Patent US2932704A successfully refreshed from Google Patents.
Patent US4257771A successfully refreshed from Google Patents.
US4257771A
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Process for measuring lecithin concentration in biological fluids
Assignee: Individual
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Filing: 1979-04-30
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Granted: 1981-03-24
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Expires: 1999-04-30
Abstract
Abstract A process for determining lecithin concentration in biological fluids such as blood and amniotic fluids including the steps of separating the lecithin from the fluid and isolating the separated lecithin from similar phospholipids by column chromatography. The separated lecithin is then hydrolyzed and formed into chromogens. The evaluation of the concentration of the lecithin is done by spectrophotometric measurement.
Inventors
- 👤 Hugh Yee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:08
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/92; Y; Y10; Y10T; Y10T436/00; Y10T436/16; Y10T436/163333; Y10T436/17; Y10T436/173845
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
65 words
A process for determining the lecithin concentration in a biological fluid, comprising the steps of: (a) separating the lecithin from the fluid; (b) isolating the separated lecithin from similar phospholipids by passing the extract through a column containing a specific adsorbent material; (c) hydrolyzing the separated lecithin; (d) forming the separated lecithin into chromogens; and (e) evaluating the concentration of the lecithin by spectrophotometric measurement.
Claim 2
Dependent Claim
65 words
A process for determining the lecithin concentration in a biological fluid, comprising the steps of: (a) separating the lecithin from the fluid; (b) isolating the separated lecithin from similar phospholipids by passing the extract through a column containing a specific adsorbent material; (c) hydrolyzing the separated lecithin; (d) forming the separated lecithin into chromogens; and (e) evaluating the concentration of the lecithin by spectrophotometric measurement.
Claim 3
Dependent Claim
19 words
The process defined in claim 1 wherein the step of separating the lecithin is accomplished by extraction with chloroform-methanol.
Claim 4
Dependent Claim
20 words
The process defined in claim 1 wherein the step of separating the lecithin is accomplished by extraction with ethanol-ethyl ether.
Claim 5
Dependent Claim
30 words
The process defined in claim 1 wherein the step of hydrolyzing the separated lecithin is performed by a chemical mixture of periodic acid and ethanol in a sulfuric acid solution.
Claim 6
Dependent Claim
31 words
The process defined in claim 1 wherein the step of forming the separated lecithin into chromogens is performed by reaction of the liberated phosphate derived from the lecithin with ammonium molybdate.
Claim 7
Dependent Claim
25 words
The process defined in claim 5 wherein after the chromogen forming there is included the further step of reduction with stannous chloride and hydrazine sulfate.
Claim 8
Dependent Claim
37 words
The process defined in claim 1 wherein the evaluating of the concentration of the lecithin is determined by comparison of the absorbance values of the lecithin sample being measured with those of lecithin standards of known concentrations.
Claim 9
Dependent Claim
17 words
The process defined in claim 1 including the further step of diluting the hydrolyzed lecithin with water.
Claim 10
Dependent Claim
19 words
The process defined in claim 1 including washing the column with methanol to complete removal of the separated lecithin.
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) | 1984-03-23 | 1984-09-22 | 1985-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-23 | 1988-09-22 | 1989-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-23 | 1992-09-22 | 1993-03-24 | $7700.00 | Window Closed / Lapsed |