APPARATUS AND METHOD FOR DELIVERING BENEFICIAL LIQUIDS AT STEADY RATE

• US 20100022993A1
• Filed: 08/28/2009
• Published: 01/28/2010
• Est. Priority Date: 04/10/2008
• Status: Active Grant

• Current Assignee: Microlin LLC
• Original Assignee: Microlin LLC
• Inventors: Gordon, John Howard, Joshi, Ashok V., Bhavaraju, Sai, Wold, Truman
• Granted Patent: US 8,061,280 B2
• Time in Patent Office: Days
• US Class Current: 604/892.100
• CPC Class Codes: A01M 1/2044 Holders or dispensers for liquid insecticide, e.g. using wicks
• CPC Class Codes: A61L 9/12 Apparatus, e.g. holders, therefor
• CPC Class Codes: Y10T 137/2931 Diverse fluid containing pressure systems

Abstract

An apparatus for delivering a beneficial agent is disclosed in one embodiment of the invention as including a water collection chamber. A water-transporting membrane is provided to communicate with the water collection chamber. An extraction chamber receives water through the water-transporting membrane, expanding the extraction chamber. A dispensing chamber, containing a beneficial agent, is configured to contract upon expanding the extraction chamber. This causes the dispensing chamber to expel the beneficial agent through a subterranean delivery channel, such as a rigid hollow spike. In certain embodiments, a rate adjustment mechanism may control the rate that water is received through the water-transporting membrane, thereby controlling the rate the beneficial agent is expelled. The water-transporting membrane has features that repel osmagent from passing through to the water collection chamber. The apparatus features steady rate performance without refreshing the water chamber and low temperature sensitivity.

Claims

1. An apparatus to provide controlled delivery of a beneficial agent, the apparatus comprising:

a water chamber;

a water-transporting membrane in communication with the water collection chamber;

an extraction chamber to receive water through the water-transporting membrane and into the extraction chamber, thereby expanding the extraction chamber;

an osmagent in the extraction chamber;

a dispensing chamber containing a beneficial agent and contracting in response to expanding the extraction chamber; and

a port in communication with the dispensing chamber to deliver the beneficial agent.

14. The apparatus of claim 1, wherein the extraction chamber and the dispensing chamber are separated by one of a flexible diaphragm and a piston.

15. The apparatus of claim 1, wherein the flexible diaphragm comprises or is coated with a low water permeable material.

16. The apparatus of claim 15, wherein the low water permeable material comprises at least one of a metal, metal coated polymer such as metalized PET (polyethylene terephthalate), Halar, PCTFE (polychlorotrifluoroethylene), HDPE (high density polyethylene), PP (polypropylene), PEEK (polyetheretherketone), PET, FEP (fluorinated ethylene propylene), and combinations thereof.

17. The apparatus of claim 1, wherein at least one of the extraction chamber and the dispensing chamber is at least partially contained within a pouch.

18. The apparatus of claim 17, wherein the pouch comprises or is coated with a low or negligible water permeable material.

19. The apparatus of claim 18, wherein the low or negligible water permeable material comprises at least one of a metal, metal coated polymer such as metalized PET (polyethylene terephthalate), Halar, PCTFE (polychlorotrifluoroethylene), HDPE (high density polyethylene), PP (polypropylene), PEEK (polyetheretherketone), PET, FEP (fluorinated ethylene propylene), and combinations thereof.

20. The apparatus of claim 1, wherein the beneficial agent comprises a fragrance.

21. The apparatus of claim 1, further comprising a circuit to regulate electrical current flowing through the water-transporting membrane, thereby regulating water flowing through the water-transporting membrane into the extraction chamber.

22. The apparatus of claim 1, further comprising a rate adjustment mechanism to control the rate at which water is received through the water-transporting membrane.

23. The apparatus of claim 22 wherein the rate adjustment mechanism is a blind which obscures the water chamber from the water transporting membrane with varying degree.

24. The apparatus of claim 1 wherein the water container comprises a flexible wall such that the volume changes as water transports across the membrane.

25. The apparatus of claim 1 wherein the water container comprises a vent to allow gas to enter the container as water transports across the membrane.

26. The apparatus of claim 1 wherein the water container comprises a moveable wall.

32. The apparatus of claim 1 wherein the water-transporting membrane comprises more than one membrane.

33. The apparatus of claim 32 wherein at least one membrane has functional groups of a different polarity than at least one other membrane.

34. The apparatus of claim 32 wherein at least one membrane is spatially located away from another membrane with liquid therebetween.

2. An apparatus to provide controlled delivery of a beneficial agent, the apparatus comprising:

a water chamber;

a water-transporting membrane in communication with the water collection chamber wherein the membrane is configured to repel one or more osmagent constituents;

an extraction chamber to receive water through the water-transporting membrane and into the extraction chamber, thereby expanding the extraction chamber;

an osmagent in the extraction chamber;

a dispensing chamber containing a beneficial agent and contracting in response to expanding the extraction chamber; and

a port in communication with the dispensing chamber to deliver the beneficial agent.

3. The apparatus of claim 2 wherein the membrane comprises a functional group on the surface of the membrane to repel one or more osmagent constituents.

4. The apparatus of claim 3 wherein the membrane comprises a functional group on the surface of the membrane consisting of at least one of a quaternary ammonium group, a sulfonate group, or combinations thereof to repel one or more osmagent constituents.

5. The apparatus of claim 2 wherein the membrane comprises a charged functional group within the membrane to repel one or more osmagent constituents.

6. The apparatus of claim 5 wherein the charged functional group within the membrane consists of at least one of a sulfonate or a quaternary ammonium or combinations thereof.

7. The apparatus of claim 2 wherein the membrane comprises an ion exchange membrane.

8. The apparatus of claim 7 wherein the ion exchange membrane consists of at least one of an anion exchange membrane and a cation exchange membrane.

9. The apparatus of claim 7 wherein the ion exchange membrane comprises a polymer structure.

10. The apparatus of claim 9 wherein the ion exchange membrane polymer structure comprises of at least one of fluoropolymer, styrene divinyl benzene and combinations thereof.

11. The apparatus of claim 8 wherein the ion exchange membrane comprises at least one of Nafion by Dupont;

Neosepta CMX, AMX, CIMS, CMB, AHA, ACM, ACS, AFN, AFX by ASTOM Corporation, Selemion by Asahi Glass and combinations thereof.

12. The apparatus of claim 2 wherein the osmagent comprises a salt.

13. The apparatus of claim 3 wherein the osmagent comprises at least one of ammonium, phosphate, and combinations thereof.

27. A method for delivering a beneficial agent, the method comprising:

collecting water into water chamber;

transporting the water through a water-transporting membrane into an extraction chamber containing an osmagent, thereby expanding the extraction chamber;

dispensing a beneficial agent from a dispensing chamber in response to expanding the extraction chamber; and

delivering the beneficial agent.

28. The method of claim 27, wherein expanding the extraction chamber comprises deflecting a flexible diaphragm or displaceable member.

29. The method of claim 27, wherein the flexible diaphragm comprises or is coated with a material with low or negligible water permeability.

30. The method of claim 29, wherein the material with low or negligible water permeability comprises at least one of a metal, metal coated polymer such as metalized PET (polyethylene terephthalate), Halar, PCTFE (polychlorotrifluoroethylene), HDPE (high density polyethylene), PP (polypropylene), PEEK (polyetheretherketone), PET, FEP (fluorinated ethylene propylene), and combinations thereof.

31. The method of claim 27, wherein water-transporting membrane in communication with the water collection chamber wherein the membrane has a membrane feature that repels one or more osmagent constituents.