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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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E‐Suture: Mixed‐Conducting Suture for Medical Devices
Abstract Modern implantable bioelectronics demand soft, biocompatible components that make robust, low‐impedance connections with the body and circuit elements. Concurrently, such technologies must demonstrate high efficiency, with the ability to interface between the body's ionic and external electronic charge carriers. Here, a mixed‐conducting suture, the e‐suture, is presented. Composed of silk, the conducting polymer poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), and insulating jacketing polymers,the resulting e‐suture has mixed‐conducting properties at the interface with biological tissue as well as effective insulation along its length. The e‐suture can be mechanically integrated into electronics, enabling the acquisition of biopotentials such as electrocardiograms, electromyograms, and local field potentials (LFP). Chronic, in vivo acquisition of LFP with e‐sutures remains stable for months with robust brain activity patterns. Furthermore, e‐sutures can establish electrophoretic‐based local drug delivery, potentially offering enhanced anatomical targeting and decreased side effects associated with systemic administration, while maintaining an electrically conducting interface for biopotential monitoring. E‐sutures expand on the conventional role of sutures and wires by providing a soft, biocompatible, and mechanically sound structure that additionally has multifunctional capacity for sensing, stimulation, and drug delivery.
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- Award ID(s):
- 2219891
- PAR ID:
- 10485968
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- Volume:
- 13
- Issue:
- 24
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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