Popular bioadhesives, such as fibrin, cyanoacrylate, and albumin–glutaraldehyde based materials, have been applied for clinical applications in wound healing, drug delivery, and bone and soft tissue engineering; however, their performances are limited by weak adhesion strength and rapid degradation. In this study a mussel‐inspired, nanocomposite‐based, biodegradable tissue adhesive is developed by blending poly(lactic‐co‐glycolic acid) (PLGA) or N‐hydroxysuccinimide modified PLGA nanoparticles (PLGA‐NHS) with mussel‐inspired alginate–dopamine polymer (Alg‐Dopa). Adhesive strength measurement of the nanocomposites on porcine skin–muscle constructs reveals that the incorporation of nanoparticles in Alg‐Dopa significantly enhances the tissue adhesive strength compared to the mussel‐inspired adhesive alone. The nanocomposite formed by PLGA‐NHS nanoparticles shows higher lap shear strength of 33 ± 3 kPa, compared to that of Alg‐Dopa hydrogel alone (14 ± 2 kPa). In addition, these nanocomposites are degradable and cytocompatible in vitro, and elicit in vivo minimal inflammatory responses in a rat model, suggesting clinical potential of these nanocomposites as bioadhesives.
This content will become publicly available on July 1, 2024
Adhesive tissue engineering scaffolds (ATESs) have emerged as an innovative alternative means, replacing sutures and bioglues, to secure the implants onto target tissues. Relying on their intrinsic tissue adhesion characteristics, ATES systems enable minimally invasive delivery of various scaffolds. This study investigates development of the first class of 3D bioprinted ATES constructs using functionalized hydrogel bioinks. Two ATES delivery strategies, in situ printing onto the adherend versus printing and then transferring to the target surface, are tested using two bioprinting methods, embedded versus air printing. Dopamine‐modified methacrylated hyaluronic acid (HAMA‐Dopa) and gelatin methacrylate (GelMA) are used as the main bioink components, enabling fabrication of scaffolds with enhanced adhesion and crosslinking properties. Results demonstrate that dopamine modification improved adhesive properties of the HAMA‐Dopa/GelMA constructs under various loading conditions, while maintaining their structural fidelity, stability, mechanical properties, and biocompatibility. While directly printing onto the adherend yields superior adhesive strength, embedded printing followed by transfer to the target tissue demonstrates greater potential for translational applications. Together, these results demonstrate the potential of bioprinted ATESs as off‐the‐shelf medical devices for diverse biomedical applications.
more » « less- Award ID(s):
- 2044657
- NSF-PAR ID:
- 10484505
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Biology
- Volume:
- 7
- Issue:
- 7
- ISSN:
- 2701-0198
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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