Implantable analyte sensor

Abstract

An implantable analyte sensor including a sensing region for measuring the analyte and a non-sensing region for immobilizing the sensor body in the host. The sensor is implanted in a precisely dimensioned pocket to stabilize the analyte sensor in vivo and enable measurement of the concentration of the analyte in the host before and after formation of a foreign body capsule around the sensor. The sensor further provides a transmitter for RF transmission through the sensor body, electronic circuitry, and a power source optimized for long-term use in the miniaturized sensor body.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application is a division of U.S. application Ser. No. 10 / 838,658 filed May 3, 2004, which is incorporated by reference herein in its entirety, and is hereby made a part of this specification.FIELD OF THE INVENTION[0002]The present invention relates generally to systems and methods for making and using an implantable analyte sensor.BACKGROUND OF THE INVENTION[0003]Diabetes mellitus is a disorder in which the pancreas cannot create sufficient insulin (Type I or insulin dependent) and / or in which insulin is not effective (Type 2 or non-insulin dependent). In the diabetic state, the victim suffers from high blood sugar, which may cause an array of physiological derangements (for example, kidney failure, skin ulcers, or bleeding into the vitreous of the eye) associated with the deterioration of small blood vessels. A hypoglycemic reaction (low blood sugar) may be induced by an inadvertent overdose of insulin, or after a normal dose of ins...

AI Technical Summary

Benefits of technology

[0006]There is a need for a device a long-term, implantable analyte sensor that functions accurately and reliably, to provide improved patient convenience and care.

[0020]In a fifth embodiment, a method for implantation of an analyte sensor in a host is provided, the method including: forming a precisely dimensioned pocket in the subcutaneous space of the host, wherein the pocket is dimensioned no greater than the dimensions of the analyte sensor; inserting the analyte sensor into the precisely-dimensioned pocket so as to minimize movement of the sensor within the pocket.

[0021]In an aspect of the fifth embodiment, the step of forming a pocket includes using a tool that allows precise dimensioning of the pocket. In an aspect of the fifth embodiment, the tool includes a head dimensioned substantially similar to the dimensions of the analyte sensor and a handle for guiding the head into the pocket. In an aspect of the fifth embodiment, the tool includes a head dimensioned smaller than the dimensions of the analyte sensor and a handle for guiding the head into the pocket.

[0043]In an aspect of the eleventh embodiment, the multilayer membrane further includes an interference layer that substantially prevents passage of potentially electrochemically interfering substances.

[0050]In a thirteenth embodiment, a method for casting a membrane for use with an electrochemical glucose sensor is provided, wherein the membrane substantially prevents passage of potentially electrochemically interfering substances, the method including: forming a sufficiently diluted solvent solution including a polymer and a solvent, wherein sufficiently diluted solvent solution includes a ratio of polymer to solvent of about 1 to 10 wt. % polymer to about 90 to 99 wt. % solvent; and applying the solvent solution at a sufficiently fast casting speed that substantially avoids film thickness inhomogeneities due to evaporation during casting of the sufficiently diluted solvent solution.

Problems solved by technology

In the diabetic state, the victim suffers from high blood sugar, which may cause an array of physiological derangements (for example, kidney failure, skin ulcers, or bleeding into the vitreous of the eye) associated with the deterioration of small blood vessels.

Conventionally, a diabetic person carries a self-monitoring blood glucose (SMBG) monitor, which typically comprises uncomfortable finger pricking methods.

Unfortunately, these time intervals are so far spread apart that the diabetic will likely find out too late, sometimes incurring dangerous side effects, of a hyper- or hypo-glycemic condition.

In fact, it is not only unlikely that a diabetic will take a timely SMBG value, but the diabetic will not know if their blood glucose value is going up (higher) or down (lower) based on conventional methods, inhibiting their ability to make educated insulin therapy decisions.

Unfortunately, each of these sensors suffers from various disadvantages, such as lack of continuous care (short-term sensors), discomfort (transcutaneous and partially implantable sensors), and inconvenience (sensors with multiple components).

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