Biosensor, biosensor chip and biosensor device
A biosensor includes a working electrode 101 , a counter electrode 102 opposing the working electrode 101 , a working electrode terminal 103 and a working electrode reference terminal 10 connected to the working electrode 101 by wires, and a counter electrode terminal 104 connected to the counter electrode 102 by a wire. By employing a structure with at least three electrodes, it is possible to assay a target substance without being influenced by the line resistance on the working electrode side.
1. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a reference terminal;
the working electrode directly connected to the working electrode terminal and to the reference terminal; and
the counter electrode connected to the counter electrode terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein substantially no current flows between the working electrode and the reference terminal of the biosensor during the assay.
2. The biosensor device of claim 1 , wherein:
the measurement circuit applies a voltage to the working electrode terminal during the assay; and
a voltage at the working electrode is not equal to the voltage at the working electrode terminal.
3. The biosensor device of claim 1 , wherein:
the measurement circuit applies a voltage to the counter electrode terminal during the assay; and
a voltage at the counter electrode is not equal to the voltage at the counter electrode terminal.
4. The biosensor device of claim 1 , wherein:
the measurement circuit applies a voltage to the working electrode terminal during the assay; and
a voltage at the reference terminal is substantially equal to a voltage at the working electrode.
5. The biosensor device of claim 1 , wherein:
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a current flowing between the working electrode and the working electrode terminal is substantially equal to a current flowing between the counter electrode and the counter electrode terminal.
6. The biosensor device of claim 1 , wherein the measurement circuit senses a voltage at the working electrode by way of the reference terminal.
7. The biosensor device of claim 1 , wherein:
the connection between the working electrode and the working electrode terminal exhibits resistive properties;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay;
a current flowing between the working electrode and the working electrode terminal is substantially equal to a current flowing between the counter electrode and the counter electrode terminal; and
the magnitude of the current is not influenced by the resistive properties of the connection between the working electrode and the working electrode terminal.
8. The biosensor device of claim 1 , wherein:
the connection between the working electrode and the working electrode terminal exhibits resistive properties;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a voltage difference between the working electrode and the working electrode terminal is a function of the resistive properties of the connection between the working electrode and the working electrode terminal.
9. The biosensor device of claim 1 , wherein:
the connection between the counter electrode and the counter electrode terminal exhibits resistive properties;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a voltage difference between the counter electrode and the counter electrode terminal is a function of the resistive properties of the connection between the counter electrode and the counter electrode terminal.
10. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a reference terminal;
the working electrode connected to the working electrode terminal; and
the counter electrode directly connected to the counter electrode terminal and to the reference terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein substantially no current flows between the counter electrode and the reference terminal during the assay.
11. The biosensor device of claim 10 , wherein:
the measurement circuit applies a voltage to the counter electrode terminal during the assay; and
a voltage at the reference terminal is substantially equal to a voltage at the counter electrode.
12. The biosensor device of claim 10 , wherein the measurement circuit senses a voltage at the counter electrode by way of the reference terminal.
13. The biosensor device of claim 10 , wherein:
the connection between the counter electrode and the counter electrode terminal exhibits resistive properties;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay;
a current flowing between the working electrode and the working electrode terminal is substantially equal to a current flowing between the counter electrode and the counter electrode terminal; and
the magnitude of the current is not influenced by the resistive properties of the connection between the counter electrode and the counter electrode terminal.
14. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a reference terminal;
a first line connecting the working electrode to the working electrode terminal;
a second line connecting the working electrode to the reference terminal; and
a third line connecting the counter electrode to the counter electrode terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein substantially no current flows through the second line during the assay.
15. The biosensor device of claim 14 , wherein:
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a current flowing through the first line is substantially equal to a current flowing through the third line.
16. The biosensor device of claim 14 , wherein:
the first line has a line resistance;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay;
a current flowing through the first line is substantially equal to a current flowing through the third line; and
the magnitude of the current is not substantially influenced by the line resistance of the first line.
17. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a reference terminal;
a first line connecting the working electrode to the working electrode terminal;
a second line connecting the counter electrode to the reference terminal; and
a third line connecting the counter electrode to the counter electrode terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein substantially no current flows through the second line during the assay.
18. The biosensor device of claim 17 , wherein:
the third line has a line resistance;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay;
a current flowing through the first line is substantially equal to a current flowing through the third line; and
the magnitude of the current is not substantially influenced by the line resistance of the third line.
19. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a first reference terminal;
a second reference terminal;
the working electrode directly connected to the working electrode terminal and to the first reference terminal; and
the counter electrode directly connected to the counter electrode terminal and to the second reference terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein substantially no current flows between the working electrode and the first reference terminal during the assay, and substantially no current flows between the counter electrode and the second reference terminal during the assay.
20. The biosensor device of claim 19 , wherein:
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a voltage at the first reference terminal is substantially equal to a voltage at the working electrode during an assay; and
a voltage at the second reference terminal is substantially equal to a voltage at the counter electrode during an assay.
21. The biosensor device of claim 19 , wherein the measurement circuit senses a voltage at the working electrode by way of the first reference terminal, and senses a voltage at the counter electrode by way of the second reference terminal.
22. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a first reference terminal;
a second reference terminal;
a first line connecting the working electrode to the working electrode terminal;
a second line connecting the working electrode to the first reference terminal;
a third line connecting the counter electrode to the counter electrode terminal; and
a fourth line connecting the counter electrode and to the second reference terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein substantially no current flows through the second line during the assay, and substantially no current flows through the fourth line during the assay.
23. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a reference terminal;
the working electrode directly connected to the working electrode terminal and to the reference terminal; and
the counter electrode connected to the counter electrode terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein the measurement circuit senses a voltage at the working electrode during the assay by way of the reference terminal.
24. The biosensor device of claim 23 , wherein:
the measurement circuit applies a voltage to the working electrode terminal during the assay; and
the voltage at the working electrode is not equal to the voltage at the working electrode terminal.
25. The biosensor device of claim 23 , wherein:
the measurement circuit applies a voltage to the counter electrode terminal during the assay; and
a voltage at the counter electrode is not equal to the voltage at the counter electrode terminal.
26. The biosensor device of claim 23 , wherein:
the measurement circuit applies a voltage to the working electrode terminal during the assay; and
a voltage at the reference terminal is substantially equal to the voltage at the working electrode.
27. The biosensor device of claim 23 , wherein:
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a current flowing between the working electrode and the working electrode terminal is substantially equal to a current flowing between the counter electrode and the counter electrode terminal.
28. The biosensor device of claim 23 , wherein:
the connection between the working electrode and the working electrode terminal exhibits resistive properties;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay;
a current flowing between the working electrode and the working electrode terminal is substantially equal to a current flowing between the counter electrode and the counter electrode terminal; and
the magnitude of the current is not influenced by the resistive properties of the connection between the working electrode and the working electrode terminal.
29. The biosensor device of claim 23 , wherein:
the connection between the working electrode and the working electrode terminal exhibits resistive properties;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a voltage difference between the working electrode and the working electrode terminal is a function of the resistive properties of the connection between the working electrode and the working electrode terminal.
30. The biosensor device of claim 23 , wherein:
the connection between the counter electrode and the counter electrode terminal exhibits resistive properties;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a voltage difference between the counter electrode and the counter electrode terminal is a function of the resistive properties of the connection between the counter electrode and the counter electrode terminal.
31. The biosensor device of claim 23 , wherein substantially no current flows between the working electrode and the reference terminal of the biosensor during the assay.
32. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a reference terminal;
the working electrode connected to the working electrode terminal; and
the counter electrode directly connected to the counter electrode terminal and to the reference terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein the measurement circuit senses a voltage at the counter electrode during the assay by way of the reference terminal.
33. The biosensor device of claim 32 , wherein:
the measurement circuit applies a voltage to the working electrode terminal during the assay; and
a voltage at the working electrode is not equal to the voltage at the working electrode terminal.
34. The biosensor device of claim 32 , wherein:
the measurement circuit applies a voltage to the counter electrode terminal during the assay; and
the voltage at the counter electrode is not equal to the voltage at the counter electrode terminal.
35. The biosensor device of claim 32 , wherein:
the measurement circuit applies a voltage to the counter electrode terminal during the assay; and
a voltage at the reference terminal is substantially equal to the voltage at the counter electrode.
36. The biosensor device of claim 32 , wherein:
the connection between the counter electrode and the counter electrode terminal exhibits resistive properties;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay;
a current flowing between the working electrode and the working electrode terminal is substantially equal to a current flowing between the counter electrode and the counter electrode terminal; and
the magnitude of the current is not influenced by the resistive properties of the connection between the counter electrode and the counter electrode terminal.
37. The biosensor device of claim 32 , wherein substantially no current flows between the counter electrode and the reference terminal during the assay.
38. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a reference terminal;
a first line connecting the working electrode to the working electrode terminal;
a second line connecting the working electrode to the reference terminal; and
a third line connecting the counter electrode to the counter electrode terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein the measurement circuit senses a voltage at the working electrode during the assay by way of the reference terminal.
39. The biosensor device of claim 38 , wherein:
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a current flowing through the first line is substantially equal to a current flowing through the third line.
40. The biosensor device of claim 38 , wherein:
the first line has a line resistance;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay;
a current flowing through the first line is substantially equal to a current flowing through the third line; and
the magnitude of the current is not substantially influenced by the line resistance of the first line.
41. The biosensor device of claim 38 , wherein substantially no current flows through the second line during the assay.
42. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a reference terminal;
a first line connecting the working electrode to the working electrode terminal;
a second line connecting the counter electrode to the reference terminal; and
a third line connecting the counter electrode to the counter electrode terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein the measurement circuit senses a voltage at the counter electrode during the assay by way of the reference terminal.
43. The biosensor device of claim 42 , wherein:
the third line has a line resistance;
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay;
a current flowing through the first line is substantially equal to a current flowing through the third line; and
the magnitude of the current is not substantially influenced by the line resistance of the third line.
44. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a first reference terminal;
a second reference terminal;
the working electrode directly connected to the working electrode terminal and to the first reference terminal; and
the counter electrode directly connected to the counter electrode terminal and to the second reference terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein the measurement circuit senses a voltage at the working electrode during the assay by way of the first reference terminal, and senses a voltage at the counter electrode during the assay by way of the second reference terminal.
45. The biosensor device of claim 44 , wherein:
the measurement circuit applies a voltage to the working electrode terminal and a voltage to the counter electrode terminal during the assay; and
a voltage at the first reference terminal is substantially equal to the voltage at the working electrode during an assay; and
a voltage at the second reference terminal is substantially equal to the voltage at the counter electrode during an assay.
46. The biosensor device of claim 44 , wherein substantially no current flows between the working electrode and the first reference terminal during the assay; and substantially no current flows between the counter electrode and the second reference terminal during the assay.
47. A biosensor device, comprising:
a biosensor, comprising:
a working electrode;
a counter electrode;
a working electrode terminal;
a counter electrode terminal;
a first reference terminal;
a second reference terminal;
a first line connecting the working electrode to the working electrode terminal;
a second line connecting the working electrode to the first reference terminal;
a third line connecting the counter electrode to the counter electrode terminal; and
a fourth line connecting the counter electrode and to the second reference terminal; and
a measurement circuit connected to the biosensor for performing an assay of a fluid to determine the concentration of a substance in the fluid;
wherein the measurement circuit senses a voltage at the working electrode during the assay by way of the first reference terminal, and senses a voltage at the counter electrode during the assay by way of the second reference terminal.
48. The biosensor device of claim 47 , wherein substantially no current flows through the second line during the assay, and substantially no current flows through the fourth line during the assay.