US4581141A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dialysis material and method for removing uremic substances
Assignee: Hemocleanse Inc
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Filing: 1983-04-05
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Granted: 1986-04-08
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Expires: 2003-04-05
Abstract
Abstract Compositions for removing uremic substances during hemodialysis comprising an aqueous slurry containing charcoal, a highly calcium-loaded zeolite cation exchanger, purified urease (which may be bound to a portion of the zeolite, a suspending agent, and optionally an aliphatic carboxylic acid resin in the H+ form, and a hemodialysis method employing such compositions.
Inventors
- 👤 Stephen R. Ash
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:47
CPC Classifications
A; A61; A61M; A61M1/00; A61M1/36; A61M1/3687; A61M1/14; A61M1/16; A61M1/1694; A61M1/1696; B; B01; B01D; B01D61/00; B01D61/24; B01D61/30; A61M1/26; A61M1/28; A61M1/287; B01D2311/00; B01D2311/06
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
42 words
A composition for use in dialysis comprising a surface adsorptive substance capable of adsorption of uremic substances, water, a suspending agent, urease, a calcium-loaded cation exchanger, an aliphatic carboxylic acid resin in the H + form, and a metabolizable organic acid buffer.
Claim 2
Dependent Claim
42 words
A composition for use in dialysis comprising a surface adsorptive substance capable of adsorption of uremic substances, water, a suspending agent, urease, a calcium-loaded cation exchanger, an aliphatic carboxylic acid resin in the H + form, and a metabolizable organic acid buffer.
Claim 3
Dependent Claim
15 words
A composition according to claim 1 in which the metabolizable organic acid is diethylmalonic acid.
Claim 4
Dependent Claim
20 words
A composition according to claim 1 in which the aliphatic carboxylic acid resin is polymerized methacrylic acid cross-linked with divinylbenzene.
Claim 5
Dependent Claim
15 words
A composition according to claim 1 in which the cation exchanger is a calcium-loaded zeolite.
Claim 6
Dependent Claim
14 words
The composition of claim 4 in which the zeolite is about 50% calcium loaded.
Claim 7
Dependent Claim
27 words
A composition according to claim 1 in which the cation exchanger is a mixture of zeolites capable of furnishing from 2.8-3.2 meq. of calcium ions per gram.
Claim 8
Dependent Claim
13 words
A composition according to claim 1 in which the suspending agent is methylcellulose.
Claim 9
Dependent Claim
15 words
A composition according to claim 1 in which the surface adsorptive substance is activated charcoal.
Claim 10
Dependent Claim
22 words
A composition according to claim 1 in which the total weight of solids in the suspension is not more than 3 g/l.
Claim 11
Dependent Claim
31 words
A composition according to claim 1 in which the cation exchanger is a zeolite or mixture of zeolites and the urease is bound to a portion of one of the zeolites.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-07 | 1989-10-07 | 1990-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-07 | 1993-10-07 | 1994-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-07 | 1997-10-07 | 1998-04-08 | $7700.00 | Window Closed / Lapsed |