US4093381A
Expired / Lapsed
US
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Method for assaying endotoxins
Assignee: RAF-TAN Inc
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Filing: 1976-11-29
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Granted: 1978-06-06
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Expires: 1996-11-29
Abstract
Abstract A new convenient and more reliable spectrophotometric method for assaying endotoxins at levels as low as 10 ppb. Five different solutions of endotoxins, E. coli 0127:B8, E. coli 055:B5, S. abortus equi, S. enteritidis and S. flexneri were examined and each exhibited an absorption maximum of 259 mm.
Inventors
- 👤 Narbik A. Karamian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:25
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/52; G01N2400/00; G01N2400/10; G01N2400/50; Y; Y10; Y10T; Y10T436/00; Y10T436/14; Y10T436/142222; Y10T436/143333
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
94 words
A method for assaying endotoxins in aqueous liquids comprising the following steps: a. introducing a known volume of an aqueous liquid containing lipopolysaccharide endotoxins of the bacteria selected from the group consisting of E. coli 0127:B8, E. coli 055:B5, S. abortus equi, S. enteritidis and S. flexneri b. maintaining the temperature of the sample in the cell at between 20° and 30° C, c. passing ultra-violet radiation of a wave length between 200 and 800 nm thru said liquid sample in the cell, d. measuring the absorbance of the detecting radiation at 259 nm.
Claim 2
Independent Claim
94 words
A method for assaying endotoxins in aqueous liquids comprising the following steps: a. introducing a known volume of an aqueous liquid containing lipopolysaccharide endotoxins of the bacteria selected from the group consisting of E. coli 0127:B8, E. coli 055:B5, S. abortus equi, S. enteritidis and S. flexneri b. maintaining the temperature of the sample in the cell at between 20° and 30° C, c. passing ultra-violet radiation of a wave length between 200 and 800 nm thru said liquid sample in the cell, d. measuring the absorbance of the detecting radiation at 259 nm.
Claim 3
Dependent Claim
23 words
The method according to claim 1 wherein the endotoxins are present in the solution in a connection of between 10 and 10,000 ppb.
Claim 4
Dependent Claim
34 words
The method according to claim 1 wherein, in addition to detecting radiation, reference radiation is passed through the liquid in the cell, said reference radiation being of a wavelength weakly absorbed by the liquid.
References Cited (Backward Citations)
US3327119A
Cited
US3944391A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-06-05 | 1981-12-05 | 1982-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-06-05 | 1985-12-05 | 1986-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-06-05 | 1989-12-05 | 1990-06-06 | $7700.00 | Window Closed / Lapsed |