US3774036A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Generation of a supply of radionuclide
Assignee: GD Searle LLC
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Filing: 1972-02-23
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Granted: 1973-11-20
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Expires: 1992-02-23
Abstract
Abstract A method and apparatus for generating and maintaining an available supply of a radioactive eluate with at least a minimum level of activity. A relatively short-lived daughter radionuclide is produced by the radioactive decay of a relatively longer-lived radionuclide in a radionuclide generating chamber. The daughter radionuclide is separated from the parent radionuclide by use of an eluting solution. The resultant solution is recycled through the generator chamber to replenish and concentrate the amount of daughter radionuclide contained therein. Because a relatively large amount of eluate is produced and maintained at at least a minimum level of radioactivity, it is possible to easily meet fluctuating demands for the daughter radionuclide.
Inventors
- 👤 J Gerhart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:41
CPC Classifications
G; G21; G21G; G21G4/00; G21G4/04; G21G4/06; G21G4/08; G21G1/00; G21G1/02; G21G1/04; G21H; G21H5/00; G21G1/0005
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
84 words
A method of generating an eluate containing a desired daughter radionuclide in a closed generating system comprising passing an eluant from a source of said eluant through a generator chamber containing a parent radionuclide which spontaneously decays into a daughter radionuclide, selectively removing the daughter radionuclide in preference to said parent radionuclide to form an eluate, and recirculating the eluate produced thereby through said generator chamber in order to maintain a supply of eluate at a desired level of radioactIvity in said generating system.
Claim 2
Independent Claim
84 words
A method of generating an eluate containing a desired daughter radionuclide in a closed generating system comprising passing an eluant from a source of said eluant through a generator chamber containing a parent radionuclide which spontaneously decays into a daughter radionuclide, selectively removing the daughter radionuclide in preference to said parent radionuclide to form an eluate, and recirculating the eluate produced thereby through said generator chamber in order to maintain a supply of eluate at a desired level of radioactIvity in said generating system.
Claim 3
Dependent Claim
29 words
The method of claim 1 wherein the radioactive half-life of said parent radionuclide is at least two times as great as the radioactive half-life of said desired daughter radionuclide.
Claim 4
Dependent Claim
18 words
The method of claim 2 wherein said parent radionuclide is molybdenum-99 and said desired daughter radionuclide is technetium-99m.
Claim 5
Dependent Claim
18 words
The method of claim 3 wherein said molybdenum-99 is adsorbed on an alumina substrate in said generator chamber.
Claim 6
Dependent Claim
19 words
The method of claim 1 wherein said eluate is recirculated by pumping said eluate through said closed generating system.
Claim 7
Dependent Claim
26 words
The method of claim 1 wherein said eluate is passed through a microporous filter in said closed generating system prior to recirculation through said generator chamber.
Claim 8
Dependent Claim
37 words
The method of claim 1 wherein said eluate is passed from said generator chamber to a fluid reservoir in said closed generating system, and said eluate is passed through said reservoir for recirculation through said generator chamber.
Claim 9
Dependent Claim
16 words
The method of claim 7 further comprising continuously monitoring the radiation level in said fluid reservoir.
Claim 10
Dependent Claim
95 words
A closed radionuclide generating system for generating a relatively short-lived daughter radionuclide produced from a longer-lived parent radionuclide by spontaneous decay, comprising a source of eluant for eluting the aforesaid daughter radionuclide, a generator chamber having an inlet and an outlet with the inlet connected to said source and containing a quantity of the aforesaid parent radionuclide adsorbed on a supporting substrate, a recirculation line connected between the outlet and an inlet of said generator chamber, pumping means acting upon eluate in said recirculation line, and an eluate withdrawal port located in said recirculation line.
Claim 11
Dependent Claim
95 words
A closed radionuclide generating system for generating a relatively short-lived daughter radionuclide produced from a longer-lived parent radionuclide by spontaneous decay, comprising a source of eluant for eluting the aforesaid daughter radionuclide, a generator chamber having an inlet and an outlet with the inlet connected to said source and containing a quantity of the aforesaid parent radionuclide adsorbed on a supporting substrate, a recirculation line connected between the outlet and an inlet of said generator chamber, pumping means acting upon eluate in said recirculation line, and an eluate withdrawal port located in said recirculation line.
Claim 12
Dependent Claim
31 words
The generator system of claim 9 wherein said eluant is a saline solution and molybdenum-99 is adsorbed of the aforesaid supporting substrate, whereby technetium-99m is produced as the aforesaid daughter radionuclide.
Claim 13
Dependent Claim
37 words
The generator system of claim 9 wherein said recirculation line is formed of flexible tubing and said pumping means comprises a peristaltic pump exteriorally positioned with respect to said recirculation line and acting upon a section thereof.
Claim 14
Dependent Claim
75 words
The generator system of claim 9 further comprising a pair of valves located in said recirculation line closely adjacent to and on either side of said eluate withdrawal port to limit flow in said recirculation line to a single direction, and said pumping means comprises a syringe inserted in said withdrawal port, whereby said syringe is operable both to recirculate eluate through said generator chamber and to withdraw quantities of eluate through said withdrawal port.
Claim 15
Dependent Claim
16 words
The generating system of claim 9 further comprising a fluid reservoir located in said recirculation line.
Claim 16
Dependent Claim
33 words
The generating system of claim 13 wherein a radioactivity detecting means is positioned proximate to said fluid reservoir in order to measure the level of radioactivity in the eluate in said fluid reservoir.
Claim 17
Dependent Claim
102 words
A radionuclide generating system comprising a generator chamber having an inlet and an outlet containing a parent radionuclide that undergoes spontaneous radioactive decay to produce a daughter radionuclide, a source of eluant which selectively removes the daughter radionuclide in preference to the parent radionuclide, connected to the inlet of said generator chamber, a recirculation line onducting the solution containing the dissolved daughter radionuclide from the outlet of said generator chamber for recycling to the inlet of said generator chamber, pumping means for forcing the aforesaid solution through the recirculation line, and a withdrawal port for withdrawing solution from the radionuclide generating system.
Claim 18
Dependent Claim
102 words
A radionuclide generating system comprising a generator chamber having an inlet and an outlet containing a parent radionuclide that undergoes spontaneous radioactive decay to produce a daughter radionuclide, a source of eluant which selectively removes the daughter radionuclide in preference to the parent radionuclide, connected to the inlet of said generator chamber, a recirculation line onducting the solution containing the dissolved daughter radionuclide from the outlet of said generator chamber for recycling to the inlet of said generator chamber, pumping means for forcing the aforesaid solution through the recirculation line, and a withdrawal port for withdrawing solution from the radionuclide generating system.
Claim 19
Dependent Claim
20 words
The radionuclide generating system of claim 15 further comprising a microporous filter for removing particulate matter from the aforesaid solution.
Claim 20
Dependent Claim
35 words
The radionuclide generating system of claim 15 furTher comprising at least one valve in said recirculation line for checking flow in one direction and thereby limiting flow to the opposite direction in the recirculation line.
Claim 21
Dependent Claim
125 words
A radionuclide generating system comprising a generator chamber having opposing ends each having a fluid access connection, a charge of a granular material containing a parent radionuclide that undergoes radioactive disintegration to form a daughter radionuclide packed into the aforesaid generator chamber, a source of eluant that selectively removed the aforesaid daughter radionuclide in preference to the parent radionuclide in the generator chamber connected to one of the access connections, a recirculation line in communication with both of said access connections to recirculate to said generator chamber an eluate formed of the aforesaid daughter radionuclide in said eluant, pumping means to force said eluate through said recirculation line, and a resealable withdrawal port in communication with said recirculation line for withdrawing portions of said eluate.
Claim 22
Dependent Claim
125 words
A radionuclide generating system comprising a generator chamber having opposing ends each having a fluid access connection, a charge of a granular material containing a parent radionuclide that undergoes radioactive disintegration to form a daughter radionuclide packed into the aforesaid generator chamber, a source of eluant that selectively removed the aforesaid daughter radionuclide in preference to the parent radionuclide in the generator chamber connected to one of the access connections, a recirculation line in communication with both of said access connections to recirculate to said generator chamber an eluate formed of the aforesaid daughter radionuclide in said eluant, pumping means to force said eluate through said recirculation line, and a resealable withdrawal port in communication with said recirculation line for withdrawing portions of said eluate.
References Cited (Backward Citations)
US3576998A
Cited
US3655981A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |