Systems for electrical stimulation
Self-righting articles, such as self-righting capsules for administration to a subject, are generally provided. In some embodiments, the self-righting article may be configured such that the article may orient itself relative to a surface (e.g., a surface of a tissue of a subject). The self-righting articles described herein may comprise one 5 or more tissue engaging surfaces configured to engage (e.g., interface with, inject into, anchor) with a surface (e.g., a surface of a tissue of a subject). In some embodiments, the self-righting article may have a particular shape and/or distribution of density (or mass) which, for example, enables the self-righting behavior of the article. In certain embodiments, the self-righting article a tissue 10 interfacing components. In some embodiments, each tissue-interfacing component may comprise an electrically-conductive portion configured for electrical communication with tissue and an insulative portion configured to not be in electrical communication with tissue.
1. A self-righting article configured for administration to a location internal to a subject, the self-righting article comprising:
at least one tissue-interfacing component comprising an electrically-conductive portion configured for electrical communication with a tissue of the subject;
an outer shell; and
a spring at least partially encapsulated by the outer shell, the spring maintained in an at least partially compressed state by a support material under at least 5% compressive strain and in contact with the at least one tissue-interfacing component,
wherein the self-righting article is a monostatic body due to a center of mass of the self-righting article and/or the shape of the self-righting article, such that the self-righting article has a single stable resting position.
2. A self-righting article as in claim 1 , further comprising a power source in electric communication with the at least one tissue-interfacing component.
3. A self-righting article as in claim 1 , wherein the tissue-interfacing component comprises a tissue-contacting portion configured for contacting tissue, the tissue-contacting portion comprising the electrically-conductive portion configured for electrical communication with the tissue of the subject and an insulative portion configured to not be in electrical communication with tissue.
4. A self-righting article as in claim 1 , wherein the self-righting article is configured to be retained at the location internal to subject under greater than or equal to 0.6 N of force and/or a change in orientation of greater than or equal to 30 degrees.
5. A self-righting article as in claim 2 , wherein the power source is configured to generate a current.
6. A self-righting article as in claim 5 , wherein the current is greater than or equal to 2 mA and less than or equal to 5 mA.
7. A self-righting article as in claim 1 , wherein the electrically-conductive portion comprises an electrically conductive material selected from the group consisting of silver, copper, gold, stainless steel, platinum, zinc, titanium nitride, platinum iridium, and steel.
8. A self-righting article as in claim 1 , wherein the tissue-interfacing component comprises an anchoring mechanism.
9. A self-righting article as in claim 8 , wherein the anchoring mechanism comprises a hooked portion.
10. A self-righting article as in claim 1 , wherein the self-righting article is configured for oral administration to the subject.
11. A self-righting article as in claim 1 , wherein the self-righting article maintains contact with a portion of tissue at the location internal to the subject under a change of orientation of greater than or equal to 1 degree and less than or equal to 90 degrees.
12. A self-righting article as in claim 1 , wherein the self-righting article is configured to be retained at the location internal to the subject under a normal retention force of greater than or equal to 0.002 N and less than or equal to 5 N of applied force.
13. A self-righting article as in claim 1 , wherein the self-righting article is configured to be retained at the location internal to the subject under an orthogonal retention force of greater than or equal to 0.002 N and less than or equal to 5 N of applied force.
14. A self-righting article as in claim 1 , wherein the self-righting article is configured to remain anchored to the surface of the tissue located internal to the subject under less than or equal to 30 degrees change in orientation and less than or equal to 5 N of applied force.
15. A self-righting article as in claim 1 , wherein a largest dimension of at least one of the tissue-interfacing components is greater than or equal to 0.2 cm and less than or equal to 2 cm.
16. A self-righting article as in claim 8 , wherein the anchoring mechanism has an anchor length of greater than or equal to 10 microns and less than or equal to 250 microns.
17. A self-righting article as in claim 8 , wherein the anchoring mechanism has an optimal penetration depth of greater than or equal to 0.5 mm and less than or equal to 6 mm.
18. A self-righting article as in claim 8 , wherein the article is configured to be retained at a surface of tissue location internal to the subject for greater than or equal to 1 hour.
19. A self-righting article as in claim 1 , wherein the electrically conductive portion is present in the tissue contacting portion in an amount greater than or equal to 0.1% and less than or equal to 100% of the total surface area of the tissue contacting portion of the tissue-interfacing component.