Method of and apparatus for determining the similarity of a biological analyte from a model constructed from known biological fluids

A method of determining invasively and in vivo one or more unknown values of known characteristics, such as the concentration of an analyte, of a biological fluid in a mammal, said method comprising the steps of:

• (a) coupling invasively and in vivo a source of infrared energy with an internal portion of said mammal;
• (b) irradiating in vivo and invasively said biological fluid having said unknown values of said known characteristics with said infrared energy having at least several wavelengths so that there is differential absorption of at least some of said wavelengths by said biological fluid as a function of said wavelengths and said characteristics, said differential absorption causing intensity variations of said wavelengths incident from said biological fluid as a function of said wavelengths and said characteristics having unknown values;
• (c) measuring said intensity variations from said biological fluid;
• and
• (d) calculating said unknown values of said known characteristics in said biological fluid from said measured intensity variations from said biological fluid utilizing an algorithm and a mathematical calibration model, said algorithm including all independent sources of intensity variations v. wavelengths information obtained from irradiating a set of samples in which said values of said known characteristics are known, said algorithm also being capable of using more wavelengths than samples in said set of samples, said model being constructed from said set of samples and being a function of said known values and characteristics and said intensity variations v. wavelengths information obtained from irradiating said set of samples.

A method of determining in vitro one or more unknown values of known characteristics, such as the concentration of an analyte, of biological fluid, said method comprising the steps of:

• (a) irradiating in vitro said biological fluid having said unknown values of said known characteristics with infrared energy having at least several wavelengths so that there is differential absorption of at least some of said wavelengths by said biological fluid as a function of said wavelengths and said characteristics, said differential absorption causing intensity variations of said wavelengths incident from said biological fluid as a function of said wavelengths and said characteristics having unknown values;
• (b) measuring said intensity variations from said biological fluid;
• and
• (c) calculating said unknown values of said known characteristics in said biological fluid from said measured intensity variations from said biological fluid, utilizing an algorithm and a mathematical calibration model, said algorithm including all independent sources of intensity variations v. wavelengths information obtained from irradiating a set of samples in which said values of said known characteristics are known, said algorithm also including more wavelengths than samples in said set of samples, said model being constructed from said set of samples and being a function of said known values and characteristics, said intensity variations v. wavelengths information being obtained by irradiating said set of samples.

Apparatus for determining at least one unknown value of a known characteristic, such as the concentration of an analyte, in a biological fluid, said apparatus comprising:

• (A) a source of infrared energy having at least several wavelengths;
• (B) means for coupling said at least several wavelengths of said infrared energy to said biological fluid to enable said biological fluid to differentially absorb at least some of said wavelengths, said differential absorption causing intensity variations of said infrared energy incident from said biological fluid as a function of said at least several wavelengths of said energy and said unknown value of said known characteristic;
• (C) means for measuring said intensity variations;
• and
• (D) computer means including:
• i. a stored model constructed from a set of samples in which the values of said known characteristic are known, said model being a function of said known values from said set of samples and intensity v. wavelength information obtained from said set of samples, and
• ii. an algorithm including (a) all independent sources of said intensity variations v. said wavelengths information from both said set of samples and said biological fluid and (b) more wavelengths than samples, said algorithm utilizing said model for calculating said unknown value of said known characteristic of said biological fluid from said measured intensity variations from said biological fluid.

A method of determining in vivo at least one unknown concentration of a known characteristic in a biological fluid in a mammal, said characteristic being a trace component in said biological fluid, said concentration being less than 2.0 weight percent of said biological fluid, said method comprising:

• (a) irradiating in vivo said biological fluid having said unknown concentration of said known characteristic with infrared energy having said at least several wavelengths so that there is differential absorption of at least some of said wavelengths by said biological fluid as a function of said wavelengths and said unknown concentration, said differential absorption causing intensity variations of said wavelengths incident from said biological fluid as a function of said wavelengths and said unknown concentration;
• (b) measuring said intensity variations from said biological fluid;
• (c) calculating said unknown concentration in said biological fluid from said measured intensity variations from said biological fluid utilizing an algorithm and a mathematical calibration model, said algorithm including all independent sources of intensity variations v. wavelengths information obtained from irradiating a set of samples in which the concentrations of said known characteristic are known, said algorithm including more wavelengths than samples in said set of samples, said model being constructed from said set of samples and being a function of said known concentrations of said known characteristic and the intensity variations v. wavelengths information obtained from irradiating said set of samples;
• and
• (d) determining whether said intensity variations v. wavelengths of said biological fluids is an outlier.