Biomarker normalization

Abstract

A fluid sample is measured with a tear film measuring system that includes a processing device that receives a sample chip comprising a sample region configured to contain an aliquot volume of sample fluid, the processing device configured to perform analyses of osmolarity and of one or more biomarkers within the sample fluid, wherein the analysis of biomarkers includes normalization of biomarker concentration values.

1 - 37 . (canceled) 
     
     
         38 . A fluid measuring system for measuring osmolarity of a sample fluid and concentration of a biomarker within the sample fluid, said system comprising:
 a) a sample chip comprising a sample fluid; an optical energy source that illuminates the sample fluid; and an optical detector that receives optical energy from the illuminated sample fluid in response to imparting energy into the sample fluid, and which processes (i) optical energy properties of the sample fluid to prepare an osmolarity output signal which corresponds to osmolarity of the sample fluid, and (ii) chemical properties of the sample fluid to prepare a biomarker output signal which corresponds to concentration of a biomarker within the sample fluid; and   b) a processing device that: receives the osmolarity output signal from the sample fluid and processes the osmolarity output signal to produce an osmolarity value for the sample fluid; and receives the biomarker output signal from the sample fluid and processes the biomarker output signal to produce a biomarker concentration value for the sample fluid.   
     
     
         39 . The fluid measuring system of  claim 38 , wherein the biomarker is IgE, IgA, IgG, IgM, glucose, insulin, lactoferrin, a cytokine, a hormone, a hormone metabolite, an infectious disease phenotype, a nucleic acid, a protein, or a lipid fraction. 
     
     
         40 . The fluid measuring system of  claim 38 , further comprising normalization of biomarker concentration values. 
     
     
         41 . The fluid measuring system of  claim 40 , wherein the normalization of biomarker concentration values corrects for patient-specific tear homeostasis. 
     
     
         42 . The fluid measuring system of  claim 40 , wherein the normalization of biomarker concentration values corrects for clinician induced tear sampling variance in connection with obtaining the sample fluid. 
     
     
         43 . The fluid measuring system of  claim 38 , wherein the analyses of osmolarity and of the biomarkers are performed simultaneously. 
     
     
         44 . The fluid measuring system of  claim 38 , wherein the analyses of osmolarity and of the biomarkers are performed serially. 
     
     
         45 . The fluid measuring system of  claim 40 , wherein the normalization of biomarker concentration values is linear. 
     
     
         46 . The fluid measuring system of  claim 40 , wherein the normalization of biomarker concentration values is ratiometric. 
     
     
         47 . The fluid measuring system of  claim 40 , wherein the normalization of biomarker concentration values is exponential. 
     
     
         48 . The fluid measuring system of  claim 40 , wherein the normalization of biomarker concentration values is based on a calibration curve. 
     
     
         49 . A system as defined in  claim 38 , wherein the optical detector includes a photodiode, wherein the optical detector includes a photodiode.