US3914985A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Centrifuging device and method
Assignee: Baxter Healthcare Corp
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Filing: 1974-03-29
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Granted: 1975-10-28
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Expires: 1994-03-29
Abstract
Abstract A device and method for harvesting, compacting and measuring particulate matter, especially cellular matter, suspended in liquids such as blood and other body fluids. The device comprises an outer tube which is closed at its lower end and which contains a removable inner tube, the latter having an upper section defining an enlarged chamber and having a transparent lower section provided with a capillary passage communicating with the chamber. After an initial centrifuging operation in which particulate matter to be measured has collected in the capillary passage, the inner tube is removed and the lower capillary section is separated and is thereafter re-centrifuged at higher speed to compact for optical volumetric measurement the particulate matter under investigation. In one embodiment, the lower end of the capillary tube is open and communicates directly with the interior of the outer tube so that during initial centrifugation an equilibrating flow of liquid and particulates takes place to displace from the inner tube substantially all but the uppermost strata of particulates. Variations in operation and in structure for supporting the inner tube within the outer tube are also disclosed.
Inventors
- 👤 Behrens Wieland E Von
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:19
CPC Classifications
B; B01; B01L; B01L3/00; B01L3/50; B01L3/502; B01L3/5021; G; G01; G01N; G01N15/00; G01N15/04; G01N15/042; G01N33/00; G01N33/48; G01N33/483; G01N33/487; G01N33/49; G01N33/491
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
80 words
A centrifuge tube assembly comprising an open-topped outer tube and an inner tube removably supported therein; said inner tube having an upper section defining an enlarged chamber and a lower section having a capillary passage communicating with said chamber; said lower section being transparent and being separable from said upper section when said inner tube is removed from said outer tube; said capillary passage being open at its bottom end and communicating directly with the interior of said outer tube.
Claim 2
Dependent Claim
80 words
A centrifuge tube assembly comprising an open-topped outer tube and an inner tube removably supported therein; said inner tube having an upper section defining an enlarged chamber and a lower section having a capillary passage communicating with said chamber; said lower section being transparent and being separable from said upper section when said inner tube is removed from said outer tube; said capillary passage being open at its bottom end and communicating directly with the interior of said outer tube.
Claim 3
Dependent Claim
28 words
The tube assembly of claim 1 in which the bottom end portion of said lower capillary section is spaced above the bottom inside surface of said outer tube.
Claim 4
Dependent Claim
41 words
The tube assembly of claim 2 in which a tube-supporting element is seated within the lower end of said outer tube; said supporting element having an upwardly facing recess receiving and supporting said bottom end portion of said lower capillary section.
Claim 5
Dependent Claim
40 words
The tube assembly of claim 1 in which said upper section is provided with an outwardly projecting flange larger than said outer tube and resting upon the open upper end of said outer tube for supporting said inner tube therein.
Claim 6
Dependent Claim
19 words
The tube assembly of claim 1 in which said lower section of said inner tube is formed of glass.
Claim 7
Dependent Claim
40 words
The tube assembly of claim 5 in which said upper section of said inner tube is formed of plastic and is provided at its bottom end with a downwardly facing socket receiving the upper end of said lower capillary section.
Claim 8
Dependent Claim
98 words
A centrifuge tube assembly comprising an open-topped outer tube and an open-topped inner tube removably supported therein; said inner tube having an upper section defining an enlarged chamber and a lower section having a capillary passage communicating with said chamber; said lower section being transparent and being separable from said upper section when said inner tube is removed from said outer tube; said upper section having a body portion smaller in external diameter than the internal diameter of said outer tube; whereby, liquid in said outer tube may assume a level above the lower limits of said chamber.
Claim 9
Dependent Claim
98 words
A centrifuge tube assembly comprising an open-topped outer tube and an open-topped inner tube removably supported therein; said inner tube having an upper section defining an enlarged chamber and a lower section having a capillary passage communicating with said chamber; said lower section being transparent and being separable from said upper section when said inner tube is removed from said outer tube; said upper section having a body portion smaller in external diameter than the internal diameter of said outer tube; whereby, liquid in said outer tube may assume a level above the lower limits of said chamber.
Claim 10
Dependent Claim
30 words
The tube assembly of claim 7 in which said upper section is provided with a plurality of outwardly extending longitudinal ribs frictionally engaging the inner surface of said outer tube.
Claim 11
Dependent Claim
21 words
The tube assembly of claim 8 in which said upper section and said ribs are integrally formed of resilient plastic material.
Claim 12
Dependent Claim
17 words
The tube assembly of claim 7 in which said capillary passage is sealed at its bottom end.
Claim 13
Dependent Claim
27 words
The tube assembly of claim 7 in which said capillary passage is open at its bottom end and communicates directly with the interior of said outer tube.
Claim 14
Dependent Claim
109 words
In a method for determining the packed volumes of suspended microparticles, the steps comprising supporting a liquid containing suspended microparticles in a tube having an enlarged upper chamber and a lower capillary sEction communicating therewith, supporting said tube in a body of liquid contained in a second outer tube and, while so supported, initially centrifuging said tubes and their contents at relatively low speed to displace said microparticles from said upper chamber into said capillary section, then separating said capillary section from said upper section, and finally recentrifuging said separated capillary section and its contents at relatively high speed while the lower end of said capillary section is sealed.
Claim 15
Dependent Claim
109 words
In a method for determining the packed volumes of suspended microparticles, the steps comprising supporting a liquid containing suspended microparticles in a tube having an enlarged upper chamber and a lower capillary sEction communicating therewith, supporting said tube in a body of liquid contained in a second outer tube and, while so supported, initially centrifuging said tubes and their contents at relatively low speed to displace said microparticles from said upper chamber into said capillary section, then separating said capillary section from said upper section, and finally recentrifuging said separated capillary section and its contents at relatively high speed while the lower end of said capillary section is sealed.
Claim 16
Dependent Claim
36 words
The method of claim 12 in which there is the further step of determining the packed volume of said microparticles by measuring the length of such volume of microparticles within said capillary section following final centrifugation.
Claim 17
Dependent Claim
59 words
The method of claim 12 in which the lower end of said capillary section is in open communication with said liquid-containing outer tube during said initial centrifugation, said step of initially centrifuging said tubes and their contents being continued until substantially all microparticles except those to be measured have migrated from said capillary section into said liquid-containing outer tube.
Claim 18
Dependent Claim
30 words
The method of claim 14 in which there is the further step of sealing the lower end of said capillary section prior to final recentrifuging of said separated capillary section.
Claim 19
Independent Claim
191 words
A method for use in selectively determining the packed cell volumes of cellular components of a body fluid, comprising the steps of supporting an inner tube within an outer tube having a closed lower end and containing a liquid diluent for said body fluid; said inner tube having an upper section with an enlarged chamber therein and having an elongated lower capillary section; said capillary section communicating at its upper end with said enlarged chamber and at its lower end with the interior of said outer tube; introducing into said chamber a measured quantity of body fluid containing different cellular components; initially centrifuging the assembled inner and outer tubes until the effectively larger cellular components have migrated from said inner tube into the lower end of said outer tube and the effectively smaller cellular components are disposed substantially entirely within said capillary section; then interrupting centrifugation; separating said inner tube from said outer tube; sealing the lower end of said capillary section; separating said capillary section from said upper section; and thereafter recentrifuging only said capillary section at relatively high speed to stratify and pack the harvested cellular components contained therein.
Claim 20
Independent Claim
191 words
A method for use in selectively determining the packed cell volumes of cellular components of a body fluid, comprising the steps of supporting an inner tube within an outer tube having a closed lower end and containing a liquid diluent for said body fluid; said inner tube having an upper section with an enlarged chamber therein and having an elongated lower capillary section; said capillary section communicating at its upper end with said enlarged chamber and at its lower end with the interior of said outer tube; introducing into said chamber a measured quantity of body fluid containing different cellular components; initially centrifuging the assembled inner and outer tubes until the effectively larger cellular components have migrated from said inner tube into the lower end of said outer tube and the effectively smaller cellular components are disposed substantially entirely within said capillary section; then interrupting centrifugation; separating said inner tube from said outer tube; sealing the lower end of said capillary section; separating said capillary section from said upper section; and thereafter recentrifuging only said capillary section at relatively high speed to stratify and pack the harvested cellular components contained therein.
Claim 21
Dependent Claim
40 words
The method of claim 16 in which there is the further step of determining the packed volume of the cellular components in said capillary section by measuring the lengths of the packed cell columns of different cellular components contained therein.
Claim 22
Dependent Claim
21 words
The method of claim 16 in which said body fluid is whole blood and said effectively larger cellular components are erythrocytes.
Claim 23
Dependent Claim
17 words
The method of claim 18 in which said diluent is an aqueous fluid compatible with whole blood.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |