MEASUREMENT DEVICES AND METHODS FOR MEASURING ANALYTE CONCENTRATION INCORPORATING TEMPERATURE AND PH CORRECTION

• US 20130287631A1
• Filed: 06/14/2013
• Published: 10/31/2013
• Est. Priority Date: 03/11/2010
• Status: Abandoned Application

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: GluMetrics, Inc.
• Inventors: Romey, Matthew A., Gamsey, Soya, Peyser, Thomas A.
• Application Number:
  US13/918,012
• Publication Number:
  US 20130287631A1
• Time in Patent Office: Days
• US Class Current: 422/69
• CPC Class Codes: A61B 2560/0247 for compensation or correction of the measured physiological value
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: G01N 2021/6419 Excitation at two or more wavelengths
• CPC Class Codes: G01N 2021/6484 Optical fibres
• CPC Class Codes: G01N 2021/7793 Sensor comprising plural indicators
• CPC Class Codes: G01N 21/6428 Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" in vivo A61B5/00; immunoassay G01N33/53
• CPC Class Codes: G01N 21/7703 using reagent-clad optical fibres or optical waveguides using measurement of total internal reflection or attenuated total reflection G01N21/552; optical fibres or waveguides per se G02B
• CPC Class Codes: G06F 17/00 Digital computing or data processing equipment or methods, specially adapted for specific functions information retrieval, database structures or file system structures therefor G06F16/00

Abstract

Disclosed herein are methods of estimating an analyte concentration which include generating a signal indicative of the analyte concentration, generating a signal indicative of a temperature, generating a signal indicative of a pH, and transforming the signal indicative of the analyte concentration utilizing an equation of the form of a modified Michaelis-Menten equation depending on Michaelis-Menten parameters, wherein values of the Michaelis-Menten parameters are set based upon data which includes temperature and pH calibration parameters, the signal indicative of a temperature, and the signal indicative of a pH. Also disclosed herein are measurement devices which employ the aforementioned methods.

Claims

1-27. -27. (canceled)

28. A measurement device for estimating glucose concentration comprising:

an optical sensor comprising a non-enzymatic, equilibrium fluorescence chemical indicator system disposed along a distal region of an optical fiber, the chemical indicator system comprising a fluorophore operably coupled to a glucose binding moiety, wherein the fluorophore is configured to generate a fluorescent emission signal upon excitation with light, and wherein glucose binding to the glucose binding moiety causes a change in an intensity of the fluorescent emission signal related to the glucose concentration;

a pH sensor configured to generate a signal indicative of a pH; and

a receiving and processing unit configured to transform the fluorescent emission signal intensity utilizing a first equation for correcting the glucose concentration for changes in pH, wherein the first equation is;

29. The measurement device of claim 28, further comprising:

a temperature sensor configured to generate a signal indicative of a temperature;

wherein the receiving and processing unit is further configured to transform the fluorescent emission signal intensity utilizing a second equation for correcting the glucose concentration for changes in pH and temperature, wherein the second equation is;

30. The measurement device of claim 28, wherein the optical sensor further comprises:

at least one light source configured to generate light; and

at least one detector configured to detect the fluorescent emission signal intensity and generate a signal indicative of the glucose concentration.

34. The measurement device of claim 28, wherein the indicator system further comprises an immobilizing medium configured to prevent the fluorophore and/or the binding moiety from diffusing out of the sensor.

35. The measurement device of claim 29, wherein the temperature sensor and the optical sensor are co-located along the distal region of the optical fiber.

36. The measurement device of claim 29, wherein the optical sensor further comprises:

at least one light source configured to generate light; and

at least one detector configured to detect the fluorescent emission signal intensity and generate a signal indicative of the glucose concentration.

37. The measurement device of claim 29, wherein the indicator system further comprises an immobilizing medium configured to prevent the fluorophore and/or the binding moiety from diffusing out of the sensor.

38. The measurement device claim 28, wherein the fluorophore is HPTS-triCys-MA.

39. The measurement device claim 28, wherein the glucose binding moiety comprises boronic acid.

40. The measurement device of claim 28, wherein a_pH, is defined by the equation a_pH=a_7.4*ρ

_apH(pH), wherein b_pH is defined by the equation b_pH=b_7.4*ρ

_bpH(pH), and wherein c_pH is defined by the equation c_pH=c_7.4*ρ

_cpH(pH).

41. The measurement device of claim 29, wherein a_T,pH is defined by the equation a_T,pH=a₀*τ

_aT(T)*ρ

_apH(pH), wherein b_T,pH is defined by the equation b_T,pH=b₀*τ

_bT(T)*ρ

_bpH(pH), and wherein c_T,pH is defined by the equation c_T,pH=b₀*τ

_cT(T)*ρ

_cpH(pH).

31. (canceled)

32. (canceled)

33. (canceled)