Polymer membranes for continuous analyte sensors

Patent metadata

Field	Value
Publication number	US-9549699-B2
Application number	US-201414517718-A
Country	US
Kind code	B2
Filing date	Oct 17, 2014
Priority date	Mar 28, 2008
Publication date	Jan 24, 2017
Grant date	Jan 24, 2017

Abstract

Devices and methods are described for providing continuous measurement of an analyte concentration. In some embodiments, the device has a sensing mechanism and a sensing membrane that includes at least one surface-active group-containing polymer and that is located over the sensing mechanism. The sensing membrane may have a bioprotective layer configured to substantially block the effect and/or influence of non-constant noise-causing species.

First claim

What is claimed is:

1. A device for continuous in vivo measurement of a glucose concentration, the device comprising:
an implantable sensor configured to continuously measure a signal indicative of a glucose concentration in a host;
an enzyme-containing membrane located over the sensor, wherein the enzyme-containing membrane comprises both hydrophilic and hydrophobic regions, and wherein the enzyme-containing membrane comprises:
an enzyme configured to catalyze a reaction that has glucose as a reactant; and
a polyurethane comprising a plurality of repeating hard segments and repeating soft segments, wherein a soft segment of the plurality of repeating soft segments has a molecular weight from about 200 Daltons to about 50,000 Daltons, wherein a hard segment of the plurality of repeating hard segments has a molecular weight from about 160 Daltons to about 10,000 Daltons; and

sensor electronics operably connected to the sensor, wherein the sensor electronics are configured to measure a current flow produced by the sensor to generate sensor data indicative of glucose concentration.

2. The device of claim 1 , wherein the polyurethane is a polyurethaneurea.

3. The device of claim 1 , wherein the polyurethane comprises silicone.

4. The device of claim 3 , wherein the polyurethane comprises from about 5 to about 50% silicone by weight.

5. The device of claim 1 , wherein the hydrophilic region is formed of a material selected from the group consisting of polyvinyl acetate, poly(ethylene glycol), polyacrylamide, polyethylene oxide, poly ethyl acrylate, and polyvinylpyrrolidone.

6. The device of claim 1 , wherein the membrane comprises a domain configured to reduce permeation therethrough of an interfering species.

7. The device of claim 1 , wherein the domain is located between the sensor and the first domain.

8. The device of claim 1 , wherein the domain comprises a polymer comprising ionic components.

9. The device of claim 1 , wherein the domain is configured to limit diffusion of interfering species with a molecular weight greater than a molecular weight of hydrogen peroxide.

Assignees

• Dexcom Inc

Inventors

• Boock Robert J
• Rixman Monica A
• Zhang Huashi
• Estes Michael J
• Lawrence Kristina

Classifications

• G01N27/40

  Semi-permeable membranes or partitions · CPC title

• A61B5/1473

  invasive, e.g. introduced into the body by a catheter · CPC title

• C12Q1/006

  for glucose · CPC title

• A61B5/14546

  for measuring analytes not otherwise provided for, e.g. ions, cytochromes · CPC title

• A61B5/1468

  using chemical or electrochemical methods, e.g. by polarographic means · CPC title