Kirigami-inspired stents for sustained local delivery of therapeutics
The present disclosure provides a kirigami-inspired injectable stent system. The stent systems and methods enable radial/circumferential and longitudinal delivery of an extended release of therapeutics within tubular structures of the body, such as the GI tract and trachea. According to some aspects, a kirigami-based injectable stent system is provided that can enable drug release through deposition of therapeutic-coated needles of the stent in the tubular mucosa, such as often found in the gastrointestinal tract or trachea.
1 . A stent system for treating a submucosal tissue of a subject, the system comprising:
a tubular body extending along a central axis to form a lumen within the tubular body including two cutouts each coupled to a first end and a second end of the tubular body and configured as a first and second endcap of the tubular body,
an actuator integrated within the lumen and configured to move the tubular body between a retracted position and an elongated position, wherein the tubular body encloses the actuator via the first and second endcaps; and
a pattern of a plurality of cuts formed along the tubular body and extending through the tubular body to the lumen,
wherein the pattern of the plurality of cuts deploy into a plurality of interconnected projections that are configured to extend radially away from the tubular body relative to the central axis to engage a submucosal tissue within the gastrointestinal tract or trachea of a subject when the tubular body is moved towards the elongated position.
2 . The stent of claim 1 , wherein when the tubular body is in the retracted position, the plurality of projections form a cylindrical outer surface of the tubular body.
3 . The stent of claim 1 , wherein the projections define a needle angle between about 1 degrees and about 90 degrees relative to the central axis when the projection is in a deployed position.
4 . The stent of claim 1 , wherein the projections are triangular-shaped, with a first edge and a second edge defining a cutting edge, and a base of the triangular-shaped projections defining an uncut portion of the tubular body.
5 . The stent of claim 1 , wherein the actuator is configured to elongate the tubular body to an elongated length that is between about 1% and about 100% greater than an initial length of the tubular body in the retracted position.
6 . The stent of claim 1 , wherein the actuator is a pneumatic actuator including an actuator body having an interior cavity and an inlet port, wherein the inlet port is configured to be in fluid communication with a pressurized fluid source to provide pressurized fluid to the interior cavity.
7 . The stent of claim 6 , wherein the pneumatic actuator comprises an elastomeric material.
8 . The stent of claim 6 , wherein the actuator body includes a fiber reinforcement extending along at least a portion of the length of the actuator body.
9 . The stent of claim 8 , wherein the fiber reinforcement includes strands of fibers arranged in a helical pattern.
10 . A method of inserting a stent into a gastrointestinal tract or trachea a subject, the method comprising:
positioning a stent to a target tissue site within a gastrointestinal tract or trachea, the stent having a tubular body extending along a central axis to form a lumen within the tubular body including two cutouts each coupled to a first end and a second end of the tubular body and configured as a first and second endcap of the tubular body,
pressurizing an actuator integrated within the lumen and to move the tubular body from a retracted position to an elongated position, wherein the tubular body encloses the actuator via the first and second endcaps,
wherein a surface of the tubular body includes a pattern of a plurality of cuts configured to deploy into a plurality of interconnected projections as the tubular body is moved into the elongated position to engage the target tissue site of the subject.
11 . The method of claim 10 , wherein the projections are coated in a therapeutic agent such that the therapeutic agent is delivered to the subject when the projections engage the target tissue site.
12 . The method of claim 11 , wherein the stent is inserted in a first, insertion direction, and upon moving the tubular body into the elongated position, moving the stent in a second direction opposite the first direction to drive the projections into the target tissue site.