High sensitivity ion selective sensors implemented through feedback circuitry

Patent metadata

Field	Value
Publication number	US-10794855-B2
Application number	US-201816117593-A
Country	US
Kind code	B2
Filing date	Aug 30, 2018
Priority date	Aug 30, 2018
Publication date	Oct 6, 2020
Grant date	Oct 6, 2020

Abstract

The following relates generally to ion sensing using organic electrochemical transistors (OECTs). In one aspect, a device comprises: an amplification portion including an OECT; a feedback portion that receives a differential voltage from the amplification portion and outputs a feedback signal; and a readout portion which receives the feedback signal and outputs an output voltage.

First claim

The invention claimed is:

1. A device for measuring ion concentration in an analyte solution, comprising:
an amplification portion comprising a first inverter and a second inverter, the first inverter comprising an ion sensing organic electrochemical transistor (OECT);
a feedback portion configured to:
receive a voltage input from the OECT; and
provide a feedback signal to the first inverter and a readout portion.

2. The device of claim 1 , wherein:
the first inverter further comprises a non-sensing OECT comprising an encapsulant; and
the second inverter comprises two non-sensing OECTs including encapsulants.

3. The device of claim 1 , wherein the feedback portion comprises a comparator, a resistor, and a capacitor.

4. The device of claim 3 , wherein the comparator is configured to:
receive the voltage input from the OECT at a positive input terminal of the comparator; and
output a feedback voltage to the capacitor and the resistor.

5. The device of claim 4 , wherein:
the capacitor is connected to a negative input terminal of the comparator; and
the resistor is connected to the first inverter and the readout portion.

6. The device of claim 5 , wherein:
the resistor has a resistance of approximately 10 MΩ; and
the capacitor has a capacitance of approximately 100 nF.

7. The device of claim 4 , wherein the negative input terminal of the comparator is further connected to the second inverter.

8. The device of claim 1 , wherein the readout portion is configured to:
receive the feedback signal at a positive input terminal of a comparator; and
output an output voltage to a negative input terminal of the comparator.

9. A device for measuring ion concentration in an analyte solution, comprising:
an amplification portion comprising a first inverter and a second inverter, the first inverter comprising an ion sensing organic electrochemical transistor (OECT);
a feedback portion configured to:
receive a differential voltage signal from the amplification portion; and
provide a feedback signal to the first inverter and a readout portion.

10. The device of claim 9 , wherein:
the first inverter further comprises a non-sensing OECT comprising an encapsulant; and
the second inverter comprises two non-sensing OECTs including encapsulants.

11. The device of claim 9 , wherein the feedback portion comprises a comparator, a resistor, and a capacitor.

12. The device of claim 11 , wherein the comparator is configured to:
receive the differential voltage from the amplification portion; and
output a feedback voltage to the capacitor and the resistor.

13. The device of claim 12 , wherein:
the capacitor is connected to a negative input terminal of the comparator; and
the resistor is connected to the first inverter and the readout portion.

14. The device of claim 13 , wherein the negative input terminal of the comparator is further connected to the second inverter.

15. The device of claim 9 , wherein:
the first inverter further comprises a non-sensing OECT comprising an encapsulant encapsulating a reference solution; and
the second inverter comprises two non-sensing OECTs including encapsulants encapsulating the reference solution.

16. A method of measuring ion concentration in an analyte solution, comprising:
with an amplification portion comprising an ion sensing organic electrochemical transistor (OECT), outputting a differential voltage to a feedback portion; and
with the feedback portion, providing a feedback signal to the amplification portion and a readout portion.

Assignees

• Palo Alto Res Ct Inc

Inventors

• Pierre Adrien
• Doris Sean Emerson
• Street Robert A

Classifications

• H03F2200/129

  there being a feedback over the complete amplifier · CPC title

• H03F2203/45116

  Feedback coupled to the input of the differential amplifier · CPC title

• G01N27/4148 Primary

  Integrated circuits therefor, e.g. fabricated by CMOS processing · CPC title

• G01N33/84

  involving inorganic compounds or pH · CPC title

• G01N33/50

  Chemical analysis of biological material, e.g. blood, urine; Testing involving biospecific ligand binding methods; Immunological testing (measuring or testing processes involving enzymes or microorganisms, compositions or test papers therefor; processes for forming such compositions, condition responsive control in microbiological or enzymological processes C12Q) · CPC title