Potentiostat circuit

• US 20080223719A1
• Filed: 02/08/2008
• Published: 09/18/2008
• Est. Priority Date: 02/09/2007
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Tam, Simon
• Granted Patent: US 8,133,369 B2
• Time in Patent Office: Days
• US Class Current: 204/403.01
• CPC Class Codes: G01N 27/3277 being a redox reaction, e.g. detection by cyclic voltammetry voltammetry per se G01N27/42, G01N27/48

Abstract

A potentiostat is provided for a biosensor circuit and permits sequential and simultaneous measurements to be performed at different cells across a matrix of biosensing devices. Accordingly, a potentiostat comprises a first differential amplifier for receiving a scanning voltage at a first input terminal and a voltage at the reference electrode at a second input terminal and for generating an output voltage at an output terminal to be applied to the working electrode, wherein, when in use, a feedback loop of the potentiostat circuit is closed between the reference electrode and the working electrode.

Claims

1. A potentiostat circuit, comprising:

a first differential amplifier which is configured to receive a scanning voltage at a first input terminal and a voltage of a reference electrode at a second input terminal, and generate an output voltage at an output terminal to be reflected at a working electrode, a feedback loop of the potentiostat circuit being closed between the reference electrode and the working electrode.

2. The potentiostat circuit according to claim 1, the output voltage of the first differential amplifier being applied to a first input terminal of a first operational amplifier having a negative feedback between an output terminal and a second input terminal, and the working electrode being connected to the second input terminal of the first operational amplifier and held at the voltage of the first input terminal of the first operational amplifier.

3. The potentiostat circuit according to claim 2, the first input terminal being a non-inverting input terminal and the second input terminal is an inverting input terminal.

4. The potentiostat circuit according to claim 2, further comprising:

a second differential amplifier having a first input terminal connected to the output terminal of the first operational amplifier; and

a second input terminal connected to the first input terminal of the first operational amplifier.

5. The potentiostat circuit according to claim 4,

the first input terminal of the second differential amplifier being an inverting input terminal and

the second input terminal of the second differential amplifier being a non-inverting input terminal.

6. The potentiostat circuit according to claim 1, further comprising:

a second operational amplifier having a first input terminal connected to the reference electrode; and

an output terminal connected to the second input terminal of the first differential amplifier.

7. A single-channel biosensor circuit comprising:

a counter electrode,

a reference electrode,

a working electrode, and

a potentiostat circuit according to claim 1.

8. A multi-channel biosensor circuit including a potentiostat circuit according to claim 1, further comprising:

an array of counter electrodes, reference electrodes and working electrodes, each reference electrode in the array of reference electrodes being connected to a respective first terminal of a first switch; and

each working electrode in the array of working electrodes being connected to a respective first terminal of a second switch,

the first switch and the second switch each having a second terminal being connected to the potentiostat circuit, wherein

outputs of a shift register unit are connected to a gate terminal of each respective first switch and each respective second switch and thereby adapted to select a counter electrode, reference electrode and working electrode in the array of for sequential readout by the potentiostat circuit.

9. A multi-channel biosensor circuit, comprising:

an array of biosensor circuits including the single-channel biosensor circuit according to claim 7, each biosensor circuit of the array of biosensor circuits being configured to read out simultaneously.

10. The multi-channel biosensor circuit according to claim 9, an input line being shared by each respective first differential amplifier of each respective potentiostat circuit for receiving the scanning voltage.

11. The multi-channel biosensor circuit according to claim 9, each first differential amplifier of each respective potentiostat circuit being connected to a respective input line for receiving the scanning voltage.