Patent US5585249A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5585249A Expired / Lapsed US ⏱️ 0.0 years remaining

Polyhydroxybutyrate and polyphosphate membranes with channels

Assignee: Michigan State University
•
Filing: 1994-10-03
•
Granted: 1996-12-17
•
Expires: 2014-10-03
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Lipid bilayers which incorporate poly-3-hydroxybutyrate/polyphosphate ion channels. The ion channels are preferably purified polyhydroxybutyrate polyphosphate complexes extracted from organisms or prepared from the individual constituents which have been size selected. The bilayers are useful for testing the affect of various molecules and ions on the channel which correlates to the in vivo result. The bilayers are useful for transporting the channels into cells or other bilayers.

Inventors

  • 👤 Rosetta N. Reusch

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 16:48
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/68; G01N33/6872; A; A61; A61K; A61K9/00; A61K9/10; A61K9/127; A61K9/1271; C; C12; C12Q; C12Q1/00; C12Q1/02; C12Q1/025; G01N2500/00; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 116 words
A stable bilayer or multilayer membrane which provides a channel between a first side and a second side of the membrane which comprises: (a) a phospholipid bilayer which separates two aqueous regions wherein there is one of the regions on each of the sides of the membrane; and (b) a substantially pure mixture of (1) a polyhydroxybutyrate (PHB) and (2) a polyphosphate, the PHB and the polyphosphate each having molecular weights which allow the formation of a channel across the phospholipid wherein the membrane exhibits single channel current-voltage relationship ratios between 40 mV and 120 mV for Ca +2 , Sr +2 and Ba +2 when an identical solution is present in the two aqueous regions.
Claim 2
Dependent Claim 116 words
A stable bilayer or multilayer membrane which provides a channel between a first side and a second side of the membrane which comprises: (a) a phospholipid bilayer which separates two aqueous regions wherein there is one of the regions on each of the sides of the membrane; and (b) a substantially pure mixture of (1) a polyhydroxybutyrate (PHB) and (2) a polyphosphate, the PHB and the polyphosphate each having molecular weights which allow the formation of a channel across the phospholipid wherein the membrane exhibits single channel current-voltage relationship ratios between 40 mV and 120 mV for Ca +2 , Sr +2 and Ba +2 when an identical solution is present in the two aqueous regions.
Claim 3
Dependent Claim 18 words
The membrane of claim 1 wherein the phospholipid is selected from the group consisting of 1-palmitoyl, and 2-oleoyl-phosphatidylcholine.
Claim 4
Dependent Claim 17 words
The membrane of claim 1 wherein the PHB has a molecular weight between about 1000 and 30,000.
Claim 5
Dependent Claim 40 words
The membrane of claim 1 wherein the weight ratio of (a) to (b) is between about 1000 to 1 and 100,000 to 1 and the ratio of (1) to (2) is between about 1 to 1 and 10 to 1.
Claim 6
Dependent Claim 14 words
The membrane of claim 1 which is supported in an aperture through a plate.
Claim 7
Dependent Claim 20 words
The membrane of claim 5 wherein the aperture has a cross-sectional area of between about 50 and 300 square μm.
Claim 8
Dependent Claim 31 words
The membrane of claim 1 wherein the polyphosphate is metal polyphosphate, and the metal is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, calcium, strontium, barium and manganese.
Claim 9
Dependent Claim 31 words
The membrane of claim 1 wherein a metal ion selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, calcium, strontium, barium and manganese can be transported through the channel.
Claim 10
Dependent Claim 29 words
The membrane of claim 1 which is a bilayer membrane having a thickness between about 40 and 120 angstroms and the membrane is as a liposome or planar layer.
Claim 11
Dependent Claim 38 words
The membrane of claim 1 which is supported in an aperture through a plate having a cross-sectional area between about 50 and 1000 square μm with the bilayer membrane having a thickness between about 40 and 120 Angstroms.
Claim 12
Independent Claim 144 words
A method for forming a bilayer or multilayer membrane which has a channel between a first side and a second side of the membrane which comprises: a) mixing a phospholipid with a mixture of an inorganic polyphosphate and a polyhydroxybutyrate (PHB) in an organic solvent to provide a membrane forming solution, wherein the polyposphate and PHB each have a molecular weight which allows the formation of a channel across the phospholipid; and (b) forming a membrane which separates to aqueous regions, one on each side of the membrane between two aqueous phrases, wherein the PHB and the inorganic polyphosphate form a channel through a layer formed by the phospholipid, wherein the membrane exhibits single channel current-voltage relationship ratios between 40 mV and 120 mV for Ca +2 , Sr +2 and Ba +2 when an identical solution is present in the two aqueous regions.
Claim 13
Independent Claim 144 words
A method for forming a bilayer or multilayer membrane which has a channel between a first side and a second side of the membrane which comprises: a) mixing a phospholipid with a mixture of an inorganic polyphosphate and a polyhydroxybutyrate (PHB) in an organic solvent to provide a membrane forming solution, wherein the polyposphate and PHB each have a molecular weight which allows the formation of a channel across the phospholipid; and (b) forming a membrane which separates to aqueous regions, one on each side of the membrane between two aqueous phrases, wherein the PHB and the inorganic polyphosphate form a channel through a layer formed by the phospholipid, wherein the membrane exhibits single channel current-voltage relationship ratios between 40 mV and 120 mV for Ca +2 , Sr +2 and Ba +2 when an identical solution is present in the two aqueous regions.
Claim 14
Dependent Claim 18 words
The method of claim 11 wherein the phospholipid is selected from the group consisting of 1-palmityl, and 2-oleoyl-phosphatidylcholine.
Claim 15
Dependent Claim 17 words
The method of claim 11 wherein the PHB has the molecular weight between about 1000 and 30,000.
Claim 16
Dependent Claim 44 words
The method of claim 11 wherein the ratio of the phospholipid to the PHB and the polyphosphate is between about 1000 to 1 and 100,000 to 1 and the ratio of (1) to (2) is between about 1 to 1 and 10 to 1.
Claim 17
Dependent Claim 17 words
The method of claim 11 which is formed by being supported in an aperture through a plate.
Claim 18
Dependent Claim 20 words
The method of claim 11 wherein the aperture has a cross-sectional area of between about 50 and 1000 square μm.
Claim 19
Dependent Claim 32 words
The method of claim 11 wherein the polyphosphate is metal polyphosphate, and wherein the metal is selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, calcium, strontium, barium and manganese.
Claim 20
Dependent Claim 26 words
The method of claim 11 which is a bilayer membrane having a thickness between about 40 and 120 μm and the membrane is as a liposome.
Claim 21
Dependent Claim 39 words
The method of claim 11 which is supported in an aperture through a plate having a cross-sectional area between about 50 and 1000 square μm and with the bilayer membrane having a thickness between about 40 and 120 Angstroms.

References Cited (Backward Citations)

US4891324A Cited
US5328847A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-12-17 2000-06-17 2000-12-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-12-17 2004-06-17 2004-12-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-12-17 2008-06-17 2008-12-17 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag