Liquid purification or separation – Processes – Separating
Patent
1995-03-31
1997-09-23
Kim, John
Liquid purification or separation
Processes
Separating
210782, 210787, 210789, 210806, 604 4, B01D 3700, B01D 2126
Patent
active
056700601
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention concerns a device and method for processing biological fluid.
BACKGROUND OF THE INVENTION
Blood consists of a number of components having different characteristics and uses. The separation of a single unit of donated whole blood into its components is typically accomplished by use of differential sedimentation. The principal components thus recovered are red cells, usually concentrated as packed red cells (PRC), a platelet suspension, usually concentrated as platelet concentrate (PC), and plasma.
There are two principal methods for separation of whole blood into components. In one method, the whole blood is centrifuged to produce a supernatant PRP fraction and a sediment PRC fraction, with a transition zone material in between, generally known as the buffy coat, which contains leukocytes, as well as platelets, red cells, and plasma. The PRP fraction is separated from the buffy coat and the PRC and centrifuged to produce a supernatant plasma fraction and a sediment platelet-containing fraction. The two fractions are then separated, and the platelet-containing fraction is processed to form PC.
In an alternative method, the whole blood is centrifuged to produce a supernatant platelet-poor plasma (PPP) fraction, and a sediment PRC fraction, with a transition zone material, the buffy coat, therebetween, which contains the majority of platelets, as well as leukocytes, red cells, and plasma. The buffy coat is separated from the supernatant PPP and the sediment PRC and centrifuged to form a supernatant platelet-containing fraction, and a sediment red cell containing fraction. The supernatant platelet-containing fraction is then separated from the sediment fraction, and processed to form PC.
Drawbacks of both techniques include the potential for contamination with red cells and/or leukocytes. With respect to red cell contamination, the presence of red cells in some blood components (e.g., PC) is so undesirable that the technician operating the blood processing equipment during the separation of components typically constantly monitors the process, and clamps the connecting tube between the blood bags when, in his judgment, as much fluid has been transferred as is possible, without allowing red cells to pass into the downstream satellite bag. This is a labor intensive and time consuming operation.
Red cell contamination presents an additional dilemma. Since platelets and plasma are valuable, blood bank personnel may attempt to express more of the PRP or the supernatant platelet-containing fraction into the satellite bag prior to stopping the flow from the collection bag. This is counterproductive in that the expressed fluid in the satellite bag may be contaminated by red cells, so that the expressed fluid may have to be discarded or recentrifuged, both of which increase operating costs and are labor intensive. As a result, blood bank personnel may prematurely stop the flow of the platelet-containing fluid before it has been fully expressed.
The techniques described above for separation of whole blood into components may also produce leukocyte contaminated components. It is desirable to reduce the leukocyte concentration of each of the blood components by at least 70%, since the presence of leukocytes may adversely affect the storage life of the fractions, and/or cause undesirable effects when the fractions are transfused into a patient.
In view of these problems, it may be difficult to eliminate red cell and leukocyte contamination while maximizing the yield of the various blood components in the transition zone material or the buffy coat. For example, since it may be difficult to easily or efficiently separate the platelets, plasma, and red blood cells, and leukocyte deplete them, the buffy coat may be partially or entirely discarded, resulting in reduced yields of valuable blood components such as plasma and platelets.
The loss of platelets is especially significant, since the discarded portion may include the most desirable platelets, i.e., the newly formed platelets. The
REFERENCES:
patent: 3000540 (1961-09-01), Wheeler
patent: 3911918 (1975-10-01), Turner
patent: 4223695 (1980-09-01), Muetterties
patent: 4416772 (1983-11-01), Sato et al.
patent: 4507119 (1985-03-01), Spencer
patent: 4608178 (1986-08-01), Johansson et al.
patent: 4857190 (1989-08-01), Wada et al.
patent: 4985153 (1991-01-01), Kuroda et al.
patent: 4997577 (1991-03-01), Stewart
patent: 5053127 (1991-10-01), Schoendorfer et al.
patent: 5071570 (1991-12-01), Shiraki et al.
patent: 5100564 (1992-03-01), Pall et al.
patent: 5102407 (1992-04-01), Carmen et al.
patent: 5126054 (1992-06-01), Matkovich
patent: 5128048 (1992-07-01), Stewart et al.
patent: 5152905 (1992-10-01), Pall et al.
patent: 5180504 (1993-01-01), Johnson et al.
patent: 5217627 (1993-06-01), Pall et al.
patent: 5258126 (1993-11-01), Pall et al.
patent: 5316674 (1994-05-01), Pall et al.
patent: 5364526 (1994-11-01), Matkovich et al.
patent: 5451321 (1995-09-01), Matkovich
patent: 5470488 (1995-11-01), Matkovich et al.
patent: 5472621 (1995-12-01), Matkovich et al.
patent: 5512187 (1996-04-01), Buchholz et al.
patent: 5527472 (1996-06-01), Bellotti et al.
patent: 5804465 (1996-12-01), Pall et al.
Kretschmer et al., "Improvement of Blood . . . New Bag System", Infusionstherapie, 15:232-239 (Jun. 1988).
Murphy, "Preparation and Storage of Platelet Concentrates", Principles of Transfusion Medicine, pp. 205-213 (1991).
Pietersz et al., "Preparation of Leukocyte-Poor . . . from Buffy Coats", Vox Sang., 53:208-213 (1987).
Pietersz et al., "Platelet Concentrates Stored . . . Glucose-Mannitol System", Vox Sang., 49:81-85 (1985).
Bormann Thomas J.
Gsell Thomas C.
Matkovich Vlado I.
Morris Keith S.
Pascale Frank R.
Kim John
Pall Corporation
LandOfFree
Method for treating a biological fluid including transition zone does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for treating a biological fluid including transition zone, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for treating a biological fluid including transition zone will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1937716