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Tissue failure at suture lines contributes to complications and readmissions following complex surgeries in distensible organs such as those performed in the lower urinary tract. Excess tension at points of tissue approximation can contribute to abnormal wound healing, urine leaks, infections, and fistula development. A flexible biodegradable adhesive patch that adheres to dynamic tissue and prevents non-targeted adhesion to adjacent tissue is needed to provide support at suture sites throughout the wound healing process. Herein, we have developed a ready-to-use bilayer adhesive patch (BLAP) to reinforce suture lines for application to expandable and dynamic fluid-filled tissues such as the bladder. The external non-adhesive layer of BLAP comprises a bioabsorbable poly(glycerol sebacate) (PGS) elastomer, preventing undesired adhesion to the adjunct tissues. The internal tissue binding layer is composed of PGS modified with L-dopamine (L-DOPA) to allow immediate adhesion to the wet surface of the target tissue. Physical and mechanical properties of the patches were tuned by varying glycerol to sebacate ratios, L-DOPA contents, and curing time to achieve compliance that approximates that of bladder tissue. The candidate PG2S and PG2SD0.018 biomaterials of the designed BLAP demonstrated Young's moduli of 49.4 kPa and 61.5 kPa and stretchability between 174.7% and 223.7%, respectively. BLAP adhered tightly to a porcine bladder repaired cystotomy ex vivo, reinforcing the sutured line and increasing bladder burst pressure more than stand-alone surgical sutures or a commercial bioadhesive glue, Tisseel®. These features, combined with >90% cytocompatibility and biodegradability, render BLAP a promising elastic bioadhesive patch to reinforce suture lines in the bladder. Beyond the urinary tract, BLAP has the potential to be mechanically tuned for a variety of other non-planar, dynamic tissues.
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Sprayable Hydrogel Sealant for Gastrointestinal Wound Shielding
Abstract Naturally occurring internal bleeding, such as in stomach ulcers, and complications following interventions, such as polyp resection post‐colonoscopy, may result in delayed (5–7 days) post‐operative adverse events—such as bleeding, intestinal wall perforation, and leakage. Current solutions for controlling intra‐ and post‐procedural complications are limited in effectiveness. Hemostatic powders only provide a temporary solution due to their short‐term adhesion to GI mucosal tissues (less than 48 h). In this study, a sprayable adhesive hydrogel for facile application and sustained adhesion to GI lesions is developed using clinically available endoscopes. Upon spraying, the biomaterial (based on polyethyleneimine‐modified Pluronic micelles precursor and oxidized dextran) instantly gels upon contact with the tissue, forming an adhesive shield. In vitro and in vivo studies in guinea pigs, rabbits, and pig models confirm the safety and efficacy of this biomaterial in colonic and acidic stomach lesions. The authors' findings highlight that this family of hydrogels ensures prolonged tissue protection (3–7 days), facilitates wound healing, and minimizes the risk of delayed complications. Overall, this technology offers a readily adoptable approach for gastrointestinal wound management.
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- Award ID(s):
- 2335845
- PAR ID:
- 10498289
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 36
- Issue:
- 24
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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