Patent US4264471A successfully refreshed from Google Patents.
US4264471A
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Serum and plasma clarification process
Assignee: Dade Behring Inc
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Filing: 1979-06-04
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Granted: 1981-04-28
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Expires: 1999-06-04
Abstract
Abstract A process for obtaining delipified human serum or plasma of low turbidity, and therefore decreased light scattering, is provided. This process comprises the simultaneous steps of deionization and pH adjustment of the serum or plasma to near the isoelectric point of lipoproteins commonly found in sera and results in the precipitation of much of the lipoprotein fraction. The process is carried out utilizing a mixed anion-cation exchange resin. The sera so obtained can be used as base material or a special diluent for verifying analytical information obtained in clinical analyses.
Inventors
- 👤 Anglis R. Briggs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:21
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/96; G01N2496/00; G01N2496/05; Y; Y10; Y10S; Y10S530/00; Y10S530/827; Y10S530/829; Y10S530/83; Y10T; Y10T436/00; Y10T436/10; Y10T436/104165; Y10T436/106664; Y10T436/108331
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
102 words
A process for preparing substantially completely delipified animal serum comprising the steps of: (A) rapid mixing of serum with a mixed anion-cation ion exchange resin, wherein the resin is present in a quantity sufficient to remove substantially all electrolytes from the serum and wherein there is sufficient excess of cation resin over anion resin to reduce the pH of the serum to 5.2±0.3; (B) continued mixing until the pH reaches a value of 5.2±0.3; and (C) separation of the supernatant serum resulting after mixing is discontinued and the resin and a precipitate formed during steps (A) and (B) are allowed to settle.
Claim 2
Dependent Claim
102 words
A process for preparing substantially completely delipified animal serum comprising the steps of: (A) rapid mixing of serum with a mixed anion-cation ion exchange resin, wherein the resin is present in a quantity sufficient to remove substantially all electrolytes from the serum and wherein there is sufficient excess of cation resin over anion resin to reduce the pH of the serum to 5.2±0.3; (B) continued mixing until the pH reaches a value of 5.2±0.3; and (C) separation of the supernatant serum resulting after mixing is discontinued and the resin and a precipitate formed during steps (A) and (B) are allowed to settle.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein the animal serum is human serum.
Claim 4
Dependent Claim
25 words
The process of claim 1 wherein the anion exchange resin is a strong base resin and the cation exchange resin is a strong acid resin.
Claim 5
Dependent Claim
25 words
The process of claim 1 wherein the anion exchange resin is a weak base resin and the cation exchange resin is a weak acid resin.
Claim 6
Dependent Claim
21 words
The process of claim 1 wherein after step (C) the pH of said serum is adjusted to a pH of 7.3±0.3.
Claim 7
Dependent Claim
12 words
The process of claim 5 wherein the pH is adjusted with 2-amino-2-hydroxymethyl-1,3-propanediol.
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) | 1984-04-27 | 1984-10-27 | 1985-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-27 | 1988-10-27 | 1989-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-27 | 1992-10-27 | 1993-04-28 | $7700.00 | Window Closed / Lapsed |