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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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A Multifunctional Origami Patch for Minimally Invasive Tissue Sealing
Abstract For decades, bioadhesive materials have garnered great attention due to their potential to replace sutures and staples for sealing tissues during minimally invasive surgical procedures. However, the complexities of delivering bioadhesives through narrow spaces and achieving strong adhesion in fluid‐rich physiological environments continue to present substantial limitations to the surgical translation of existing sealants. In this work, a new strategy for minimally invasive tissue sealing based on a multilayer bioadhesive patch, which is designed to repel body fluids, to form fast, pressure‐triggered adhesion with wet tissues, and to resist biofouling and inflammation is introduced. The multifunctional patch is realized by a synergistic combination of three distinct functional layers: i) a microtextured bioadhesive layer, ii) a dynamic, blood‐repellent hydrophobic fluid layer, and iii) an antifouling zwitterionic nonadhesive layer. The patch is capable of forming robust adhesion to tissue surfaces in the presence of blood, and exhibits superior resistance to bacterial adhesion, fibrinogen adsorption, and in vivo fibrous capsule formation. By adopting origami‐based fabrication strategies, it is demonstrated that the patch can be readily integrated with a variety of minimally invasive end effectors to provide facile tissue sealing in ex vivo porcine models, offering new opportunities for minimally invasive tissue sealing in diverse clinical scenarios.
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- Award ID(s):
- 1935291
- PAR ID:
- 10452205
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 33
- Issue:
- 11
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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