System for magnetic detection of myocardial forces

Patent metadata

Field	Value
Publication number	US-11331027-B2
Application number	US-201716082847-A
Country	US
Kind code	B2
Filing date	Mar 10, 2017
Priority date	Mar 11, 2016
Publication date	May 17, 2022
Grant date	May 17, 2022

Abstract

Devices and techniques for magnetic detection of myocardial forces are generally described. In some examples, cardiac tissue may be cultured such that the cardiac tissue adheres to a first post and a second post. In further examples, a magnetometer may detect a change in a magnetic field resulting from a deflection of the first post in a first direction from a first position to a second position. In some other examples a signal corresponding to the change in the magnetic field may be generated. In still other examples, frequencies of the signal outside of a first frequency range may be excluded to produce a filtered signal. In various examples, the first frequency range may include frequencies associated with beating of cardiac tissue. In still further examples, a force exerted by the cardiac tissue may be determined based at least in part on the filtered signal.

First claim

What is claimed is:

1. A tissue analysis device, comprising:
a base;
a first post having a proximal end coupled to the base and a distal end, wherein the first post comprises a magnetic portion, the first post being configured to have a tissue attached thereto;
a second post having a proximal end coupled to the base and a distal end, wherein the distal end of the second post is separated from the distal end of the first post by a gap, wherein the second post is configured to have the tissue attached thereto such that the tissue extends across the gap;
a magnetometer disposed proximate to the first post such that the magnetometer is configured to detect a deflection of the magnetic portion of the first post and to generate a signal in response to the deflection of the magnetic portion of the first post; and
a non-transitory machine readable storage medium storing instructions, which when executed by a processor, causes the processor to perform operations, including: determining a force exerted by the tissue based upon a known force corresponding to the signal.

2. The tissue analysis device of claim 1 , wherein the magnetometer comprises a giant magnetoresistive (GMR) sensor.

3. The tissue analysis device of claim 1 , wherein the first post and the second post are disposed in a well of a multi-well plate.

4. The tissue analysis device of claim 1 , further comprising an electromagnetic coil adjacent to the first post such that when a first current is supplied to the electromagnetic coil, the electromagnetic coil is configured to displace the distal end of the first post by attracting the magnetic portion of the first post.

5. The tissue analysis device of claim 1 , further comprising a permanent magnet adjacent to the first post configured to attract the magnetic portion of the first post with a first force.

6. The cardiac tissue analysis device of claim 1 , further comprising a filter circuit communicatively coupled to the magnetometer and configured to pass signals of a first frequency range to the processor, wherein the first frequency range includes frequencies associated with the tissue.

7. The tissue analysis device of claim 1 , wherein the first post and the second post comprise polydimethylsiloxane.

8. The tissue analysis device of claim 1 , wherein the second post comprises a rigid insert configured to prevent movement of the second post in response to contraction of the tissue coupled to the first post and the second post.

9. The tissue analysis device of claim 1 , further comprising an electromagnetic coil adjacent to the first post, wherein the electromagnetic coil is configured to:
attract the magnetic portion of the first post with a first force when a first current is supplied to the electromagnetic coil; and
attract the magnetic portion of the first post with a second force when a second current is supplied to the electromagnetic coil, wherein the second current is greater than the first current.

10. A method, comprising:
culturing a tissue adhered to a first post and a second post of a tissue analysis device, wherein the first post comprises a magnetic portion;
detecting a change in a magnetic field resulting from a deflection of the first post in a first direction from a first position to a second position;
generating a signal corresponding to the change in the magnetic field; and
determining a force exerted by the tissue based at least in part on the signal.

11. The method of claim 10 , wherein detecting the change in the magnetic field comprises detecting with a magnetometer situated proximate to the first post the change in the magnetic field.

12. The method of claim 10 , wherein the change in the magnetic field resulting from the deflection of the first post from the first position to the second position results from a contraction of the tissue.

13. The method of claim 10 , further comprising attracting the magnetic portion of the first post with an external magnet such that the first post is deflected in a second direction opposite the first direction.

14. The method of claim 10 , further comprising applying a first current to an external electromagnetic coil at a first time during a cycle of the tissue to stress the tissue by a first amount.

15. The method of claim 10 , further comprising producing a filtered signal prior to determining the force of the tissue by filtering out a second frequency range of the signal outside of a first frequency range, the first frequency range including frequencies associated with the tissue, wherein determining the force is based on the filtered signal.

16. The method of claim 15 , further comprising:
subjecting the tissue to a therapeutic agent for a period of time;
detecting, by the magnetometer situated proximate to the first post, a second change in a magnetic field resulting from a second deflection of the first post from the first position to a third position;
generating a second signal corresponding to the second change in the magnetic field;
filtering out frequencies of the second signal outside of the first frequency range to produce a second filtered signal; and
determining a second force exerted by the tissue based at least in part on the second filtered signal.

17. A method comprising:
culturing a tissue such that the tissue adheres to a first post and a second post of a tissue analysis device, wherein the first post comprises a magnetic portion;
exposing the tissue to a therapeutic agent;
generating a signal in response to a change in a magnetic field caused by movement of the magnetic portion of the first post resulting from deflection of the first post due to contraction of the tissue;
filtering out frequencies of the signal outside of a first frequency range to produce a filtered signal, wherein the first frequency range includes frequencies associated with the tissue; and
determining, based at least in part on the filtered signal, changes in force exerted by the tissue over time.

18. The method of claim 17 , further comprising:
positioning the first post and the second post in a well of a multi-well plate; and adding the therapeutic agent to the well.

19. The method of claim 17 , wherein the generating the signal in response to changes in the magnetic field comprises detecting movement of the magnetic portion of the first with a magnetometer positioned proximate to the first post.

20. The method of claim 17 , further comprising inducing movement of the first post by applying a magnetic field to the magnetic portion of the first post.

21. The method of claim 20 , wherein the applying the magnetic field to the magnetic portion of the first post comprises applying a first current to an external electromagnetic coil to induce a first strain in the tissue.

22. The method of claim 21 , wherein the applying the magnetic field to the magnetic portion of the first post comprises applying a second current to the external electromagnetic coil to induce a second strain in the tissue, wherein the second strain is different than the first strain.

Assignees

• Univ Washington

Inventors

• Sniadecki Nathan J
• Bhandari Shiv
• Bielawski Kevin S
• Leonard Andrea B
• Murry Charles E

Classifications

• C12M23/12

  Well or multiwell plates (C12M25/04 takes precedence) · CPC title

• C12M41/46

  of cellular or enzymatic activity or functionality, e.g. cell viability · CPC title

• C12M35/06

  Magnetic means (C12M35/02 takes precedence) · CPC title

• C12M21/08

  for producing artificial tissue or for ex-vivo cultivation of tissue (prostheses A61F2/00, grafts A61L27/00) · CPC title

• A61B5/7203 Primary

  for noise prevention, reduction or removal · CPC title