Chitosan and polyethylene glycol copolymers and methods and devices for using same for sealing a vascular puncture
Inventors
Mylonakis, Andreas • Lim, Florencia
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-11751857-B2
Publication Date
2023-09-12
Expiration Date
Abstract
A sealant is provided for sealing a puncture through tissue that comprises an elongate first section including a proximal end, a distal end, and a cross-section sized for delivery into a puncture through tissue, and a second section extending from the distal end of the first section. The first section may be formed from a freeze-dried hydrogel that expands when exposed to physiological fluid within a puncture. The first section comprises chitosan and at least one additional polymer. The second section may be formed from a solid mass of non-freeze-dried, non-cross-linked hydrogel precursors. The precursors are in an unreactive state until exposed to an aqueous physiological environment, whereupon the precursors undergo in-situ crosslinking with one another to provide an adhesive layer bonded to the first section. The second section may further comprise chitosan. Apparatus and methods for delivering the sealant into a puncture through tissue are also provided.
Core Innovation
The invention provides an apparatus for sealing a puncture through tissue, where the puncture has a first French size. The apparatus includes a sheath having a lumen, with a sealant positioned in the lumen of the sheath. The sealant includes a first section having a proximal end, a distal end, and a cross-section sized for delivery into the puncture through tissue.
The first section is formed from a freeze-dried polyethylene glycol (PEG) and a chitosan hydrogel that expands when exposed to physiological fluid within the puncture and seals the puncture through the tissue. In the first section, the hydrogel is formed by reacting the PEG and chitosan, and then subsequently frozen, freeze-dried, and conditioned with one or more humidity and temperature cycles. The PEG comprises PEG-amine and PEG-ester, with the PEG-ester present in excess of PEG-amine, and the first section further specifies a molar ratio of chitosan to PEG-ester between about 0.0005 to about 0.001.
The sealant also includes a second section extending from the distal end of the first section. The second section comprises non-cross-linked PEG precursors, where at least some of the non-cross-linked PEG precursors are in an unreactive state. The apparatus further defines a second French size smaller than the first French size.
Claims Coverage
The partial content identifies two independent claims, each directed to an apparatus for sealing a puncture through tissue using a sheath-delivered, multi-section PEG/chitosan sealant. Across the independents, there are five main inventive features: freeze-dried PEG/chitosan hydrogel first section that expands in physiological fluid to seal; PEG-amine/PEG-ester chemistry with PEG-ester in excess and a specified chitosan-to-PEG-ester molar ratio; humidity and temperature cycle conditioning after freeze-drying; second section of non-cross-linked PEG precursors with at least some in an unreactive state; and sheath lumen delivery with a second French size smaller than the first French size in one independent.
Freeze-dried PEG and chitosan hydrogel first section that expands in physiological fluid to seal
A first section formed from a freeze-dried polyethylene glycol (PEG) and a chitosan hydrogel that expands when exposed to physiological fluid within the puncture and seals the puncture through the tissue.
PEG-amine/PEG-ester chemistry with PEG-ester in excess and chitosan-to-PEG-ester molar ratio
PEG comprises PEG-amine and PEG-ester, the PEG-ester present in excess of PEG-amine, and a molar ratio of chitosan to PEG-ester between about 0.0005 to about 0.001.
Humidity and temperature cycle conditioning of reacted PEG and chitosan hydrogel after freeze-drying
The hydrogel is formed by reacting the PEG and chitosan, and then subsequently frozen, freeze-dried, and conditioned with one or more humidity and temperature cycles.
Non-cross-linked PEG precursors in a second section with unreactive state
A second section extending from the distal end of the first section, where the second section comprises non-cross-linked PEG precursors, and wherein at least some of the non-cross-linked PEG precursors are in an unreactive state.
Sheath lumen delivery with second French size smaller than the first French size
A sheath having a lumen, wherein the sealant is positioned in the lumen of the sheath, and wherein the apparatus has a second French size smaller than the first French size.
The identified independent claims cover a sheath-delivered, two-section sealant where a freeze-dried PEG/chitosan hydrogel first section expands upon exposure to physiological fluid to seal the puncture, and a second section includes non-cross-linked PEG precursors having at least some in an unreactive state. The PEG/chitosan chemistry is constrained by PEG-amine/PEG-ester composition with PEG-ester in excess and a specified chitosan-to-PEG-ester molar ratio, with one independent additionally requiring conditioning of the reacted, freeze-dried hydrogel via one or more humidity and temperature cycles, and further requiring that a device second French size is smaller than the first French size.
Stated Advantages
Documented Applications
No documented applications found
Interested in licensing this patent?