US5298262A
Expired / Lapsed
US
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Use of ionic cloud point modifiers to prevent particle aggregation during sterilization
Assignee: PARTICULATE PROSPECTS CORP
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Filing: 1992-12-04
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Granted: 1994-03-29
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Expires: 2012-12-04
Abstract
Abstract This invention discloses a composition comprised of nanoparticles having a surface modifier adsorbed on the surface thereof and an anionic or cationic surfactant as a cloud point modifier associated therewith, which cloud point modifier is present in an amount sufficient to increase the cloud point of the surface modifier. A preferred surface modifier is tyloxapol. Preferred anionic surfactants are dioctylsulfonesuccinate, sodium dodecyl sulfate and sodium oleate. Preferred cationic surfactants are dodecyltrimethylammonium bromide and cetrimide tetradecyl ammonium bromide. This invention further discloses a method of making nanoparticles having a surface modifier adsorbed on the surface and an anionic or cationic surfactant as a cloud point modifier associated therewith, comprised of contacting said nanoparticles with the cloud point modifier for a time and under conditions sufficient to increase the cloud point of the surface modifier.
Inventors
- 👤 George C. Na
- 👤 Natarajan Rajagopalan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:30
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/14; A61K9/141; A61K9/145; A61K49/00; A61K49/04; A61K49/0433; A61K49/0447; A61K49/0476; A61K49/0485; A61K49/049; A61K9/146; B; B82; B82Y; B82Y5/00; Y; Y10; Y10S; Y10S977/00; Y10S977/70; Y10S977/773; Y10S977/84; Y10S977/842; Y10S977/847
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
87 words
A compound comprised of nanoparticles consisting essentially of a crystalline diagnostic or therapeutic agent and a non-crosslinked nonionic surfactant adsorbed on the surface thereof and an anionic or cationic cloud point modifier associated therewith, which cloud point modifier is present in an amount of 0.005-20% by weight based on the total weight of the composition and sufficient to increase the cloud point of the surface modifier, wherein said nanoparticles are resistant to particle size growth when said composition is heat sterilized at 121° C. for 15 minutes.
Claim 2
Dependent Claim
87 words
A compound comprised of nanoparticles consisting essentially of a crystalline diagnostic or therapeutic agent and a non-crosslinked nonionic surfactant adsorbed on the surface thereof and an anionic or cationic cloud point modifier associated therewith, which cloud point modifier is present in an amount of 0.005-20% by weight based on the total weight of the composition and sufficient to increase the cloud point of the surface modifier, wherein said nanoparticles are resistant to particle size growth when said composition is heat sterilized at 121° C. for 15 minutes.
Claim 3
Dependent Claim
12 words
The composition of claim 1 wherein said nanoparticles contain a diagnostic agent.
Claim 4
Dependent Claim
11 words
The composition of claim 1 wherein said surface modifier is tyloxapol.
Claim 5
Dependent Claim
12 words
The composition of claim 2 wherein said diagnostic agent is ethyl 3,5-diacetoamido-2,4,6-triiodobenzoate.
Claim 6
Dependent Claim
26 words
The composition of claim 1 wherein said anionic cloud point modifier is selected from the group cosisting of sodium dodecyl sulfate, dioctylsulfosuccinate, taurodeoxycholate and sodium oleate.
Claim 7
Dependent Claim
25 words
The composition of claim 1 wherein said cationic cloud point modifier is selected from the group consisting of dodecyltrimethylammonium bromide and tetradecyl trimethyl ammonium bromide.
Claim 8
Dependent Claim
11 words
The composition of claim 1 further comprising an isotonicity maintaining compound.
Claim 9
Dependent Claim
19 words
The composition of claim 7 wherein said maintaining compound is selected from the group consisting of mannitol or dextrose.
Claim 10
Dependent Claim
12 words
The composition of claim 1 further comprising a pH value maintaining compound.
Claim 11
Dependent Claim
14 words
The composition of claim 9 wherein said pH value maintaining compound is sodium phosphate.
Claim 12
Dependent Claim
26 words
The composition of claim 1 in wherein said cloud point modifier increases the cloud point of said surface modifier above the sterilization temperature of the nanoparticles.
Claim 13
Independent Claim
50 words
A method for of making nanoparticles having a surface modifier adsorbed on the surface and an anionic or cationic cloud point modifier associated therewith, comprised of contacting said nanoparticles with the cloud point modifier for a time and under conditions sufficient to increase the cloud point of the surface modifier.
Claim 14
Independent Claim
50 words
A method for of making nanoparticles having a surface modifier adsorbed on the surface and an anionic or cationic cloud point modifier associated therewith, comprised of contacting said nanoparticles with the cloud point modifier for a time and under conditions sufficient to increase the cloud point of the surface modifier.
Claim 15
Dependent Claim
13 words
The method of claim 12 further comprising the step of sterilizing said nanoparticle.
Claim 16
Dependent Claim
13 words
The method of claim 13 wherein said sterilizing is by steam heat autoclaving.
Claim 17
Dependent Claim
34 words
The composition of claim 1 wherein said nonionic surfactant is selected from the group consisting of polyoxyethylene alkyl ethers, polyoxyethylene castor oil derivatives, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene stearates, tyloxapol, poloxamers, and poloxamines.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1997-03-28 | 1997-09-27 | 1998-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-03-28 | 2001-09-27 | 2002-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-03-28 | 2005-09-27 | 2006-03-29 | $7700.00 | Window Closed / Lapsed |