Patent US4474769A successfully refreshed from Google Patents.
US4474769A
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Chitosan as a contraceptive
Assignee: Ferro Pfanstiehl Laboratories Inc
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Filing: 1983-05-13
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Granted: 1984-10-02
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Expires: 2003-05-13
Abstract
Abstract A method of contraception comprising placing in the uterine cavity a contraceptively effective amount of chitosan, advantageously in a carrier, and retaining the chitosan in the uterine cavity for a prolonged period of time to kill or inactivate mammalian spermatazoa.
Inventors
- 👤 Robert L. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:13
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0012; A61K9/0034; A61K31/00; A61K31/70; A61K31/715; A61K31/716; A61K31/722; A61P; A61P5/00
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
28 words
A method of contraception which comprises placing a contraceptively effective amount of chitosan into the uterine cavity of a female animal prior to implantation of a fertilized ovum.
Claim 2
Independent Claim
28 words
A method of contraception which comprises placing a contraceptively effective amount of chitosan into the uterine cavity of a female animal prior to implantation of a fertilized ovum.
Claim 3
Dependent Claim
20 words
The method of claim 1 in which the female animal is a human and the ovum is a human ovum.
Claim 4
Dependent Claim
37 words
A method according to claim 2 wherein said chitosan is present in a carrier effective to retain it in the uterine cavity over a period of time sufficient to prevent the fertilization of the ovum by spermatozoa.
Claim 5
Dependent Claim
26 words
A method according to claim 2 wherein the chitosan is present in the uterine cavity in the form of a carrier comprising a non-toxic acidic medium.
Claim 6
Dependent Claim
13 words
A method according to claim 4 in which the carrier comprises an acid.
Claim 7
Dependent Claim
12 words
The method of claim 5 in which the carrier is ascorbic acid.
Claim 8
Dependent Claim
19 words
The method of claim 6 in which the chitosan is in the form of a solution in ascorbic acid.
Claim 9
Dependent Claim
19 words
The method of claim 5 in which the chitosan is in the form of a solution in acetic acid.
Claim 10
Independent Claim
33 words
A method of contraception in which chitosan in a motile form is placed in a contraceptually effective amount into the uterine cavity of a female animal prior to implantation of a fertilized ovum.
Claim 11
Independent Claim
33 words
A method of contraception in which chitosan in a motile form is placed in a contraceptually effective amount into the uterine cavity of a female animal prior to implantation of a fertilized ovum.
Claim 12
Dependent Claim
20 words
The method of claim 9 in which the female animal is a human and the ovum is a human ovum.
Claim 13
Dependent Claim
34 words
The method of claim 10 in which the concentration of the chitosan is present in a solution in a non-toxic acidic medium and in a concentration in the range of 10 ppm to 5%.
Claim 14
Dependent Claim
35 words
The method of claim 10 in which the chitosan is inserted in the uterine cavity in the form of an aqueous-containing acidic solution in a concentration in said solution of about 0.25% to about 1.5%.
Claim 15
Dependent Claim
34 words
The method of claim 10 in which the chitosan is inserted in the uterine cavity in the form of an aqueous-containing gel in a concentration in said gel of about 1.5 to about 10%.
Claim 16
Dependent Claim
23 words
The method of claim 10 in which the molecular weight of the chitosan lies within the range of about 30,000 to about 300,000.
Claim 17
Independent Claim
38 words
A method for killing mammalian spermatozoa which comprises contacting said spermatozoa with a spermicidally effective amount of chitosan by placing said chitosan within the uterine cavity of a female animal prior to the implantation of a fertilized ovum.
Claim 18
Independent Claim
38 words
A method for killing mammalian spermatozoa which comprises contacting said spermatozoa with a spermicidally effective amount of chitosan by placing said chitosan within the uterine cavity of a female animal prior to the implantation of a fertilized ovum.
Claim 19
Dependent Claim
18 words
The method of claim 15 in which the chitosan is applied on or in a non-toxic acidic carrier.
Claim 20
Dependent Claim
12 words
The method of claim 16 in which the spermatazoa are human spermatazoa.
Claim 21
Dependent Claim
16 words
The method of claim 17 in which the acidic carrier is an organic or inorganic acid.
Claim 22
Dependent Claim
12 words
The method of claim 18 in which the acid is ascorbic acid.
Claim 23
Dependent Claim
12 words
The method of claim 18 in which the acid is acetic acid.
Claim 24
Independent Claim
38 words
A method of inactivating mammalian spermatozoa which comprises contacting said spermatozoa with a spermatastatically effective amount of chitosan by placing said chitosan within the uterine cavity of a female animal prior to the implantation of a fertilized ovum.
Claim 25
Independent Claim
38 words
A method of inactivating mammalian spermatozoa which comprises contacting said spermatozoa with a spermatastatically effective amount of chitosan by placing said chitosan within the uterine cavity of a female animal prior to the implantation of a fertilized ovum.
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) | 1987-10-02 | 1988-04-02 | 1988-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-02 | 1992-04-02 | 1992-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-02 | 1996-04-02 | 1996-10-02 | $7700.00 | Window Closed / Lapsed |