Method for estimating distribution of sample

Abstract

The present invention relates to a method for estimating a distribution of a sample flowed from a first electrode toward a second electrode of an electrochemical test strip. A working voltage is provided between the first electrode and the second electrode for obtaining a first and a second currents, where a ratio of the first current to the second current is applied to estimate the distribution of the sample on the first and the second electrodes and an effectiveness of a measurement of a target analyte of the sample.

1 . A determining method for a sensor having at least a first electrode and a second electrode, comprising the steps of:
 (a) providing a target sample flowing from the first electrode to the second electrode;   (b) applying a first DC voltage with a voltage value across the first electrode and the second electrode for a first duration to make a potential of the first electrode higher than a potential of the second electrode and to generate a first Cottrell current;   (c) removing the first DC voltage;   (d) applying a second DC voltage with a voltage value across the first electrode and the second electrode for a second duration to make the potential of the second electrode higher than the potential of the first electrode and to generate a second Cottrell current, wherein the respective voltage values of the first and the second DC voltages are equal;   (e) removing the second DC voltage;   (f) repeating steps (b) to (e) at least twice;   (g) adding up respective values of the first Cottrell currents and respective values of the second Cottrell currents respectively; and   (h) obtaining a ratio of a sum of the respective values of the first Cottrell currents over a sum of the respective values of the second Cottrell currents to determine a distribution of the target sample on the first and the second electrodes.   
     
     
         2 . A method according to  claim 1 , wherein the first and the second DC voltages are determined via a cyclic voltammograms, and an S/N ratios of the first DC voltage and the second DC voltage are not smaller than 1. 
     
     
         3 . A method according to  claim 1 , wherein the sensor has a substrate on which the first and the second electrodes are configured. 
     
     
         4 . A method according to  claim 1 , wherein the first and the second electrodes have an enzyme and an electron transfer mediator thereon, and the enzyme makes the target sample generate a reaction being one selected from a group consisting of an oxidation, a reduction and a redox. 
     
     
         5 . A method according to  claim 1 , wherein the first and the second durations are between 3 ms to 2 s. 
     
     
         6 . A method according to  claim 1 , wherein the first and the second durations are equal. 
     
     
         7 . A method according to  claim 1 , wherein the first and the second DC voltages are removed for a first removing and a second removing durations respectively, and the first removing and the second removing durations are between 0 ms to 50 ms. 
     
     
         8 . A method according to  claim 1 , wherein the first and the second DC voltages are removed for a first removing and a second removing durations respectively, and the first removing and the second removing durations are equal. 
     
     
         9 . A method according to  claim 1 , wherein the first electrode and the second electrodes have respective electrochemical reaction areas being equal to each other. 
     
     
         10 . A method according to  claim 9 , wherein both the first and the second electrodes are fully covered thereon by the target sample when the ratio is 1. 
     
     
         11 . A method according to  claim 1 , wherein the first electrode and the second electrodes have respective electrochemical reaction areas, and the electrochemical reaction area of the first electrode is not equal to that of the second electrode. 
     
     
         12 . A method according to  claim 1 , wherein the sensor is an electrochemical sensor. 
     
     
         13 . A method according to  claim 1  being used for determining an effectiveness of a detection to the target sample. 
     
     
         14 . A method according to  claim 13 , wherein the detection is effective when the ratio is between 0.3 and 3.0. 
     
     
         15 . A method according to  claim 1 , wherein the value of the first Cottrell current and the value of the second Cottrell current are recorded during the first and the second durations respectively. 
     
     
         16 . A determining method for a distribution of a target sample, comprising the steps of:
 (a) providing a first and a second electrodes;   (b) providing the target sample flowing from the first electrode to the second electrode;   (c) applying a first DC voltage having a voltage value across the first electrode and the second electrode to make a potential of the first electrode higher than a potential of the second electrode and to generate a first sensing current;   (d) removing the first DC voltage;   (e) applying a second DC voltage having the voltage value across the first electrode and the second electrode to make the potential of the second electrode higher than the potential of the first electrode and to generate a second sensing current; and   (f) obtaining a ratio of a value of the first sensing current over a value of the second sensing current to determine the distribution of the target sample on the first and the second electrodes.   
     
     
         17 . A method according to  claim 16 , wherein the first and the second electrodes are configured on an electrochemical strip. 
     
     
         18 . A method according to  claim 16 , wherein the first and the second DC voltages are applied for a period for 3 ms to 2 s. 
     
     
         19 . A method according to  claim 16 , wherein the first and the second sensing currents are Cottrell currents. 
     
     
         20 . A determining method, comprising the steps of:
 (a) providing a first and a second electrodes;   (b) providing a target sample flowing from the first electrode to the second electrode;   (c) making a potential of the first electrode higher than a potential of the second electrode and to generate a first sensing current;   (d) making the potential of the second electrode higher than the potential of the first electrode and to generate a second sensing current; and   (e) obtaining a ratio of a value of the first sensing current over a value of the second sensing current to determine the distribution of the target sample on the first and the second electrodes.