Patent US3801280A successfully refreshed from Google Patents.
US3801280A
Expired / Lapsed
US
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Solubility-dissolution test apparatus and method
Assignee: Pharmacia and Upjohn Co
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Filing: 1971-11-11
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Granted: 1974-04-02
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Expires: 1991-11-11
Abstract
Abstract Apparatus and method for measuring the dissolution rate of a solid material. A container is provided for a solvent and a preforated chamber for the solid material is positioned within said container. A rotatable hollow filter is also located within said container and means are provided for effecting rotation thereof. Said rotation performs the double function of keeping the filter screen clear of solid particles and agitating the solvent. Pumping means draw the material-containing solution from within said hollow filter and convey it to suitable means for measuring the concentration of solute in the solvent, such as spectrographic measuring means. The material-containing solution may then be returned to said container.
Inventors
- 👤 A Shah
- 👤 C Peot
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:35
CPC Classifications
G; G01; G01N; G01N13/00; G01N2013/006; G01N35/00; G01N2035/00178; G01N2035/00188; G01N2035/00198; G01N33/00; G01N33/15
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
51 words
The device of claim 1 wherein said filter is substantially cylindrical and rotates on its axis of symmetry and includes means defining a filter element which presents substantially circular transverse cross-sections throughout its axial length for frictionally engaging said liquid and thereby circulating said liquid smoothly through said sample holding means.
Claim 2
Dependent Claim
60 words
The device of claim 1 wherein said filter is substantially centrally located in said container to substantially uniformly circulate liquid around said container and the means holding the sample in a perforated basket positioned off center within said container at a point between the rotatable filter unit and the wall of the container to facilitate laminar flow of liquid therethrough.
Claim 3
Dependent Claim
54 words
The device of claim 1 including analyzing means for continuously monitoring and indicating the solute content of a solution passing therethrough and solvent conducting means for receiving solvent from within said rotatable filter through said withdrawal means during filter rotation, conducting same to and through said analyzing means and returning same to said container.
Claim 4
Dependent Claim
12 words
The device of claim 4 wherein said analyzing means is a spectrophotometer.
Claim 5
Dependent Claim
20 words
The device of claim 1 including valve means for withdrawing material-containing solvent from said withdrawal means for batch testing thereof.
Claim 6
Dependent Claim
72 words
The device of claim 1 wherein said filter includes a supporting rod having a withdrawal passageway therein, a generally cylindrically shaped filter element surrounding said rod and hollow core means interposed radially between said filter element and rod and supporting said filter, said core means being rotatable on and with respect to said rod, and passageway means for conducting liquid from said filter element to said withdrawal passageway within said supporting rod.
Claim 7
Dependent Claim
85 words
The device of claim 1 including a test sample comprising at least one solid body, said holding means being porous to permit liquid circulation past said sample, and wherein said filter is of circular cross-section and is supported for rotation about its axis of symmetry and said means effecting rotation includes a motor having a rangE of selectable speeds including speeds at which filter rotation imparts a gentle laminar agitation to said liquid to cause same to flow evenly and smoothly past said test sample.
Claim 8
Dependent Claim
49 words
The device of claim 1 wherein said means holding said test sample is fixedly located in said container but vertically adjustable with respect to said container and said rotatable filter and holds said sample fixed with respect to said container to avoid abrasion thereof and shedding of particles thereby.
Claim 9
Dependent Claim
49 words
The device of claim 1 including means connectable to a supply of fresh solvent for supplying fresh solvent to the container at a desired rate corresponding to the withdrawal rate of said withdrawal means and wherein in vitro testing can be carried out to simulate in vivo sample activity.
Claim 10
Dependent Claim
105 words
The device of claim 1 including a cover on said container, said withdrawal means including a sleeve extending substantially centrally through said cover and longitudinally adjustably fixed thereto for rotatably supporting said filter with respect thereto in said container, means defining an enlarged hole off center in said cover for addition to and removal from said container of said liquid and sample holding means without disturbing said cover and filter, a disk closingly engageable with said hole and vertically adjustably supporting said sample holding means in pendant relation therewith for fixedly locating said sample holding means with respect to the rotational axis of said filter.
Claim 11
Dependent Claim
83 words
The device of claim 1 including a cover on said container and having an opening therethrough, said means holding a test sample comprising a disk registerable with said opening for closing same, an elongate member pendant from said disk, and a perforate test sample receptacle secured to said elongate member remote from said disk, said opening in said cover being sized for free passage of said elongate member and sample receptacle therethrough into said container and for support of disk by said cover.
Claim 12
Dependent Claim
69 words
The device of claim 12 wherein the peripheral edges of said opening in said cover and of said disk are respectively provided with upwardly facing and downwardly facing beveled edges which are opposed for axially and radially locating said disk on said cover and including means adjustably axially locking said elongate member to said disk to govern the height of which the test sample is supported in said container.
Claim 13
Independent Claim
142 words
A method for initiating solubility-dissolution testing: filling a container to a desired level with liquid comprising a solvent; immersing a closed hollow filter within said liquid in said container so that liquid enters the filter and imparting a laminar circulation to said liquid by rotating said filter with respect to said container; conducting liquid from within said filter through an analyzer device; returning liquid consisting at least in part of solvent to said container; and thereafter inserting into and substantially fixedly locating within said container, in contact with said circulating liquid therein and adjacent said rotating filter, a test sample to be dissolved in said liquid; whereby at least the major testing conditions including liquid movement are established before introduction of the sample into the liquid and such introduction and fixed location of said sample into said circulating liquid initiates the test.
Claim 14
Dependent Claim
91 words
The device of claim 7 in which said hollow core means has a longitudinal opening, said rod being rotatably received in said longitudinal opening, said passageway means including a transverse passageway extending from said filter to said opening in said core means, and further including; means defining a spiral groove between said core means and rod and extending from said transverse passageway along said rod into communication with said withdrawal passage in said rod for flowing filtered liquid therethrough and lubricating the relatively rotating portions of said core means and rod.
Claim 15
Dependent Claim
67 words
The device of claim 15 in whiCh said longitudinal opening includes one radial enlargement at one end of said core means, said rod including a head in said one enlargement, and bearing on an end of said one enlargement to define a thrust bearing preventing movement of said core means off said rod, said withdrawal passage of said rod and spiral groove communicating through said one enlargement.
Claim 16
Dependent Claim
53 words
The device defined in claim 16 in which said one enlargement is internally threaded, said filter further including a base fixedly carrying a permanent magnet adapted to rotate said filter, said base abutting said core means and having an extension received in and threadedly engaging in said one enlargement of said core means.
Claim 17
Dependent Claim
95 words
The device of claim 17 in which said core means comprises a cylindrical core, a top on said cylindrical core extending radially outwardly thereof, said base abutting and extending radially beyond the bottom of said core, said base and top defining opposed annular grooves extending radially outboard of said core, annular cushion means in said annular grooves, said filter element being cylindrical and extending between said cushion means in close radial adjacency with said core, said core and filter element defining an annular liquid flow space therebetween communicating at one end with said transverse passageway.
Claim 18
Dependent Claim
52 words
The device of claim 15 in which said longitudinal opening includes an upper enlargement at the upper end of said core means, said upper enlargement communicating between said transverse passageway and said spiral groove, a seal recessed in the end of said upper enlargement in surrounding and sealing relation with said rod.
Claim 19
Dependent Claim
105 words
The device of claim 19 in which said longitudinal opening includes a lower enlargement at the lower end of said core means, said rod including a head in said lower enlargement and bearing on said core means, said rod supporting said core means for rotation thereon between said seal and head wherein filtered liquid flow through said spiral groove between said enlargements provides lubrication between said rod and rod head and the adjacent surfaces of said seal, longitudinal opening, and lower enlargement, said filter further including a base and means securing said base to the bottom of said core means for closing said lower enlargement.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |