US3275416A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and device for separating barbituric acid derivatives from biological samples, and for analyzing same
Assignee: Pfizer Health AB
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Filing: 1962-12-10
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Granted: 1966-09-27
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Expires: 1982-12-10
Abstract
No abstract record available.
Inventors
- 👤 Stig G B Zaar
- 👤 Bo G Wallenius
- 👤 Lausing Endel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:54
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/94; G01N33/948; Y; Y10; Y10T; Y10T436/00; Y10T436/14; Y10T436/145555; Y10T436/147777; Y10T436/17; Y10T436/173845
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
103 words
A METHOD FOR SEPARATING BARBITURIC ACID DERIVATIVES FROM CONSTITUENTS PRESENT IN A SAMPLE OF A BIOLOGICAL LIQUID FOR ANALYTICAL PURPOSES COMPRISING: (A) PLACING THE SAMPLE ON A FIRST POROUS CARRIER, (B) THEREAFTER CONTACTING THE POROUS CARRIER AND DEPOSITED SAMPLE WITH CHLOROFORM WHICH SELECTIVELY DISSOLVES THE BARBITARIC ACID DERIVATIVE FROM THE SAMPLE, (C) PASSING SAID CHLOROFORM SOLUTION OF THE BARBITURIC ACID DERIVATIVE INTO CONTACT WITH A SECOND POROUS CARRIER, (D) SAID SECOND POROUS CARRIER CONTAINING A MERCURIC SALT THAT REACTS WITH THE BARBITURIC ACID DERIVATIVE AND FORMS A COMPLEX THEREWITH, AND (E) THEREAFTER CONTACTING SAID COMPLEX OF MERCURY AND BARBITURIC ACID DERIVATIVE WITH DITHIZONE.
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) | 1969-09-26 | 1970-03-28 | 1970-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-26 | 1974-03-28 | 1974-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-26 | 1978-03-28 | 1978-09-27 | $7700.00 | Window Closed / Lapsed |