Brachytherapy device
The disclosure relates to an improved brachytherapy device, methods of preparation, and uses thereof. More particularly, a flexible bioresorbable brachytherapy device is provided for application on a wound site in a subject. The device includes a sealed radioactive source having opposite first and second sides, wherein the sealed radioactive source includes a radioactive component comprising a plurality of radio-isotope particles dispersed within a carrier. A barrier surrounds the radioactive component providing the sealed radioactive source, wherein the barrier functions as a barrier, when implanted at the wound site, providing the sealed radioactive source for at least six half-lives of the plurality of radio-isotope particles. A bioresorbable shield located on the first side of the sealed radioactive source is configured to shield radioactivity when implanted at the wound site for at least six half-lives of the plurality of radio-isotope particles.
1 . A flexible bioresorbable brachytherapy device for application on a wound site in a subject, the device comprising:
a sealed radioactive source having opposite first and second sides, wherein the sealed radioactive source comprises:
a radioactive component comprising a plurality of radio-isotope particles dispersed within a carrier,
a barrier surrounding the radioactive component providing the sealed radioactive source,
wherein the barrier functions as a barrier, when implanted at the wound site, providing the sealed radioactive source for at least six half-lives of the plurality of radio-isotope particles,
wherein the plurality of radio-isotope particles are physically maintained in place within the sealed source such that relative movement of the plurality of radio-isotope particles is minimized for at least six half lives of the plurality of radio-isotope particles,
a bioresorbable shield in the form of a dehydrated hydrogel layer, wherein the bioresorbable shield is located on the first side of the sealed radioactive source, the bioresorbable shield configured to shield radioactivity when implanted at the wound site for at least six half-lives of the plurality of radio-isotope particles.
2 . A device according to claim 1 , wherein the device comprises an adhesive layer located on the second side of the sealed radioactive source.
3 . A device according to claim 1 , wherein the carrier comprises a biocompatible, biodegradable insoluble hydrophilic polymer.
4 . A device according to claim 3 , wherein the carrier comprises a dried film of insoluble PVOH, wherein the PVOH is insoluble under physiological conditions.
5 . A device according to claim 1 , wherein the barrier inhibits leaching of the plurality of radio-isotope particles between the sealed source and the surrounding environment by at least about 99%.
6 . A device according to claim 1 , wherein the barrier comprises a biocompatible, biodegradable hydrophobic polymer.
7 . A device according to claim 6 , wherein the barrier comprises 80-99.9% w/v PCL.
8 . A device according to claim 1 , wherein the sealed radioactive source is in the form of a unified structure.
9 . A device according to claim 1 , wherein the second side of the radioactive source is functionalized to provide a hydrophilic surface.
10 . A device according to claim 1 , wherein the bioresorbable shield is configured, when implanted at the wound site, to absorb at least about 90% radiation from the sealed radioactive source for at least six half-lives of the plurality of radio-isotope particles.
11 . A device according to claim 1 , wherein the hydrogel layer comprises PVOH, CMC, and citric acid.
12 . A device according to claim 1 , wherein the device comprises a fenestrated hydrophobic polymer layer arranged above an upper surface of the hydrogel layer.
13 . A method of preparing the flexible bioresorbable brachytherapy device according to claim 1 , the method comprising:
preparing a shielding assembly comprising the bioresorbable shield;
preparing the sealed radioactive source;
applying the shielding assembly to the first side of the sealed radioactive source; and
adhering the shielding assembly to the sealed radioactive source to provide the device;
wherein the shielding assembly is formed by:
preparing a fenestrated hydrophobic polymer layer;
preparing the dehydrated hydrogel layer;
arranging the dehydrated hydrogel layer between the fenestrated hydrophobic polymer layer and a further hydrophobic polymer layer;
adhering the fenestrated hydrophobic polymer layer and the further hydrophobic polymer layer to provide the shielding assembly.
14 . A method for minimizing and/or controlling local recurrence of tumor cells at margins of a wound site in a subject, the method comprising applying the device according to claim 1 to the wound site.