Sweat simulation collection and sensing systems

Abstract

Biological chemicals, potentially found in blood are measured by collecting sweat and determining the concentration or meaning of the selected chemical in sweat. The sweat can be collected using a time based, interval collector 10 and analyzed using an external device. It can also be collected on a one time basis, using a flexible, chemical capacitor 50, or on a continuous basis using a chemical, field effect transducer 98.

What is claimed is: 
     
         1 . A method, comprising:
 collecting a volume of sweat from an area of skin of an individual;   determining a concentration of a first solute in the volume of sweat without quantifying the volume of sweat;   determining a concentration of a second solute in the volume of sweat to establish a ratio of the first solute to the second solute.   
     
     
         2 . The method of  claim 1 , wherein the first solute and the second solute are selected from the group consisting of: an electrolyte, glucose, lactate, a pro-inflammatory cytokine, an anti-inflammatory cytokine, a catecholamine, a neuropeptide, and a protein. 
     
     
         3 . The method of  claim 1 , further comprising:
 using the ratio to estimate a concentration of the first solute in a blood sample of the individual, wherein the second solute is a reference biomarker.   
     
     
         4 . A method, comprising:
 collecting a volume of sweat from an area of skin of an individual;   measuring a concentration of a first solute in the volume of sweat;   measuring a concentration of a reference solute in the volume of sweat; and   establishing a ratio of the first solute to the reference solute.   
     
     
         5 . The method of  claim 4 , further comprising:
 using the ratio to estimate a concentration of the first solute in a blood sample of the individual.   
     
     
         6 . The method of  claim 4 , further comprising:
 using the ratio to estimate a concentration of the first solute in a blood sample of the individual without quantifying the volume of sweat.   
     
     
         7 . The method of  claim 4 , further comprising:
 using the ratio to indicate a physiological meaning of the concentration of the first solute in a blood system of the individual.   
     
     
         8 . The method of  claim 4 , further comprising:
 using the ratio to indicate a response by the individual to a drug treatment.   
     
     
         9 . The method of  claim 4 , wherein the reference solute is chosen from the following: an electrolyte, sodium, potassium, a protein, lactate, a cytokine, a catecholamine, and a neuropeptide. 
     
     
         10 . The method of  claim 4 , wherein the concentration of the first solute and the concentration of the second solute are measured by one of the following: a mass spectroscopy technique, a colorimetric spectroscopy technique, an electrophoresis technique, an ion-selective electrode sensor, a chem-FET sensor, a biorecognition sensor, and an electrochemical sensor. 
     
     
         11 . The method of  claim 4 , further comprising a step prior to collecting the volume of sweat, the step comprising:
 stimulating the area of skin to cause the generation of sweat by one of the following: introducing a cholinergic agent into the skin using an iontophoresis electrode, or applying a cholinergic agent to the skin.   
     
     
         12 . A method, comprising:
 collecting a volume of sweat from an area of skin of an individual;   measuring a concentration of a first biomarker in the volume of sweat;   measuring a concentration of a second biomarker in the volume of sweat;   establishing a ratio of the first biomarker to the second biomarker; and   using the ratio to determine a response by the individual to a drug treatment.