Biomarker normalization

Abstract

A fluid sample is measured with a tear film measuring system that includes is 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 device for determining the presence of an analyte in a fluid sample comprising:
 a. a collection chamber comprising a hydrophilic polymer;   b. a fluidic channel connected to the collection chamber;   c. a sensing chamber connected to the fluidic channel,   
       wherein the sensing chamber contains a material that specifically detects the analyte and wherein the sensing chamber is operably linked to a processor that allows detection of the analyte using electrochemical sensing. 
     
     
         39 . The device of  claim 38 , wherein the processor is an electrode system, and wherein the processing of the fluid comprises applying a voltage to the electrode system to induce an electrochemical reaction between the material that specifically detects the analyte and the analyte in the fluid sample and detecting a current produced by the electrochemical reaction from the contact of the analyte with the material that specifically detects the analyte. 
     
     
         40 . The device of  claim 38 , wherein detection of the analyte comprises an enzyme modified electrochemical reaction. 
     
     
         41 . The device of  claim 38 , wherein the hydrophilic polymer comprises polyether block amides (PEBA), block-copolyether-esters (PEE), polylactic acid (PLA), polyurethanes (PU) including aliphatic and thermoplastic polyurethanes, polyglycolic acid (PGA) and other polyesters (PE), polycaprolactone (PCL), polyethersulfones (PES), polycarbonate (PC), or a combination thereof. 
     
     
         42 . The method of  claim 42 , wherein the sensing chamber comprises a receptor for the biomarker. 
     
     
         43 . The method of  claim 38 , wherein said analyte is a biomarker. 
     
     
         44 . The method of  claim 44 , wherein the biomarker is glucose. 
     
     
         45 . The method of  claim 42 , wherein said fluid sample is tear fluid. 
     
     
         46 . The method of  claim 45 , wherein volume of the tear fluid is less than 20 μl. 
     
     
         47 . The method of  claim 46 , wherein the volume of the tear fluid is between about 1 μl to about 5 μl. 
     
     
         48 . A method of determining the concentration of an analyte in a fluid sample comprising:
 a. receiving said fluid into the collection chamber of the device of  claim 38 ;   b. transferring the liquid collected in step (a) to a sensing chamber of said device to determine the presence of said analyte in said fluid   c. correlating the determined presence of the analyte in said liquid with a concentration of said analyte in said liquid.   
     
     
         49 . The method of  claim 48 , wherein receiving said fluid in the collection chamber comprises placing the tip of the collection chamber well near the eye region of a subject. 
     
     
         50 . The method of  claim 48 , wherein the sensing chamber comprises a receptor for the biomarker. 
     
     
         51 . The method of  claim 48 , wherein the analyte is a biomarker. 
     
     
         52 . The method of  claim 51 , wherein the biomarker is glucose. 
     
     
         53 . The method of  claim 48 , wherein the fluid sample is tear fluid. 
     
     
         54 . The method of  claim 53 , wherein volume of the tear fluid is less than 20 μl. 
     
     
         55 . The method of  claim 54 , wherein the volume of the tear fluid is between about 1 μl to about 5 μl.