of the invention may not explicitly describe all embodiments or elements possible; many alternatives are implicitly disclosed by the description and figures.

[0084] It should be understood that each element of an apparatus or each step of a method may be described by an apparatus term or method term. Such terms can be substituted where desired to make explicit the implicitly broad coverage to which this invention is entitled. As but one example, it should be understood that all steps of a method may be disclosed as an action, a means for taking that action, or as an element which causes that action. Similarly, each element of an apparatus may be disclosed as the physical element or the action which that physical element facilitates. As but one example, the disclosure of an adjustable volume should be understood to encompass disclosure of the act of adjusting volumewhether explicitly discussed or notand, conversely, were there effectively disclosure of the act of adjusting volume, such a disclosure should be understood to encompass disclosure of an adjustable volume and even a means for adjusting volume. Such alternative terms for each element or step are to be understood to be explicitly included in the description.

[0085] In addition, as to each term used it should be understood that unless its utilization in this application is inconsistent with such interpretation, common dictionary definitions should be understood to included in the description for each term as contained in the Random House Webster's Unabridged Dictionary, second edition, each definition hereby incorporated by reference.

[0086] Thus, the applicant(s) should be understood to claim at least: i) each of the fluid delivery devices herein disclosed and described, ii) the related methods disclosed and described, iii) similar, equivalent, and even implicit variations of each of these devices and methods, iv) those alternative embodiments which accomplish each of the functions shown, disclosed, or described, v) those alternative designs and methods which accomplish each of the functions shown as are implicit to accomplish that which is disclosed and described, vi) each feature, component, and step shown as separate and independent inventions, vii) the applications enhanced by the various systems or components disclosed, viii) the resulting products produced by such systems or components, ix) methods and apparatuses substantially as described hereinbefore and with reference to any of the accompanying examples, x) the various combinations and permutations of each of the previous elements disclosed.

[0087] The claims set forth in this specification are hereby incorporated by reference as part of this description of the invention, and the applicant expressly reserves the right to use all of or a portion of such incorporated content of such claims as additional description to support any of or all of the claims or any element or component thereof, and the applicant further expressly reserves the right to move any portion of or all of the incorporated content of such claims or any element or component thereof from the description into the claims or vice-versa as necessary to define the matter for which protection is sought by this application or by any subsequent continuation, division, or continuation-in-part application thereof, or to obtain any benefit of, reduction in fees pursuant to, or to comply with the patent laws, rules, or regulations of any country or treaty, and such content incorporated by reference shall survive during the entire pendency of this application including any subsequent continuation, division, or continuation-in-part application thereof or any reissue or extension thereon.

[0088] The claims set forth below are intended describe the metes and bounds of a limited number of the preferred embodiments of the invention and are not to be construed as the broadest embodiment of the invention or a complete listing of embodiments of the invention that may be claimed. The applicant does not waive any right to develop further claims based upon the description set forth above as a part of any continuation, division, or continuation-in-part, or similar application.