Method and apparatus for non-invasive blood analyte measurement with fluid compartment equilibration

A method for determining the direction of change of a concentration of an analyte in a testing period, said method comprising the steps of:

• providing a means for analyzing a concentration of said analyte in human fluid;
• providing a means for increasing the rate of equilibration of the analyte concentration between a vascular fluid compartment and a non-vascular fluid compartment;
• activating said means for increasing the rate of equilibration of the analyte concentration and taking multiple readings of said analyte concentration;
• and
• comparing said multiple readings to determine the direction of change of said analyte in said human fluid.

A method for non-invasive spectroscopic analysis of analytes, said method comprising the steps of:

• providing a means for irradiating tissue with infrared energy;
• providing an output element, said output element operatively connected to a means for measuring a spectrum;
• providing a means for reducing analyte concentration mismatches between the vascular fluid compartment and said tissue fluid compartments;
• applying said means to said tissue and allowing sufficient time for reduction of said concentration mismatch;
• irradiating said tissue with said infrared energy so that there is differential absorption of said infrared energy in said tissue;
• and
• collecting infrared energy exiting said tissue through said output element and quantifying said infrared energy with said means for measuring a spectrum.

A method for non-invasive spectroscopic analysis of analytes in blood within a vascular system through analysis of tissue thereof, said method comprising the steps of:

• providing a means for irradiating said tissue with infrared energy;
• providing an output element, said output element operatively connected to a spectrum analyzer;
• providing an index-matching compound, said index-matching compound conforming to said surface of said tissue when applied thereto and having a refractive index closely matched to that of said tissue surface;
• disposing a quantity of said compound between said output element and said tissue surface to couple said output element to said tissue surface and said analytes in said tissue through said index-matching compound;
• providing means for equilibrating the concentration of said analyte between said vascular system and said tissue;
• activating said means for equilibrating the concentration of said analyte and allowing time for sufficient equilibration of analyte concentration between said vascular system and said tissue;
• irradiating said tissue with said infrared energy so that there is differential absorption of said infrared energy in said tissue;
• and
• collecting infrared energy exiting said tissue through said output element as coupled to said tissue surface through said index-matching compound and quantifying said infrared energy with said spectrum analyzer.

An apparatus for non-invasive measurement of an analyte in human tissue, said human tissue including multiple fluid compartments having a concentration of said analyte disposed therein, said apparatus comprising:

• a source of at least three wavelengths of light, said wavelengths being in the range of 300 to 2500 nm;
• an input sensor element for directing said light into said tissue and output sensor element for collecting at least a portion of the non-absorbed light from said tissue;
• means for increasing the rate of equilibration of the concentration of said analyte between said multiple fluid compartments until a sufficient amount of said equilibration has occurred;
• means for measuring and processing the collected portion of the non-absorbed light from said tissue after equilibration;
• and,
• means for indicating a value of said analyte concentration.

A method for non-invasive spectroscopic measurement of analytes, said method comprising the steps of:

• providing a means for irradiating tissue with infrared energy;
• providing an output element, said output element operatively connected to a spectrum analyzer;
• providing a means for increasing the rate of equilibration of analyte concentration between tissue compartments, said tissue compartments including vascular and dermal interstitial fluid compartments;
• activating said means for increasing the rate of equilibration of analyte concentration and allowing time for sufficient equilibration of analyte concentration between tissue compartments;
• irradiating said tissue adjacent said dermal interstitial fluid compartment with said infrared energy so that there is differential absorption of said infrared energy in said tissue adjacent said dermal interstitial fluid compartment;
• and
• collecting infrared energy exiting said tissue adjacent said dermal interstitial fluid compartment through said output element and quantifying said infrared energy with said spectrum analyzer.