SOLUTE CONCENTRATION MEASUREMENT DEVICE AND RELATED METHODS

• US 20100071446A1
• Filed: 09/18/2009
• Published: 03/25/2010
• Est. Priority Date: 09/19/2008
• Status: Active Grant

• Current Assignee: Tandem Diabetes Care Incorporated
• Original Assignee: Tandem Diabetes Care Incorporated
• Inventors: Brown, David
• Granted Patent: US 8,650,937 B2
• Time in Patent Office: Days
• US Class Current: 73/64.470
• CPC Class Codes: G01N 1/4055 by solubility techniques
• CPC Class Codes: G01N 13/04 Investigating osmotic effects
• CPC Class Codes: G01N 2001/4061 Solvent extraction

Abstract

A solute concentration measurement device is disclosed. The device may comprise a filter membrane, an exchange chamber, a sensing chamber, a separator, and a sensor. The device may be configured to be placed in fluid communication with a sample solution containing a solute and a solvent. The filter membrane may provide selective fluid communication between the solution and the exchange chamber. The separator may separate the exchange chamber from the sensing chamber and cause a change in a condition of the sensing chamber corresponding to a change of a condition of the exchange chamber. The sensor may sense the condition pertaining to the sensing chamber and calculate the concentration of the sample solution corresponding to this change.

Claims

1. A device comprising, in combination:

a housing having disposed therein a filter membrane, an exchange chamber, and a sensing chamber having disposed therein a pressure sensor;

wherein the exchange chamber and sensing chamber are separated by a movable separator that moves in response to changes in the volume of the exchange chamber; and

wherein the device is adapted to measure the concentration of a solute in a sample solution;

wherein the solute is glucose.

2. The device of claim 1, wherein sample solution is a body fluid of an animal.

3. The device of claim 2, wherein the filter membrane provides selective fluid communication between the sample solution and the exchange chamber, but is substantially impermeable to the solute.

4. The device of claim 1, wherein movement of a fluid across the filter membrane causes a change in volume in the exchange chamber, the movement of the fluid occurring as the solute concentration in the exchange chamber equalizes with the concentration of the solute in the sample solution.

5. The device of claim 4, wherein the change in volume in the exchange chamber causes movement of the separator, which thereby effects a change in pressure in the sensing chamber.

6. The device of claim 1, wherein the pressure sensor detects the change in pressure in the sensing chamber.

7. The device of claim 1, wherein the filter membrane is an osmotic membrane.

8. The device of claim 1, further comprising a microprocessor adapted to receive inputs from the pressure sensor, whereby the microprocessor substantially calculates the concentration of the solute in the sample solution.

9. The device of claim 1, wherein the device is calibrated with a sample solution of known concentration.

10. A method comprising, in combination providing:

an exchange chamber;

a sensing chamber;

a filter membrane configured to provide selective fluid communication between the sample solution and the exchange chamber, but is substantially impermeable to a solute contained in the exchange chamber;

a movable separator configured to separate the exchange chamber from the sensing chamber; and

a sensor configured to sense a condition pertaining to the sensing chamber; and

wherein the device is adapted to be placed into fluid communication with a sample solution.

11. The method of claim 10, further comprising:

providing a calibration sample solution of known concentration for determining the amount of solute in the exchange chamber.

12. A method comprising:

placing a solute concentration measurement device comprising a housing having disposed therein at least an exchange chamber, a sensing chamber having a pressure sensor, a filter membrane substantially impermeable to the solute, and a movable separator into fluid communication with a sample solution;

measuring the pressure in the sensing chamber after allowing a solute concentration in the exchange chamber to equilibrate with a solute concentration in the sample solution; and

using the measured pressure in the sensing chamber to calculate the concentration of the solute in the sample solution.

13. The method of claim 12, further comprising:

determining the amount of a solute in the exchange chamber prior to placing the solute concentration measurement device into fluid communication with the sample solution.