US4382813A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Encapsulation by entrapment within starch adduct matrix
Assignee: United States Department of Agriculture
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Filing: 1980-10-30
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Granted: 1983-05-10
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Expires: 2000-10-30
Abstract
Abstract Water-insoluble chemical biological agents to be encapsulated are dispersed in an aqueous paste of a starch-containing material alkoxide. Subsequent addition of selected water-soluble alkali earth metal cations insolubilize the paste, thereby entrapping the agents in a protective matrix. Encapsulation of biologically active compositions provides a shield against hostile environments, improves safety in handling, and slows the release of such compounds to the surrounding medium. Highly volatile liquids are protected against losses by evaporation. Encapsulation also provides protection against decomposition from exposure to ultraviolet light.
Inventors
- 👤 Baruch S. Shasha
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:59
CPC Classifications
B; B01; B01J; B01J13/00; B01J13/02; B01J13/06; B01J13/08; A; A01; A01N; A01N25/00; A01N25/26
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
124 words
A method of encapsulating a water-insoluble, chemical biological agent comprising the steps of: a. preparing a dispersion of a suitable chemical biological agent in a matrix-forming material comprising an aqueous paste of a starchcontaining material (SCM) alkoxide, wherein said paste has a solids concentration of SCM alkoxide of from about 6-20%, and wherein the relative amount of said SCM alkoxide with respect to said biological agent is sufficient to entrap said agent within a matrix of said SCM; b. reacting from a single phase said SCM alkoxide with a suitable bivalent cation selected from the group consisting of calcium, barium, and strontium to form a continuous insolubilized matrix having entrapped therein discontinuous domains of said agent; and c. recovering said entrapped chemical biological agent.
Claim 2
Independent Claim
124 words
A method of encapsulating a water-insoluble, chemical biological agent comprising the steps of: a. preparing a dispersion of a suitable chemical biological agent in a matrix-forming material comprising an aqueous paste of a starchcontaining material (SCM) alkoxide, wherein said paste has a solids concentration of SCM alkoxide of from about 6-20%, and wherein the relative amount of said SCM alkoxide with respect to said biological agent is sufficient to entrap said agent within a matrix of said SCM; b. reacting from a single phase said SCM alkoxide with a suitable bivalent cation selected from the group consisting of calcium, barium, and strontium to form a continuous insolubilized matrix having entrapped therein discontinuous domains of said agent; and c. recovering said entrapped chemical biological agent.
Claim 3
Dependent Claim
42 words
A method as described in claim 1 wherein the suitable chemical biological agent is a water-insoluble herbicide, insecticide, fungicide, nematocide, bactericide, rodenticide, molluscide, acaricide, larvacide, fumigant, animal repellant, insect repellant, plant growth regulator, fertilizer, pheromone, sex lure, flavor composition, or odor composition.
Claim 4
Dependent Claim
58 words
A method as described in claim 1 wherein the suitable chemical biological agent is S-ethyl dipropylcarbamothioate, S-propyl dipropylcarbamothioate, S-propyl butylethylcarbamothioate, S-ethyl cyclohexylethylcarbamothioate, S-ethyl bis(2-methylpropyl)-carbamothioate, S-ethyl hexahydro-1-H-azepine-1-carbothioate, S-(2,3,3-trichloro-2-propenyl)bis(1-methylethyl)carbamothioate, 2,6-dinitro-N,N-dipropyl-4-(trifluoromethyl)benzenamine, N-butyl-N-ethyl-2,6-dinitro-4-(trifluoromethyl) benzenamine, N-(cyclopropylmethyl)-2,6-dinitro-N-propyl-4-(trifluoromethyl) benzenamine, 2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide, 2-chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl) acetamide, 2,4-dichlorophenoxyacetic acid, propylene glycol butyl ether, 2,6-dichlorobenzonitrile, 3a,4,7,7a-tetrahydro-2-[(trichloromethyl)thio]-1-H-isoindole-1,3(2H)-dione, 3a,4,7,7a-tetrahydro-2-[(1,1,2,2-tetrachloroethyl) thio]-1-H-isoindole-1,3(2H)-dione, N-[[(4-chlorophenyl) amino] carbonyl]-2,6-difluorobenzamide, 1,1'-(2,2,2-trichloroethylidene) bis(4-chlorobenzene), O,O-diethyl O-6-methyl-2-(1-methylethyl)-4-pyrimidinyl phosphorothioate, O-ethyl-S-phenyl ethylphosphorodithioate, or 1,2-dibromo-3-chloropropane.
Claim 5
Dependent Claim
27 words
A method as described in claim 1 wherein said SCM alkoxide is the sodium or potassium salt of cereal starch, potato starch, cereal flour, or potato flour.
Claim 6
Dependent Claim
20 words
A method as described in claim 1 wherein said SCM alkoxide is the sodium or potassium salt of acid-modified starch.
Claim 7
Dependent Claim
13 words
A method as described in claim 1 wherein said bivalent cation is calcium.
Claim 8
Dependent Claim
11 words
A composition of matter produced by the process of claim 1.
Claim 9
Dependent Claim
11 words
A composition of matter produced by the process of claim 2.
Claim 10
Dependent Claim
11 words
A composition of matter produced by the process of claim 3.
Claim 11
Dependent Claim
11 words
A composition of matter produced by the process of claim 4.
Claim 12
Dependent Claim
11 words
A composition of matter produced by the process of claim 6.
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) | 1986-05-09 | 1986-11-08 | 1987-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-09 | 1990-11-08 | 1991-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-09 | 1994-11-08 | 1995-05-10 | $7700.00 | Window Closed / Lapsed |