US4705503A
Expired / Lapsed
US
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Metabolite sensor including a chemical concentration sensitive flow controller for a drug delivery system
Assignee: University of Minnesota Twin Cities
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Filing: 1986-02-03
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Granted: 1987-11-10
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Expires: 2006-02-03
Abstract
Abstract A system for the measurement of a metabolite in a physiological fluid is disclosed which comprises a catheter which includes an internal metabolite sensor downstream from a semipermeable region where dynamic equilibrium is attained between the external metabolite and a higher concentration of the same metabolite contained in an infusate which is flowed through the catheter. The changing metabolite concentration also can open and close a chemical valve to control the codelivery of a drug through the catheter.
Inventors
- 👤 Frank D. Dorman
- 👤 Bruce D. Wigness
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:45
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/145; A61B5/14532; A61M; A61M37/00; A61M5/00; A61M5/14; A61M5/168; A61M5/172; A61M5/1723; A61B5/1468; A61B5/1486; A61M25/00; A61M25/0043; A61M2025/0057
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
155 words
A method for the measurement of the concentration of a metabolite present in a physiological fluid such as blood, comprising the steps of: (a) inserting a catheter into a stream of said blood containing the metabolite; (b) flowing an aqueous infusate into said catheter at a pressure above that of the blood stream, wherein said infusate contains a concentration of said blood metabolite which is higher than the concentration of the metabolite in the blood; (c) contacting said flowing infusate with a microporous segment of the wall of said catheter for a period of time effective to bring the concentration of the metabolite within the infusate and the concentration of the metabolite in the blood into equilibrium; (d) measuring the concentration of the metabolite in the flowing infusate by means of a sensor positioned within the catheter downstream from the microporous segment; and (e) passing said flowing infusate out the catheter and into the blood.
Claim 2
Independent Claim
155 words
A method for the measurement of the concentration of a metabolite present in a physiological fluid such as blood, comprising the steps of: (a) inserting a catheter into a stream of said blood containing the metabolite; (b) flowing an aqueous infusate into said catheter at a pressure above that of the blood stream, wherein said infusate contains a concentration of said blood metabolite which is higher than the concentration of the metabolite in the blood; (c) contacting said flowing infusate with a microporous segment of the wall of said catheter for a period of time effective to bring the concentration of the metabolite within the infusate and the concentration of the metabolite in the blood into equilibrium; (d) measuring the concentration of the metabolite in the flowing infusate by means of a sensor positioned within the catheter downstream from the microporous segment; and (e) passing said flowing infusate out the catheter and into the blood.
Claim 3
Dependent Claim
17 words
The method of claim 1 wherein the catheter is implanted in a blood vessel of a human.
Claim 4
Dependent Claim
27 words
The method of claim 2 wherein the infusate is flowed through the catheter by means of a pump which is implanted in the body of a human.
Claim 5
Dependent Claim
15 words
The method of claim 3 wherein the pump provides a uniform flow rate of infusate.
Claim 6
Dependent Claim
18 words
The method of claim 1 wherein said microporous segment comprises a sheet or tube of a polymeric material.
Claim 7
Dependent Claim
22 words
The method of claim 1 wherein the sensor is an enzyme electrode sensor, a fuel cell sensor or an optical affinity sensor.
Claim 8
Dependent Claim
10 words
The method of claim 1 wherein the metabolite is glucose.
Claim 9
Dependent Claim
16 words
The method of claim 7 wherein the glucose concentration in the infusate is about 100-1000 mg/dl.
Claim 10
Dependent Claim
24 words
The method of claim 1 wherein the infusate includes an amount of an anticoagulant effective to inhibit thrombus formation on said microporous wall segment.
Claim 11
Independent Claim
129 words
A system for the measurement of a metabolite in the blood, comprising: a catheter having a fluid input port, a fluid output port, a lumen interconnecting the ports, and a microporous wall segment located between the ports which is permeable to water and to said metabolite but which is substantially impermeable to blood components of higher molecular weight; a sensor for said metabolite positioned within the lumen of said catheter at or downstream from the microporous wall segment; and means for flowing an aqueous infusate through said catheter with a pressure and metabolite concentration relatively higher than that of the blood so that the concentrations of metabolites equilibrate, whereby the amount of metabolite in the infusate measured by said sensor corresponds to the amount of metabolite in the blood.
Claim 12
Independent Claim
129 words
A system for the measurement of a metabolite in the blood, comprising: a catheter having a fluid input port, a fluid output port, a lumen interconnecting the ports, and a microporous wall segment located between the ports which is permeable to water and to said metabolite but which is substantially impermeable to blood components of higher molecular weight; a sensor for said metabolite positioned within the lumen of said catheter at or downstream from the microporous wall segment; and means for flowing an aqueous infusate through said catheter with a pressure and metabolite concentration relatively higher than that of the blood so that the concentrations of metabolites equilibrate, whereby the amount of metabolite in the infusate measured by said sensor corresponds to the amount of metabolite in the blood.
Claim 13
Dependent Claim
19 words
The system of claim 10 wherein the microporous wall segment comprises a sheet or tube of a polymeric material.
Claim 14
Dependent Claim
22 words
The system of claim 10 wherein the sensor is an enzyme electrode sensor, a fuel cell sensor or an optical affinity sensor.
Claim 15
Dependent Claim
12 words
The system of claim 10 wherein the catheter comprises a second lumen.
Claim 16
Dependent Claim
39 words
The system of claim 10 which further comprises a pump in connection with said input port of said catheter to establish a flow of a drug inan amount effective to regulate the level of said metabolite in the blood.
Claim 17
Independent Claim
229 words
A method for the controlled delivery of a drug which is effective to reduce the concentration of a metabolite present in the blood, comprising the steps of: (a) inserting a catheter into a stream of said blood containing the metabolite; (b) flowing an aqueous infusate into said catheter at a pressure above that of the blood stream, wherein said infusate contains: (i) an amount of said drug effective to reduce the concentration of said metabolite; (ii) a concentration of said metabolite which is higher than the concentration of the metabolite in blood; and (iii) a biopolymer comprising a moiety derived from said metabolite; (c) contacting said flowing infusate with a microporous segment of the wall of said catheter for a period of time effective to bring the concentration of the metabolite within the infusate and the concentration of the infusate in the blood into equilibrium, wherein said microporous segment is permeable with respect to the metabolite, but is substantially impermeable to the drug and to the biopolymer; (d) passing the infusate through a porous matrix positioned within the catheter, wherein said matrix comprises a binding substance in an amount effective to decrease the porosity of the matrix as the concentration of the metabolite in the infusate decreases by competitively complexing both the metabolite and the biopolymer; and (e) passing the flowing infusate out the catheter and into the blood.
Claim 18
Independent Claim
229 words
A method for the controlled delivery of a drug which is effective to reduce the concentration of a metabolite present in the blood, comprising the steps of: (a) inserting a catheter into a stream of said blood containing the metabolite; (b) flowing an aqueous infusate into said catheter at a pressure above that of the blood stream, wherein said infusate contains: (i) an amount of said drug effective to reduce the concentration of said metabolite; (ii) a concentration of said metabolite which is higher than the concentration of the metabolite in blood; and (iii) a biopolymer comprising a moiety derived from said metabolite; (c) contacting said flowing infusate with a microporous segment of the wall of said catheter for a period of time effective to bring the concentration of the metabolite within the infusate and the concentration of the infusate in the blood into equilibrium, wherein said microporous segment is permeable with respect to the metabolite, but is substantially impermeable to the drug and to the biopolymer; (d) passing the infusate through a porous matrix positioned within the catheter, wherein said matrix comprises a binding substance in an amount effective to decrease the porosity of the matrix as the concentration of the metabolite in the infusate decreases by competitively complexing both the metabolite and the biopolymer; and (e) passing the flowing infusate out the catheter and into the blood.
Claim 19
Dependent Claim
17 words
The method of claim 15 wherein the catheter is implanted in a blood vessel of a human.
Claim 20
Dependent Claim
15 words
The method of claim 15 wherein the catheter is inserted into an extracorporeal blood stream.
Claim 21
Dependent Claim
24 words
The method of claim 15 wherein the infusate is flowed at a constant pressure by a pump which is implanted in a human body.
Claim 22
Dependent Claim
24 words
The method of claim 15 wherein the infusate comprises an anticoagulant in an amount effective to inhibit thrombus formation on the microporous wall segment.
Claim 23
Dependent Claim
10 words
The method of claim 15 wherein the metabolite is glucose.
Claim 24
Dependent Claim
14 words
The method of claim 20 wherein the biopolymer is a polysaccharide comprising glucose sub-units.
Claim 25
Dependent Claim
10 words
The method of claim 21 wherein the polysaccharide is dextran.
Claim 26
Dependent Claim
12 words
The method of claim 15 wherein the binding substance is a lectin.
Claim 27
Dependent Claim
12 words
The method of claim 23 wherein the binding substance is conconavalin A.
Claim 28
Dependent Claim
10 words
The method of claim 15 wherein the drug is insulin.
Claim 29
Dependent Claim
14 words
The method of claim 20 wherein the infusate comprises about 100-1000 mg/dl of glucose.
Claim 30
Dependent Claim
14 words
The method of claim 25 wherein the infusate comprises about 2-1000 units/ml of insulin.
Claim 31
Dependent Claim
13 words
The method of claim 22 wherein the infusate comprises about 0.1-0.5 μM dextran.
Claim 32
Dependent Claim
16 words
The method of claim 15 wherein the pH of the infusate is buffered to about 6-8.
Claim 33
Independent Claim
130 words
A system for the controlled delivery of a drug which is effective to reduce the concentration of a metabolite present in the blood, comprising: a catheter having a fluid input port, a fluid output port, a microporous polymeric wall segment downstream from the input port which is permeable to water and to the metabolite but which is substantially impermeable to blood components of higher molecular weight, and a flow controller comprising a porous matrix positioned within catheter at or downstream from said microporous wall segment; wherein said matrix comprises a binding substance in an amount effective to decrease the porosity of the matrix as the concentration of the metabolite within the catheter decreases by competitively complexing both the metabolite and a biopolymer which comprises a moiety derived from said metabolite.
Claim 34
Independent Claim
130 words
A system for the controlled delivery of a drug which is effective to reduce the concentration of a metabolite present in the blood, comprising: a catheter having a fluid input port, a fluid output port, a microporous polymeric wall segment downstream from the input port which is permeable to water and to the metabolite but which is substantially impermeable to blood components of higher molecular weight, and a flow controller comprising a porous matrix positioned within catheter at or downstream from said microporous wall segment; wherein said matrix comprises a binding substance in an amount effective to decrease the porosity of the matrix as the concentration of the metabolite within the catheter decreases by competitively complexing both the metabolite and a biopolymer which comprises a moiety derived from said metabolite.
Claim 35
Dependent Claim
34 words
The system of claim 30 which further comprises a constant-pressure drug infusion pump in connection with said input port of said catheter, wherein said pump comprises a recycling chemical vapor-liquid constant pressure energy source.
Claim 36
Dependent Claim
10 words
The system of claim 30 wherein the metabolite is glucose.
Claim 37
Dependent Claim
12 words
The system of claim 30 wherein the binding substance comprises conconavalin A.
Claim 38
Dependent Claim
10 words
The system of claim 30 wherein the biopolymer comprises dextran.
Claim 39
Dependent Claim
12 words
The system of claim 30 wherein the porous matrix comprises polytetrafluoroethylene fibers.
Claim 40
Dependent Claim
17 words
The system of claim 30 wherein the matrix pores have an effective diameter of about 0.01-1 microns.
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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) | 1990-11-09 | 1991-05-11 | 1991-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-09 | 1995-05-11 | 1995-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-09 | 1999-05-11 | 1999-11-10 | $7700.00 | Window Closed / Lapsed |