US3760804A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Improved osmotic dispenser employing magnesium sulphate and magnesium chloride
Assignee: Alza Corp
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Filing: 1971-01-13
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Granted: 1973-09-25
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Expires: 1991-01-13
Abstract
Abstract An osmotic dispenser is described which is capable of releasing to its outside environment concentrations of active agent at an osmotically controlled rate over a prolonged period of time, and the motive force of which dispenser depends on the osmotic pressure developed by either (1) an aqueous solution of magnesium sulphate, preferably a saturated aqueous solution, or (2) a saturated aqueous solution of magnesium chloride containing excess magnesium sulphate solute in solid form, against a hypotonic aqueous environment.
Inventors
- 👤 T Higuchi
- 👤 H Leeper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 17:20
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0002; A61K9/0004; A61F; A61F6/00; A61F6/06; A61F6/14
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
19 words
The osmotic dispenser as defined by claim 1, wherein the solution of magnesium sulphate is a saturated aqueous solution.
Claim 2
Dependent Claim
19 words
The osmotic dispenser as defined by claim 2, wherein the solution contains excess magnesium sulphate solute in solid form.
Claim 3
Dependent Claim
25 words
The osmotic dispenser as defined by claim 1, wherein the active agent is selected from the group consisting of a drug and a bio-affecting composition.
Claim 4
Dependent Claim
164 words
In an osmotic active agent dispenser comprised of a first compartment of relatively impervious material containing an active agent and provided with means for releasing the active agent to the exterior of the dispenser, and a second compartment of controlled permeability to water containing a solution of an osmotically effective solute which exhibits an osmotic pressure gradient against water, the said first and second compartments being so constructed that the said first diminishes in volume in response to an increase in volume of the solution in the said second via absorption of water therein, whereby as water flows into the dispenser in a tendency towards osmotic equilibrium with its environment, active agent is continuously squeezed thereout at an osmotically controlled rate over a prolonged period of time the improvement which comprises, as the solution of an osmotically effective solute in the said second compartment, a solution of magnesium chloride containing excess magnesium sulphate solute in solid form exhibiting an osmotic pressure gradient against water.
Claim 5
Dependent Claim
16 words
The osmotic dispenser as defined by claim 5, wherein the solution is a saturated aqueous solution.
Claim 6
Dependent Claim
25 words
The osmotic dispenser as defined by claim 5, wherein the active agent is selected from the group consisting of a drug and a bio-affecting composition.
References Cited (Backward Citations)
US3604417A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |