WO2008106409A1

WO2008106409A1 - Alternating connection rotating seal apparatus

Info

Publication number: WO2008106409A1
Application number: PCT/US2008/054921
Authority: WO
Inventors: Lucas Fornace; Robert K. Shanahan; Jonathan Costabile
Original assignee: Cytory Therapeutics, Inc.
Priority date: 2007-02-26
Filing date: 2008-02-25
Publication date: 2008-09-04

Abstract

Provided herein is an alternating connection rotating seal apparatus that includes a stationary element that has at least one fluid path and a rotating element that has at least two fluid paths, such that the rotation of the rotating element results in alternating communication between the at least one fluid path of the stationary element and the at least two fluid paths of the rotating element.

Description

ALTERNATING CONNECTION ROTATING SEAL APPARATUS

RELATED APPLICATIONS

[0001] The present application claims priority to U S Provisional Application Serial No

60/903,485, filed on February 26, 2007, by Fornace et al and entitled "ALTERNATING CONNECTION ROTATION SEAL APPARATUS," which is hereby expressly incorporated by reference in its entirety

FIELD OF THE INVENTION

[0002] The present invention relates to the field of rotating seals that allow increased control of fluid intake and output through multiple fluid paths

BACKGROUND OF THE INVENTION

[0003] Rotating seal assemblies allow fluid communication between rotating and stationary elements of a system Biological samples, e g , cell suspensions, are commonly subjected to centrifugation during processing procedures, m order to separate components of the samples based on, e g , density or both density and size Rotating seals used for addition of fluid to and withdrawal of fluid from centrifuge chambers during cell processing have been described in, e g , U S Pat App Pub No 2005/0084961, "Systems and Methods for Separating and Concentrating Regenerative Cells from Tissue," incorporated herein by reference

[0004] In centrifugation devices utilizing rotating seals, a centrifugation chamber can be emptied by applying a vacuum to a lumen, of the stationary element of the device, that is in communication through the rotating seal with the fluid path lumen leading to the chambers in the rotating element As the seal rotates, the lumen in the stationary element communicates with the lumen in the rotating element Fluid path lumens originating from multiple chambers can merge into a single lumen in the rotating element, which can then communicate with the lumen in the stationary element Unfortunately, because the chambers share a lumen in the rotating element, emptying of any chamber results in a loss of vacuum in the system This prevents complete emptying of the remaining chamber(s) A rotating seal that allows complete emptying of all the chambers in a multi-chamber device has not been described

SUMMARY OF THE INVENTION

[0005] The present invention relates to a rotating seal apparatus that allows communication between fluid paths originating from each of multiple chambers in the rotating element of a multiple chamber device, and at least one fluid path in the stationary element of the device The configuration of this rotating seal apparatus allows fluid to be added to or withdrawn from each of the chambers in an alternating sequence during rotation Rotation of the seal causes the connection between the fluid paths in the stationary and rotating elements to open and close sequentially so the seal acts essentially as a valve As a result, communication between a fluid path of the stationary element and each fluid path in the rotating element occurs separately, providing the user with a point for controlling the addition of fluids to and withdrawal of fluids from the rotating element Separating the communication paths between the stationary element and each chamber in the rotating element of the device prevents a loss of vacuum when one chamber empties

[0006] Specifically, the present invention relates to an alternating connection rotating seal apparatus comprising a stationary element having at least one fluid path, and a rotating element having two or more fluid paths, wherein rotation of the rotating element results in alternating communication between said at least one fluid path and each of said at least two fluid paths In embodiments, said at least one fluid path is in communication with each of said at least two fluid paths during every revolution of said rotating element

[0007] It is contemplated that alternating connection rotating seal apparatus is used in a centrifuge In embodiments each of said at least two rotating element fluid paths is in fluid communication with a separate chamber of the centrifuge It is contemplated that said alternating communication with said at least two rotating element fluid paths allows substantially even addition of fluid to the chambers of the centrifuge apparatus It is further contemplated that said alternating communication with said at least two rotating element fluid paths allows substantially complete withdrawal of fluid from all the chambers of the centrifuge apparatus

[0008] In specific embodiments, the seal of the alternating connection rotating seal apparatus uses a face seal The alternating connection rotating seal apparatus can be configured as shown in Figure 1 In certain embodiments, the stationary element having at least one fluid path comprises a first disc, and wherein the rotating element having two or more fluid paths comprises a second disc In embodiments, the first disc has two fluid paths In particular embodiments, the second disc has three fluid paths, or four fluid paths, or five fluid paths Embodiments in which the first disc has one fluid path and said second disc has two fluid paths are also contemplated

[0009] In other embodiments, the stationary element having at least one fluid path comprises a housing, and said rotating element having two or more fluid paths comprises a shaft In particular embodiments, the alternating connection rotating seal apparatus is configured as shown in Figure 7 Use of a lip seal in this apparatus is also contemplated In embodiments, said housing has one fluid path and said shaft has two fluid paths

[0010] It is further contemplated that the alternating connection rotating seal apparatus of the invention be provided as part of a disposable set for a device In embodiments, the device is a tissue-processing device In further embodiments, the tissue-processing device is used for processing adipose tissue

[0011] The invention includes a method for processing cells in a tissue-processing device, comprising conveying said cells through the alternating connection rotating seal apparatus comprising a stationary element having at least one fluid path, and a rotating element having two or more fluid paths, wherein rotation of the rotating element results in alternating communication between said at least one fluid path and each of said at least two fluid paths In embodiments, said cells are derived from adipose tissue

[0012] In embodiments of these methods, the alternating connection rotating seal apparatus is disposable In further embodiments, the alternating connection rotating seal apparatus used in these methods is provided as part of a disposable set for said tissue-processing device

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 An alternating connection rotating face seal apparatus. The drawing shows the external view of a rotating face seal apparatus of the present invention, including the rotating base 10, stationary cap 11 and connectors 12 and 13 The connectors originate from the lumen openings and allow attachment to other components, e g , cap connectors 12 can lead to a pump, and base connectors 13 can lead to centrifuge chambers It is understood that any type of appropriate connecting means can be used at the lumen openings

[0014] Figure 2 Exploded 3-D diagram of an alternating connection rotating face seal apparatus illustrated in Fig. 1 An exploded diagram of a rotating face seal apparatus reveals a stationary disc 14, having a single fluid path lumen 17 and a screw hole 19 for the screw 16 which performs both a retaining and bearing function The rotating disc 15 has two fluid path lumens 30 (shown in Fig. 4), one in the recessed area of each of the two fluid channels 18 The fluid path lumens in the rotating disc communicate with fluid path lumens 32 in the base of the apparatus 10 0-rmgs 20 can be located at each fluid path junction between the rotating disc and the base

[0015] Figure 3 Stationary disc of an alternating connection rotating face seal apparatus illustrated in Figures 1 and 2 The disc 14 shown has one fluid path lumen 17 In other embodiments, the disc has multiple fluid path lumens, e g , two fluid path lumens could be located between the and the screw hole 19 and the perimeter of the disc, in alignment with the screw hole 19 (i e , along the dotted line in the diagram) 3A. Top view The verticle cutting plane used to generate the cross-section shown in Fig 3B bisects stationary disc fluid path lumen 17, as indicated by the dotted line 3B. Cross-sectional view

[0016] Figure 4 Rotating disc of an alternating connection rotating face seal apparatus illustrated in Figures 1 and 2. The rotating disc 15 shown here has two fluid channels 18 and two rotating disc fluid path lumens 30 4A. Top view of the disc The verticle cutting plane used to generate the cross-section shown in Fig 4B bisects the rotating disc fluid path lumens 30, as indicated by the dotted line 4B. Cross-sectional view

[0017] Figure 5 Cap of an alternating connection rotating face seal apparatus illustrated in Figures 1 and 2. 5A. Bottom view of a cap 11 having one fluid path lumen 31 The verticle cutting plane used to generate the cross-section shown in Fig 5B bisects cap fluid path lumen 31, as indicated by the dotted line 5B. Cross-sectional view showing the external opening of the cap fluid path lumen 31, which can lead to a pump, and a screw recess 21

[0018] Figure 6 Base of an alternating connection rotating face seal apparatus illustrated in Figures 1 and 2. The base 10 shown has two fluid path lumens 32 6A. Top view The verticle cutting plane used to generate the cross-section shown in Fig 6B bisects both base fluid path lumens 32, as indicated by the dotted line 6B. Cross-sectional view showing the external openings of the two base fluid path lumens 32, to which connectors 13 can be attached as indicated in Fig. 1

[0019] Figure 7 Exploded 3-D diagram of an alternating connection rotating lip seal apparatus. The drawing shows an exploded view of an an alternating connection rotating lip seal apparatus of the present invention, having a stationary housing 24 and rotating shaft 25 Bearings 22 and seals 23 are positioned at the upper and lower ends of the apparatus housing Plugs 26 can be used to close openings generated by drilling the lumens

[0020] Figure 8 Cross-sectional sketch of an alternating connection rotating lip seal apparatus illustrated in Figure 7. The cross-section was generated using a vertical, centered cut through the mtact apparatus The cutting plane bisects the stationary housing fluid lumen 33 In the drawing, the stationary housing fluid lumen 33 is in communication with one shaft fluid lumen 34 The second shaft fluid lumen 34 is shown in a closed position

[0021] Figure 9 Cross-sectional sketch of an alternating connection rotating lip seal apparatus. 9A. Cross-sectional view as shown in Figure 8, indicating the transverse cutting plane used for the cross-sectional view shown in Fig 9B 9B. Transverse cross- section. The upper segment of the apparatus, generated when cut as shown in Fig. 9A, is viewed from below. Axial seals 28 extending vertically from an upper to lower seal (both 23) are located at each end of the well.

[0022] Figure 10 A stationary housing for an alternating connection rotating lip seal apparatus illustrated in Figure 7. 1OA. A 3-D drawing of the the housing. Dotted lines indicate the centered vertical cutting plane used to generate the cross-sectional view in Fig. 1OB The cutting plane bisects fluid path lumen 17 1OB. Cross-section of the stationary housing, showing one of the two axial seals 28.

[0023] Figure 11 Views of a shaft for an alternating connection lip seal apparatus illustrated in Fig. 7. The locations of the shaft fluid path lumen 34 and shaft base fluid path lumen 35, which are joined and in communication with one another (as visible in the cross- sectional views in Figs. 8 and 9A), are shown. HA. Isometric view HB. Front view.

DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention relates to a rotating seal apparatus that allows increased control over communication between fluid paths originating from each of multiple chambers in the rotating element of a multiple chamber device, and at least one fluid path in the stationary element of the device. The communication between fluid paths is regulated by the rotation of the device, thereby allowing fluid to be added to and withdrawn from the rotating element in a controlled manner. The device can be, e.g., a centrifuge used for automated sample processing. In an automated centrifugation device, control over addition and withdrawal of fluid are crucial for maintaining centrifuge chamber balance Furthermore, separating the communication paths between the stationary element and each chamber in the rotating element of the device prevents a loss of vacuum when one chamber empties.

[0025] In embodiments, the alternating connection rotating seal of the invention is disposable, i.e , it is provided as part of a single use, sterile disposable processing set that interfaces with a system, e g., a tissue or blood processing system The sterile disposable set can include an alternating connection rotating seal apparatus and centrifuge chambers, e.g., swinging bucket chambers, as well as any appropriate means as known to one of skill in the art for conveying material to and from the rotating seal apparatus.

[0026] Citation of documents herein is not intended as an admission that any of the documents cited herein is pertinent prior art, or an admission that the cited documents are considered material to the patentability of the claims of the present application. All statements as to the date or representations as to the contents of these documents are based on the information available to the applicant and do not constitute any admission as to the correctness of the dates or contents of these documents

I. Systems Utilizing Alternating Connection Rotating Seals

[0027] The rotating seals of the present invention are useful in any device or system that requires fluid communication between multiple lumens in a moving element and at least one lumen in a stationary element For example, as described herein, the rotating seals of the invention are useful in a centrifugation device wherein fluid is pumped into or out of more than one centrifugation chamber.

[0028] It is understood that certain processes as defined by the user will impose specific limitations or requirements that will affect the exact design and use of the rotating seals of the present invention. For example, those of skill in the art will understand that in cell processing applications, the temperature cannot exceed that which might compromise the function or viability of the cells As an example, it could be desirable to maintain a cell solution temperature at or below about 42⁰C. This would require that the rotating seal apparatus be constructed to minimize heat generation caused, e g , by friction

[0029] Use of the apparatus of the present invention for automated or partially-automated processing of any appropriate fluid, including, but not limited to, cell suspensions, including blood, blood components, other blood products, and other body fluids, is contemplated.

II. Alternating Connection Rotating Seals

[0030] The alternating connection rotating seal apparatus of the present invention can utilize a rotating face seal, a rotating lip seal, or another type of seal, depending on user preference. Other types of seals known to those of skill in the art can also be used. In embodiments, there are two, three, four or more lumens in the moving element and one, two, three or more lumens in the stationary element

[0031] Those of skill in the art will understand that the teachings disclosed herein make available numerous ways of building an alternating connection rotating seal of the present invention The apparatus of the present invention can be constructed by strategies not specifically described herein but known to those of skill in the art, using components of varying shapes, sizes and materials familiar to those of skill in the art Components can be fabricated using any appropriate method known to those of skill in the art, e g , machining, molding, or casting

Alternating Connection Rotating Face Seal

[0032] An alternating connection rotating face seal apparatus, e g , as shown in Figures 1 -6, comprises a rotating disc 15 having at least two fluid paths 30 During chamber filling, fluid can be pumped into the cap fluid path lumen 31 from outside the seal The cap fluid path lumen opening on the bottom face of the cap is aligned with fluid path lumen 17 on the attached stationary disc, therefore, after traveling through cap fluid path lumen 31, the fluid travels through stationary disc fluid path lumen 17

[0033] With each rotation of the rotating disc relative to the stationary disc, the fluid in stationary disc fluid path lumen 17 communicates with each rotating disc fluid channel 18. In a rotating face seal apparatus of the invention having two fluid channels 18 in the rotating disc, one rotation results in one period of fluid communication between fluid path lumen 17 and each fluid channel 18, with one period of interruption in communication between each period of communication, i e , two periods each of communication and interruption In an apparatus of the present invention having four rotating disc fluid channels 18 (or four fluid path lumens 34 as described below in relation to a housing/shaft rotating seal apparatus), one rotation of the seal would include four periods each of communication and interruption

[0034] Each fluid channel 18 is in continuous communication with a rotating disc fluid path lumen 30, therefore after entry into a fluid channel, the fluid enters corresponding lumen 30 and from there moves into base fluid path lumen 32 The base 10 rotates with the rotating disc The rotating base can be made, e g , by machining from acetal or any other appropriate material It is understood that for uses involving the passage of live cells through the seal, a biocompatible material should be used for any part that contacts the cells From base fluid path 32 the fluid exits the seal apparatus, e g , through a connector 13 or another connection means, then can travel through tubing or the equivalent to its destination, e g , a centrifuge chamber

[0035] During emptying of the chambers, fluid from the chambers can be pumped out of the chambers and back through the seal It is significant to note that a vacuum is applied to each rotating disc fluid path lumen 30 (and thus each chamber) independently Thus, when one chamber empties and the vacuum breaks in that fluid path, the vacuum force in the fluid path to every other chamber is maintained This feature of the present invention allows substantially complete withdrawal of the fluid from every chamber, regardless of order in which the chambers empty

[0036] The fluid channels comprise a recessed area in the rotating disc The openings to the fluid paths 23 in the rotating disc are each situated within a fluid channel 18, resulting in communication between the fluid path and channel In embodiments, the size of the fluid channel is selected to fit the process For example, shorter fluid channels allow less communication time and therefore less fluid transfer (per rotation) between the fluid path 23 of the rotating disc and the fluid path 19 of the stationary disc The greater the length of a fluid channel, the more time the stationary disc fluid path is in communication with the rotating disc fluid channel and fluid path Therefore, more fluid can be pumped through the connection with each rotation of the seal On the other hand, an increase in the length of the fluid channel results in a decrease in the separation between the ends of multiple fluid channels in the disc This could potentially increase the likelihood of leakage between adjacent fluid channels

[0037] The valving action created by the alternating communication between the fluid path lumens in the stationary and rotating elements of the seal provides a built-in mechanism for substantially even addition of fluids Substantially even addition of fluids to chambers in a centrifuge results in a balanced centrifuge Different centrifuges and chamber set-ups have different tolerances for imbalance, as known to those of skill in the art

[0038] Control over fluid channel and lumen size could allow a user to unevenly distribute fluids as well, if so needed For example, a rotating disc in a face seal apparatus could be constructed with fluid channels of differing lengths or lumens of differing diameters In a centrifuge having four chambers or buckets, alteration of the fluid channels in the rotating disc could be used to fill one pair of chambers substantially evenly yet to a volume differing from that of the second pair of chambers The second pair of chambers could also be filled using a separate set of stationary and rotating fluid path lumens located in a different circular path (a different concentric circle) on the discs

[0039] In embodiments, the fluid paths and channels are present in multiple concentric circular paths, allowing the addition of separate fluid paths through the seal

[0040] The stationary disc 14 can be comprised of any appropriate material, including, e g , ceramic (e g , alumina ceramic), silicon carbide, or the like, provided that the material is suitable for use with that material from which the rotating disc is comprised Appropriate pairing of materials can be assessed by one of skill in the art It is generally understood that pairing dissimilar materials will result in better wear of the disc For example, a ceramic stationary disc can be used with a ceramic or graphite rotating disc, and a silicon carbide stationary disc can be used with a graphite or ceramic rotating disc

[0041] Depending on design requirements, the seal faces (rotating and stationary discs) can be made from materials including, but not limited to, ferrous metals (e g , carbon, alloy, stainless, and tool and die steels), nonferrous metals and alloys (e g , aluminum, magnesium, copper, nickel, titanium, superalloys, refractory metals, beryllium, zirconium, low-melting alloys, precious metals, etc ), plastics (e g , thermoplastics, thermosets, elastomers, etc ), ceramics (e g , glass ceramics, glasses, graphite, diamond, etc ), or composite materials (e g , reinforced plastics, metal-matrix and ceramic-matrix composites, and sandwich structures)

[0042] The size and conformation of the fluid paths in the stationary or rotating disc, or the fluid channels in the rotating disc, can be optimized for the desired use by methods known to those of skill in the art The fluid paths and central hole for screw attachment can be made by any appropriate method, e g , machining, drilling or injection molding One of skill in the art will understand that the timing of the valvmg action is influenced by the arclengths of the rotating disc's fluid paths, as well as the size of the fluid path in the stationary disc

[0043] The cap 11 can be made of any appropriate rigid material, e g , polycarbonate, plastic, aluminum, steel, etc A cap connector 12 or other connection means can be attached to the cap at the external opening of cap fluid path lumen 31 to allow attachment of, e g , a tube or tubes leading to other containers, a pump, etc The stationary disc 14 can be attached to the cap, e g , by gluing or by mechanical retention with a lip or using screws Any appropriate glue, e g , epoxies, etc , can be used One of skill in the art will understand that the glue type selected should properly bond the materials used to make the parts to be glued together

[0044] The central hole 20 in components of the apparatus allows them to be held together with a screw 16 as shown in the Figures Downward pressure can be applied in any of a number of ways known to those of skill in the art and described in the literature to the top of the cap to maintain a sufficient seal between the rotating and stationary discs

Rotating Shaft/Stationary Housing Alternating Connection Rotating Seal

[0045] An alternating connection rotating seal having a rotating shaft and stationary housing configuration is shown in Figures 7-11 This alternating connection rotating seal can also be used to empty and fill multiple chambers, and to maintain a vacuum in all chambers regardless of emptying of one chamber

[0046] During chamber filling, fluid enters the seal through stationary housing fluid path lumen 33 The housing is fitted over a rotating shaft 25 The stationary housing fluid lumen is in alternating communication with one shaft fluid lumen 34 An engineered difference between the size of the shaft and the housing volume leaves a well 29 between the shaft and the lumen side of the housing This well extends the period of fluid communication between the housing fluid path lumen 33 and each shaft/base fluid path lumen 34/35 by serving as a sort of widened mouth for the housing fluid path lumen 33 Its function can be compared to the function of the fluid channels 18 in the alternating connection rotating face seal described above [0047] During operation of the rotating seal, fluid entering the apparatus, e g , from housing fluid path lumen 33, fills the well 29 When the mouth of shaft fluid path lumen 34 is open to well 29, fluid flows through the shaft base fluid path lumens 35 and out of the seal A countersink 27 at the mouth of shaft fluid path lumen 34 can also be varied in size to further influence the ease of fluid communication between housing lumen 33 and shaft lumen 34 (through well 29)

[0048] The process can be reversed and the chambers emptied in a manner similar to that described for the rotating face seal, also without loss of vacuum when a chamber empties

[0049] The housing components can be made of any material deemed appropriate, e g , thermoplastics or thermoset polymers, based on the requirements of individual designs The shaft/housing alternating connection seal can be constructed wherein the seal 22 is any elastomer seal, including, but not limited to, a lip seal, O-ring, or packing, as long as the appropriate temperature and other desired parameters are maintained using the seal

[0050] Fluid can be pumped through a rotating seal, and the pumping pressure regulated, by mechanisms known to those of skill in the art Such mechanisms include pumps known in the art and described in the literature, and can include the use of control circuitry as known to those of skill in the art

Modes of Carrying out the Invention

[0051] It is to be understood that this invention is not limited to particular formulations or process parameters, as these may, of course, vary It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only, and is not intended to be limiting Further, it is understood that a number of methods and materials similar or equivalent to those described herein can be used in the practice of the present invention

[0052] As discussed, an alternating connection rotating seal apparatus can be used in any device or system that requires fluid communication between multiple lumens in a moving element and at least one lumen in a stationary element For example, the apparatus of the present invention could be used in an automated cell processing device used for processing cells from adipose tissue, e g , as described in U S Pat App Pub No 2005/0084961, "Systems and Methods for Separating and Concentrating Regenerative Cells from Tissue "

[0053] In embodiments, the alternating connection rotating seal apparatus of the invention is disposable, and can be provided as part of a disposable set that interfaces with the device or system in which the alternating connection rotating seal apparatus is used The use of sterile disposable sets is known in the art and has been described extensively in the literature, e g , in U S Pat App Pub No 2006/0021952, "Apparatus for Separating Blood Components," incorporated herein by reference

[0054] The contents of all cited references, including literature references, issued patents, published patent applications, and co-pending patent applications, cited throughout this application are hereby expressly incorporated by reference in their entirety

EXAMPLES

[0055] The present invention is further illustrated by the following examples, which should not be construed as limiting in any way

Example I: Construction of an Alternating Connection Rotating Face Seal

[0056] An alternating connection rotating face seal of the invention similar to that shown in

Figures 1-6 having a rotating disc with a single fluid path and a stationary disc with two fluid paths, was constructed The rotating base was machined from black acetal using CNC Lathes and Mills The cap was machined from polycarbonate rod The stationary disc was machined from a free machining grade alumina ceramic, and the rotating disc was machined from compressed graphite

Example II: Fluid Metering Using an Alternating Connection Rotating Face Seal

[0057] The ability of an alternating connection rotating face seal to effectively meter fluid into and out of dual swinging bucket centrifuge chambers (designated in Tables 1 and 2 as A and B) was evaluated A face seal apparatus of the invention as described in Example I was connected to 225ml swinging bucket chambers (BD-Falcon Conical Bottom Polypropylene tubes, part number 352075) Saline was pumped through flexible PVC tubing (1/8" inside diameter) to the chambers through the seal from a saline container outside the seal The lines were primed, and saline was pumped into the centrifuge chambers through the fluid path under low pressure (below 1 psi) for 40 seconds at a centrifuge speed of 200 rpm

[0058] The volume of fluid received by each chamber is shown in Table 1

[0059] The results show good consistency (within 4% on average) between the volumes delivered to each swinging bucket chamber. For applications requiring centπfugation speeds appropriate for pelleting blood cells, centrifuge balance can be attained if the volume difference between opposing buckets does not exceed, e.g., about 20%

[0060] To address the possibility that the difference in filling was due to differences between the buckets themselves, buckets A and B were switched in position relative to the seal The results are shown in Table 2.

[0061] The average volumes were again within a desirable range. As before, bucket A collected more fluid than bucket B, indicating that the difference in volumes observed was a function of the buckets themselves rather than the buckets' position relative to the seal.

Example HI: Fluid Aspiration Using an Alternating Connection Rotating Face Seal

[0062] The ability of an alternating connection rotating face seal to effectively pump fluid into and out of dual swinging bucket centrifuge chambers (designated A and B) was assessed An experiment similar to that described in Example II was performed, except that the pump was run in reverse to withdraw fluid from the chambers To approximate the situation in which one bucket has emptied first, approximately 20 ml saline was placed in bucket A, and nothing in bucket B Both buckets were drained at a centrifuge speed of 100 rpm and below

Claims

We claim:

1 An alternating connection rotating seal apparatus comprising a stationary element having at least one fluid path, and, a rotating element having at least two fluid paths, wherein rotation of the rotating element results in alternating communication between said at least one fluid path and each of said at least two fluid paths

2 The alternating connection rotating seal apparatus of claim 1 , wherein said at least one fluid path is in communication with each of said at least two fluid paths during every revolution of said rotating element

3 The alternating connection rotating seal apparatus of claim 1 , wherein said apparatus is used in a centrifuge

4 The alternating connection rotating seal apparatus of claim 3, wherein each of said at least two rotating element fluid paths is in fluid communication with a separate chamber of the centrifuge

5 The alternating connection rotating seal apparatus of claim 3, wherein said alternating communication allows substantially even addition of fluid to the chambers of the centrifuge apparatus

6 The alternating connection rotating seal apparatus of claim 3, wherein said alternating communication allows substantially complete withdrawal of fluid from all the chambers of the centrifuge apparatus

7 The alternating connection rotating seal apparatus of claim 1 , wherein said seal is a face seal

8 The alternating connection rotating seal apparatus of claim 7, configured as shown in Figure 1 9 The alternating connection rotating seal apparatus of claim 7, wherein the stationary element having at least one fluid path comprises a first disc, and wherein the rotating element having two or more fluid paths comprises a second disc

10 The alternating connection rotating seal apparatus of claim 9 wherein said first disc has two fluid paths

11 The alternating connection rotating seal apparatus of claim 9 wherein said second disc has three fluid paths

12 The alternating connection rotating seal apparatus of claim 9 wherein said second disc has four fluid paths

13 The alternating connection rotating seal apparatus of claim 9 wherein said second disc has five fluid paths

14 The alternating connection rotating seal apparatus of claim 9 wherein said first disc has one fluid path and said second disc has two fluid paths

15 The alternating connection rotating seal apparatus of claim 1 , wherein said stationary element having at least one fluid path comprises a housing, and wherein said rotating element having two or more fluid paths comprises a shaft

16 The alternating connection rotating seal apparatus of claim 15 wherein said housing has one fluid path and said shaft has two fluid paths

17 The alternating connection rotating seal apparatus of claim 15 configured as shown in Figure

7

18 The alternating connection rotating seal apparatus of claim 1 wherein said apparatus is provided as part of a disposable set for a device

19 The alternating connection rotating seal apparatus of claim 18 wherein said device is a cell- processing device

20 The alternating connection rotating seal apparatus of claim 19 wherein said cell-processing device is used for processing adipose tissue

21 A method for processing cells in a cell-processing device, comprising conveying said cells through the alternating connection rotating seal apparatus of claim 1

22 The method of claim 21 wherein said cells are derived from adipose tissue

23 The method of claim 21 wherein said alternating connection rotating seal apparatus is disposable

24 The method of claim 23 wherein said alternating connection rotating seal apparatus is provided as part of a disposable set for said cell-processing device