The above and other aspects, features and advantages of the present invention will be more apparent from the following more particular description thereof, presented in conjunction with the following drawings wherein:
Corresponding reference characters indicate corresponding components throughout the several views of the drawings.
The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims.
A disposable mass transfer system 10 according to the present invention is shown in
The sealed fluid flow channels 12a and 12b reside in (or are formed by) a flexible sealed reservoir (dialysis chamber) 11, or in other embodiments, the sealed fluid flow channels 12a and 12b may comprise tubes. Each of the sealed fluid flow channels 12a and 12b contain at least one of the semi-permeable tubular membranes 14a, 14b, and the channels 12a and 12b fluidly cooperate to create a sequentially flow through the channels 12a and 12b. The semi-permeable tubular membranes 14a, 14b are preferably regenerated cellulose tubing preferably with a flat width ranging between approximately 3 mm and 340 mm and more preferable with a flat width ranging between approximately 8 mm and approximately 16 mm. The flexible sealed reservoir 11 is preferably made from PVC and the flow channels 12a and 12b are integrally formed in the flexible sealed reservoir 11 by RF welding, wherein a wall 17 separates the channels 12a and 12b.
The flexible plastic reservoir 11 includes hermetically sealed fluid inlet and outlet ports 15a and 15b respectfully, to allow connection of the flow channels 12a and 12b to external tubing 34c and 34d respectively using tube to tube connectors 26. The external tubing 34c carries a first (or inlet) flow of dialysis fluid 13a (or mass transfer exchange fluid) into the channel 12a, and the external tubing 34d carries a second (or outlet) flow of dialysis fluid 13b out of the flow channel 12b. The dialysis fluid circulates from the chamber 12a into the chamber 12b in a third flow of dialysis fluid 13c. The first flow of dialysis fluid 13a may be fresh dialysis fluid, or may be partially spent dialysis fluid being re-circulated as described below. The second flow of dialysis fluid 13b may be partially spent dialysis fluid suitable for re-circulating as described below, or may be fully spent dialysis fluid. The flows 13a and 13b circulate tangentially along outer surfaces of the semi-permeable tubular membranes 14a and 14b.
The port 15a receives the fresh dialysis fluid from a source of dialysis fluid 36 through serially connected tube 34a, tube 34b, pump 28, and the tube 34c (i.e., through inlet tubes). The outlet port 15b releases spent dialysis fluid to a waste fluid reservoir 38 through serially connected tube 34d and tube 34e (i.e., through outlet tubes). The source of dialysis fluid 36 is preferably a bulk reservoir container (for example a bottle) and the waste fluid reservoir 38 is preferably a waste reservoir container. The pump 28 provides propulsion of dialysis fluid through the tubing 34a-34c, through the flow channels 12a and 12b, through the tubing 34d and 34e, and into the waste fluid reservoir 38.
The port 15a may also receive the partially spent dialysis fluid through serially connected tube 34d, tube 34f, tube 34b, pump 28, and tube 34c, thereby re-circulating the partially spent dialysis fluid through the sequentially connected flow channels 12a and 12b. The tube 34f is a shunt tube carrying a shunt flow 13d and is connected between the inlet tubes and the outlet tubes to provide the re-circulating, and preferably the tube 34f is connected between the tubes 34a and 34b by a first “T” 30a and is connected between the tubes 34d and 34e by a second “T” 30b. The pump 28 is preferably a peristaltic pump and the tubes 34b and 34c are preferably a single continuous tube.
A first pinch clamp 32a resides on the tube 34a, a second pinch clamp 32b resides on the tube 34e, and a third pinch clamp 32c resides on the tube 34f. The pinch clamp 32c may be used to pinch (i.e., close) tube 34f, thereby connecting the source of dialysis fluid 36 to the flow channels 12a and 12b through the pump 28, and connecting the flow channels 12a and 12b to the waste fluid reservoir 38. Alternatively, the pinch clamps 32a and 32b may be used to pinch the tubes 34a and 34e, thereby connecting the pump 28 to re-circulate the partially spent dialysis fluid. While pinch clamps 32a-32c is preferred, any suitable on-off valve or clamp may be used to selectively block or clamp the tubes 34a, 34e, and 34f.
The semi-permeable tubular membranes 14a, 14b have an open end and a closed end. The closed ends are preferably sealed by plugs 16 held in place by a sleeve and collet 18. An example of a suitable plug 16 is a part number AP01PLG25P made by ARK-PLAS INC. in Flippin, Ark. An example of a suitable sleeve and collet is a part number BL135250W made by Barblock in Traverse City, Mich. A conduit 22 is connected to the open end of each of the semi-permeable tubular membranes 14a, 14b. The conduit members 22 preferably have one end hermetically sealed to the semi-permeable tubular membranes 14a, 14b by plastic needleless access injection port fittings. The conduit members 22 pass through the walls of the flexible sealed reservoir 11 and the flow channels 12a and 12b and connect to hermetically sealed needleless injection access sites 24. An example of a suitable needleless connection site is a part number 8014F made by QOSINA in Edgewood, N.Y. The conduit members 22 are preferably sealed to the walls of the flexible plastic reservoir 11 by heat sealing. The access sites 24 are preferably able to allow access to the interior space of the semi-permeable tubular membranes 14a, 14b by a hypodermic needle and preferably allow access using other needleless access means. Further, the flexible plastic reservoirs 11 is provided with a third, hermetically sealed access site 40 to serve as means to access the interior cavities of said reservoir.
A second disposable mass transfer system 50, includes the fluid flow channels 12a and 12b comprising semi-rigid or rigid tubular enclosures 52a and 52b, and preferably a clear medical grade plastic resin such as PVC, polycarbonate, Lexan® resin, polysulfone and the like, containing the tubular semi-permeable membranes 14a and 14b as shown in
A third disposable mass transfer system 60 includes the fluid flow channels 12a and 12b comprising the semi-rigid or rigid tubular enclosures 52a and 52b containing the tubular semi-permeable membranes 14a and 14b as shown in
A fourth disposable mass transfer system 70 includes a single channel 12a comprising the semi-rigid or rigid tubular enclosure 52a containing the tubular semi-permeable membrane 14a as shown in
A fifth embodiment of the disposable mass transfer system 80 according to the present invention, having two semi-rigid or rigid tubular enclosures 52a and 52b in parallel, is shown in
The tube 34h is connected to the port 15a by a tube connector 26 and the tube 34j is connected to the port 15b by another tube connector 26. Tubes 34k and 34l connect outlet ports 15c and 15d of the enclosures 52a and 52b respectively to the waste fluid reservoir 38. Pinch clamps 32f and 32g reside on tubes 34k and 34l respectively and may be used to control a flow through the tubes 34k and 34l. The disposable mass transfer system 80 is otherwise similar to the disposable mass transfer system 50.
The disposable mass transfer systems 50, 60, 70, and 80 may further be expanded into a multiplicity of sequentially connected semi-rigid or rigid tubular enclosures, and an individual semi-rigid or rigid tubular enclosures may be enlarged to contain more than one tubular semi-permeable membranes.
Typical dialysis applications include desalting, concentrating plasma or serum, buffer and pH change of sample solution, preparation of diluted proteins prior to electrophoresis, concentration of antibodies, contamination removal, binding studies, batch analysis temperature regulated dialysis, tissue culture extract purification, protein removal from gels after electrophoresis removal of olizosaccharides from protein solutions. These are examples of typical applications for the invention. (Ref. The ABCs of Filtration and Bioprocessing for the Third Millennium, page 68, by Ballew, Martinez, Markee, and Eddleman).
While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims.