Patent US5797898A successfully refreshed from Google Patents.
US5797898A
Expired / Lapsed
US
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Microchip drug delivery devices
Assignee: Massachusetts Institute of Technology
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Filing: 1996-07-02
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Granted: 1998-08-25
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Expires: 2016-07-02
Abstract
Abstract Microchips are provided, which control both the rate and time of release of multiple chemical substances and which allow for the release of a wide variety of molecules in either a continuous or pulsatile manner. In all of the preferred embodiments, a material that is impermeable to the drugs or other molecules to be delivered and the surrounding fluids is used as the substrate. Reservoirs are etched into the substrate using either chemical (wet) etching or ion beam (dry) etching techniques well known in the field of microfabrication. Hundreds to thousands of reservoirs can be fabricated on a single microchip using these techniques. The molecules to be delivered are inserted into the reservoirs by injection or spin coating methods in their pure form or in a release system. Exemplary release systems include polymers and polymeric matrices, non-polymeric matrices, and other excipients or diluents. The physical properties of the release system control the rate of release of the molecules. The reservoirs can contain multiple drugs or other molecules in variable dosages. The filled reservoirs can be capped with materials that either degrade or allow the molecules to diffuse passively out of the reservoir over time or materials that oxidize and dissolve upon application of an electric potential. Release from an active device can be controlled by a preprogrammed microprocessor, remote control, or by biosensors.
Inventors
- 👤 John T. Santini, Jr.
- 👤 Michael J. Cima
- 👤 Robert S. Langer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:56
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/0002; A61K9/0009; A61K9/0087; A61K9/0097; C; C25; C25F; C25F7/00; A61M; A61M2205/00; A61M2205/02; A61M2205/0244; A61M37/00
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
75 words
A microchip device for the release of molecules comprising a substrate, at least two reservoirs in the substrate containing the molecules, and each reservoir having a reservoir cap positioned on the reservoir over the molecules so that the molecules are released from the device by diffusion through or upon disintegration of the reservoir caps, and wherein release of the molecules from the reservoir is controlled by said diffusion through or disintegration of the reservoir cap.
Claim 2
Dependent Claim
75 words
A microchip device for the release of molecules comprising a substrate, at least two reservoirs in the substrate containing the molecules, and each reservoir having a reservoir cap positioned on the reservoir over the molecules so that the molecules are released from the device by diffusion through or upon disintegration of the reservoir caps, and wherein release of the molecules from the reservoir is controlled by said diffusion through or disintegration of the reservoir cap.
Claim 3
Dependent Claim
23 words
The device of claim 1 further comprising a plurality of reservoirs comprising different types of molecules, different amounts of molecules, or combinations thereof.
Claim 4
Dependent Claim
22 words
The device of claim 1 wherein release of the molecules is controlled by a release system incorporating the molecules in the reservoir.
Claim 5
Dependent Claim
33 words
The device of claim 3 wherein at least one reservoir cap is disintegratable and the release system in a reservoir is disintegratable to release the molecules after the disintegration of the reservoir cap.
Claim 6
Dependent Claim
24 words
The device of claim 3 wherein the reservoir comprises layers of different release system and reservoir cap materials such that pulsatile release is obtained.
Claim 7
Dependent Claim
43 words
The device of claim 3 wherein at least one reservoir cap is disintegratable and the release system is non-disintegratable, and diffusion of the molecules out of the release system provides a pulsed release of the molecules after the disintegration of the reservoir cap.
Claim 8
Dependent Claim
56 words
The device of claim 3 further comprising a cathode, a microprocessor, a timer, a demultiplexer, and a power source, wherein at least one reservoir cap is an anode, wherein upon application of an electric potential between the cathode and anode, at least one reservoir cap disintegrates, and exposes the underlying release system to the surrounding fluids.
Claim 9
Dependent Claim
47 words
The device of claim 7 wherein each reservoir is capped by an anodic reservoir cap, wherein the microprocessor function is directed by a source of memory preprogrammed to control the application of an electric potential between the cathode and the anode of individual reservoirs at specific times.
Claim 10
Dependent Claim
31 words
The device of claim 7 wherein the microprocessor function is directed by remote control to control the application of an electric potential between the cathode and the anode of the reservoir.
Claim 11
Dependent Claim
35 words
The device of claim 7 further comprising a biosensor, wherein the microprocessor function is directed by the biosensor to control the application of an electric potential between the cathode and the anode of the reservoir.
Claim 12
Dependent Claim
17 words
The device of claim 3 wherein the release system comprises drug molecules in an excipient or diluent.
Claim 13
Dependent Claim
35 words
The device of claim 3 wherein the release system in the reservoir is formed of the molecules to be released, wherein the dissolution rate of the molecules determines the rate of release of the molecules.
Claim 14
Dependent Claim
33 words
The device of claim 1 wherein at least one reservoir cap is disintegratable and wherein the disintergragtion rate of the cap determines the time at which the molecules are released from the reservoir.
Claim 15
Dependent Claim
21 words
The device of claim 13, further comprising a plurality of reservoirs and reservoir caps wherein the reservoir caps have different thicknesses.
Claim 16
Dependent Claim
37 words
The device of claim 1 wherein at least one reservoir cap is non-disintegratable and wherein the rate of diffusion of the molecules through the cap determines the time at which the molecules are released from the reservoirs.
Claim 17
Independent Claim
96 words
A method for the delivery of molecules comprising providing at a site where the molecules are to be delivered a microchip device for the release of molecules, wherein the microchip comprises a substrate, at least two reservoirs in the substrate containing the molecules to be delivered, and each reservoir having a reservoir cap positioned on the reservoir so that the molecules are released from the device by diffusion through or upon disintegration of the reservoir caps, and controlling the release of the molecules from the reservoir by said diffusion through or disintegration of the reservoir cap.
Claim 18
Independent Claim
96 words
A method for the delivery of molecules comprising providing at a site where the molecules are to be delivered a microchip device for the release of molecules, wherein the microchip comprises a substrate, at least two reservoirs in the substrate containing the molecules to be delivered, and each reservoir having a reservoir cap positioned on the reservoir so that the molecules are released from the device by diffusion through or upon disintegration of the reservoir caps, and controlling the release of the molecules from the reservoir by said diffusion through or disintegration of the reservoir cap.
Claim 19
Dependent Claim
19 words
The method of claim 16 wherein the molecules are drugs, comprising implanting or injecting the microchip into a patient.
Claim 20
Dependent Claim
28 words
The method of claim 17 wherein the molecules are a drug selected from the group consisting of nucleic acids, proteins, amino acids, polysaccharides, and organic or synthetic molecules.
Claim 21
Dependent Claim
16 words
The method of claim 18 wherein the drugs are in combination with a pharmaceutically acceptable carrier.
Claim 22
Dependent Claim
13 words
The method of claim 16 wherein the molecules are diagnostic or chemical reagents.
Claim 23
Dependent Claim
16 words
The method of claim 16 wherein the molecules are released in a pulsatile or continuous manner.
Claim 24
Dependent Claim
23 words
The method of claim 16 further comprising controlling the release of the molecules by a release system incorporating the molecules in the reservoir.
Claim 25
Dependent Claim
17 words
The method of claim 22 wherein the release system is formed by the molecules to be released.
Claim 26
Dependent Claim
53 words
The method of claim 22 wherein at least one reservoir cap is disintegratable and the reservoir caps are positioned on the reservoirs over the release system, wherein the disintegration rate of the cap or rate of molecule diffusion through the cap determines the time at which the molecules are released from the reservoir.
Claim 27
Dependent Claim
61 words
The method of claim 22 wherein the device further comprises a cathode, a microprocessor, a timer, a demultiplexer, and a power source, wherein at least one reservoir cap is an anode and wherein the method further comprises applying an electric potential between the cathode and anode, to oxidize the reservoir cap and expose the underlying release system to the surrounding fluids.
Claim 28
Dependent Claim
45 words
The method of claim 25 wherein the microprocessor function is directed by a source of memory preprogrammed to control the application of an electric potential between the cathode and the anode of individual reservoirs at specific times, wherein the method further comprises programming the memory.
Claim 29
Dependent Claim
34 words
The method of claim 25 wherein the method further comprises directing the microprocessor function by remote control to control the application of an electric potential between the cathode and the anode of each reservoir.
Claim 30
Dependent Claim
41 words
The method of claim 25 wherein the device further comprises a biosensor, wherein the method further comprises directing the microprocessor function by the biosensor to control the application of an electric potential between the cathode and the anode of each reservoir.
Claim 31
Dependent Claim
37 words
The method of claim 16 wherein at least one reservoir cap is non-disintegratable and wherein the rate of diffusion of the molecules through the cap determines the time at which the molecules are released from the reservoirs.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-08-24 | 2002-02-23 | 2002-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-08-24 | 2006-02-23 | 2006-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-08-24 | 2010-02-23 | 2010-08-25 | $7700.00 | Window Closed / Lapsed |