Method for measuring blood components and biosensor and measuring instrument for use therein

Abstract

The present invention provides a method of measuring a component in blood, by which the amounts of blood cells and an interfering substance can be measured with high accuracy and high reliability and the amount of the component can be corrected accurately based on the amounts of the blood cells and the interfering substance. In a sensor for measuring a blood component, a first working electrode 13 measures a current that flows during a redox reaction of a blood component, a second working electrode 17 measures the amount of blood cells, and a third working electrode 12 measures the amount of an interfering substance. Next, based on the measurement results, the amount of the blood component to be measured is corrected. Thus, more accurate and precise measurement of the amount of the blood component can be realized.

1 - 25 . (canceled) 
     
     
         26 . A method of determining an amount of a component in blood using a biosensor comprising a first electrode, a second electrode, and a reagent layer comprising a mediator and an oxidoreductase, said reagent layer being disposed on the second electrode;
 the method comprising:   applying a first voltage to the first electrode and a second voltage to the second electrode, wherein the second electrode has a polarity;   detecting a first current value generated by the application of the first voltage and the second voltage;   changing the polarity of the first electrode to the opposite polarity;   detecting a second current value and a third current value generated following the changing step; and   calculating an amount of the component using the first current value, the second current value and the third current value.   
     
     
         27 . The method of  claim 26 , wherein the first voltage and the second voltage are respectively applied to the first electrode and the second electrode such that the first electrode acts as a working electrode and the second electrode acts as a counter electrode. 
     
     
         28 . The method of  claim 27 , wherein the second electrode has a negative polarity. 
     
     
         29 . The method of  claim 26 , wherein changing the polarity of the first electrode comprises applying a third voltage to the first electrode such that the first electrode acts as a counter electrode. 
     
     
         30 . The method of  claim 29 , wherein the first electrode has a negative polarity. 
     
     
         31 . The method of  claim 26 , wherein the reagent layer is not disposed on the first electrode. 
     
     
         32 . The method of  claim 26 , wherein the first voltage and the second voltage are applied for a time of 0.01 to 10 seconds. 
     
     
         33 . The method of  claim 29 , wherein the third voltage is applied for a time of 0.01 to 10 seconds. 
     
     
         34 . The method of  claim 26 , wherein the amount of the component is calculated taking into account the amount of hematocrit present in the blood. 
     
     
         35 . A method of determining an amount of a component in blood using a biosensor comprising a first electrode, a second electrode, and a reagent layer comprising a mediator and an oxidoreductase, said reagent layer being disposed on the second electrode;
 the method comprising:   applying a first voltage to the first electrode, wherein the first electrode has a polarity;   detecting a first current value generated by the application of the first voltage;   changing the polarity of the first electrode to the opposite polarity;   detecting a second current value and a third current value generated following the changing step; and   calculating an amount of the component using the first current value, the second current value and the third current value.   
     
     
         36 . The method of  claim 35 , wherein the first electrode acts as a working electrode when the first voltage is applied to the first electrode. 
     
     
         37 . The method of  claim 36 , wherein the first electrode has a positive polarity. 
     
     
         38 . The method of  claim 35 , wherein changing the polarity of the first electrode comprises applying a second voltage to the first electrode such that the first electrode acts as a counter electrode. 
     
     
         39 . The method of  claim 38 , wherein the first electrode has a negative polarity. 
     
     
         40 . The method of  claim 35 , wherein the first voltage is applied for a time of 0.01 to 10 seconds. 
     
     
         41 . The method of  claim 38 , wherein the second voltage is applied for a time of 0.01 to 10 seconds.