Patent US2328750A successfully refreshed from Google Patents.
US4273757A
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US
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Determination of transcobalamins
Assignee: Yissum Research Development Co of Hebrew University of Jerusalem
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Filing: 1978-11-17
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Granted: 1981-06-16
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Expires: 1998-11-17
Abstract
Abstract A process and test kit for the quantitative determination of the individual and total unsaturated Vitamin B-12 binding capacities of the three transcobalamins TC-I, TC-II, and TC-III in serum. The process comprises incubating a serum sample with a solution of 57 Co Vitamin B-12, contacting the resulting mixture with a TC-II adsorbent and with a DEAE-cellulose adsorbent for TC-I and TC-III, measuring the total radioactivity adsorbed to said adsorbents, selectively desorbing TC-III from the DEAE-cellulose adsorbent by washing with a monopotassium phosphate solution of about 0.05 M and at a pH of about 4.6, measuring the individual radioactivity adsorbed to each of said adsorbents, and calculating the radioactivity that had been washed from the DEAE-cellulose adsorbent by said phosphate solution. The resulting four radioactivity values are functions of the total, TC-II, TC-I, and TC-III unsaturated Vitamin B-12 binding capacities, respectively, of the serum tested. The test kit comprises the essential elements for performing the present process.
Inventors
- 👤 Jacob Selhub
- 👤 Bracha Rachmilewitz
- 👤 Nathan Grossowicz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:42
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/82; Y; Y10; Y10S; Y10S436/00; Y10S436/807; Y10S436/808
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
256 words
A method for the quantitative determination of the individual and total unsaturated Vitamin B-12 binding capacities of the three transcobalamins TC-I, TC-II, and TC-III in serum, which method comprises the steps of incubating a predetermined quantity of serum with a solution of 57 Co Vitamin B-12 whereby the unsaturated Vitamin B-12 binding sites on the transcobalamins in said quantity of serum become occupied by the radioactive Vitamin B-12; contacting the resulting mixture with (a) a TC-II adsorbent whereby the TC-II from said quantity of serum becomes adsorbed thereto, and (b) a DEAE-cellulose adsorbent whereby the TC-I and TC-III from said quantity of serum becomes adsorbed thereto; washing away from said adsorbents the 57 Co Vitamin B-12 not bound to any of the transcobalamins; measuring the total radioactivity of said adsorbents, which radioactivity is a function of the total unsaturated Vitamin B-12 binding capacity of the serum tested; selectively desorbing TC-III from said DEAE-cellulose by washing with a monopotassium phosphate solution of about 0.05 M and at a pH of about 4.6; measuring the individual radioactivity of said adsorbents, which radioactivity of said TC-II adsorbent is a function of the TC-II unsaturated Vitamin B-12 binding capacity of the serum tested and that of said DEAE-cellulose adsorbent is a function of the TC-I unsaturated Vitamin B-12 binding capacity of the serum tested; and calculating the difference in radioactivity of said total radioactivity measurement and the sum of said individual radioactivity measurements, which difference is a function of the TC-III unsaturated Vitamin B-12 binding capacity of the serum tested.
Claim 2
Independent Claim
256 words
A method for the quantitative determination of the individual and total unsaturated Vitamin B-12 binding capacities of the three transcobalamins TC-I, TC-II, and TC-III in serum, which method comprises the steps of incubating a predetermined quantity of serum with a solution of 57 Co Vitamin B-12 whereby the unsaturated Vitamin B-12 binding sites on the transcobalamins in said quantity of serum become occupied by the radioactive Vitamin B-12; contacting the resulting mixture with (a) a TC-II adsorbent whereby the TC-II from said quantity of serum becomes adsorbed thereto, and (b) a DEAE-cellulose adsorbent whereby the TC-I and TC-III from said quantity of serum becomes adsorbed thereto; washing away from said adsorbents the 57 Co Vitamin B-12 not bound to any of the transcobalamins; measuring the total radioactivity of said adsorbents, which radioactivity is a function of the total unsaturated Vitamin B-12 binding capacity of the serum tested; selectively desorbing TC-III from said DEAE-cellulose by washing with a monopotassium phosphate solution of about 0.05 M and at a pH of about 4.6; measuring the individual radioactivity of said adsorbents, which radioactivity of said TC-II adsorbent is a function of the TC-II unsaturated Vitamin B-12 binding capacity of the serum tested and that of said DEAE-cellulose adsorbent is a function of the TC-I unsaturated Vitamin B-12 binding capacity of the serum tested; and calculating the difference in radioactivity of said total radioactivity measurement and the sum of said individual radioactivity measurements, which difference is a function of the TC-III unsaturated Vitamin B-12 binding capacity of the serum tested.
Claim 3
Dependent Claim
65 words
The method of claim 1 wherein the radioactivity values corresponding to the total TC-I, TC-II, and TC-III unsaturated Vitamin B-12 binding capacities of the serum tested are converted to Vitamin B-12 concentration values by comparison of said total radioactivity measurement to the radioactivity of a solution of 57 Co Vitamin B-12 of known concentration and calculating the fractions thereof attributable to TC-I, TC-II, and TC-III.
Claim 4
Dependent Claim
16 words
The method of claim 1 wherein said TC-II adsorbent is made of a charged cellulose material.
Claim 5
Dependent Claim
14 words
The method of claim 3 wherein said TC-II adsorbent is a cellulose nitrate filter.
Claim 6
Dependent Claim
15 words
The method of claim 1 wherein said TC-II adsorbent is made of a silica material.
Claim 7
Dependent Claim
13 words
The method of claim 5 wherein said TC-II adsorbent is granular silica gel.
Claim 8
Dependent Claim
16 words
The method of claim 1 wherein said DEAE-cellulose adsorbent is in the form of a filter.
Claim 9
Dependent Claim
14 words
The method of claim 1 wherein said DEAE-cellulose adsorbent is in a granular form.
Claim 10
Dependent Claim
22 words
The method of claim 1 wherein said adsorbents are arranged as a stack of a cellulose nitrate filter and a DEAE-cellulose filter.
Claim 11
Dependent Claim
26 words
The method of claim 1 wherein said adsorbents are arranged as a stackable pair of columns, one containing granular silica gel and the other granular DEAE-cellulose.
Claim 12
Dependent Claim
66 words
A test kit for the quantitative determination of the individual and total unsaturated Vitamin B-12 binding capacity of the three transcobalamins TC-I, TC-II, and TC-III in serum, comprising, in a packaged combination, a container of a solution of 57 Co Vitamin B-12; a TC-II adsorbent; a DEAE-cellulose adsorbent; and a container of monopotassium phosphate solution of about 0.05 M and at a pH of about 4.6.
Claim 13
Dependent Claim
66 words
A test kit for the quantitative determination of the individual and total unsaturated Vitamin B-12 binding capacity of the three transcobalamins TC-I, TC-II, and TC-III in serum, comprising, in a packaged combination, a container of a solution of 57 Co Vitamin B-12; a TC-II adsorbent; a DEAE-cellulose adsorbent; and a container of monopotassium phosphate solution of about 0.05 M and at a pH of about 4.6.
Claim 14
Dependent Claim
17 words
The test kit of claim 11 wherein said TC-II adsorbent is made of a charged cellulose material.
Claim 15
Dependent Claim
15 words
The test kit of claim 12 wherein said TC-II adsorbent is a cellulose nitrate filter.
Claim 16
Dependent Claim
16 words
The test kit of claim 11 wherein said TC-II adsorbent is made of a silica material.
Claim 17
Dependent Claim
14 words
The test kit of claim 14 wherein said TC-II adsorbent is granular silica gel.
Claim 18
Dependent Claim
17 words
The test kit of claim 11 wherein said DEAE-cellulose adsorbent is in the form of a filter.
Claim 19
Dependent Claim
15 words
The test kit of claim 11 wherein said DEAE-cellulose adsorbent is in a granular form.
Claim 20
Dependent Claim
23 words
The test kit of claim 11 wherein said adsorbents are arranged as a stack of a cellulose nitrate filter and a DEAE-cellulose filter.
Claim 21
Dependent Claim
25 words
The test kit of claim 18 which additionally comprises a container of borate solution of about 0.1 M and at a pH of about 8.5.
Claim 22
Dependent Claim
27 words
The test kit of claim 11 wherein said adsorbents are arranged as a stackable pair of columns, one containing granular silica gel and the other granular DEAE-cellulose.
Claim 23
Dependent Claim
25 words
The test kit of claim 20 which additionally comprises a container of phosphate solution of about 0.02 M and at a pH of about 6.4.
Claim 24
Dependent Claim
20 words
The test kit of claim 11 wherein the 57 Co Vitamin B-12 is of an activity of from 135-200 μCi/μg.
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) | 1984-06-15 | 1984-12-15 | 1985-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-15 | 1988-12-15 | 1989-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-15 | 1992-12-15 | 1993-06-16 | $7700.00 | Window Closed / Lapsed |