Mechanical and biocompatible characterizations of a readily available multilayer vascular graft

Authors

  • Krishna Madhavan,

    1. Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, Colorado
    Search for more papers by this author
  • Winston H Elliott,

    1. Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, Colorado
    Search for more papers by this author
  • Walter Bonani,

    1. Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, Colorado
    Search for more papers by this author
  • Eric Monnet,

    1. Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
    Search for more papers by this author
  • Wei Tan

    Corresponding author
    1. Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, Colorado
    2. Department of Pediatrics, University of Colorado at Denver, Aurora, Colorado
    3. Department of Bioengineering, University of Colorado at Denver, Aurora, Colorado
    • Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, Colorado
    Search for more papers by this author

  • How to cite this article: Madhavan K, Elliott WH, Bonani W, Monnet Eric, Tan W. 2013. Mechanical and biocompatible characterizations of a readily available multilayer vascular graft. J Biomed Mater Res Part B 2013:101B:506–519.

Abstract

There is always a considerable clinical need for vascular grafts. Considering the availability, physical and mechanical properties, and regenerative potential, we have developed and characterized readily available, strong, and compliant multilayer grafts that support cell culture and ingrowth. The grafts were made from heterogeneous materials and structures, including a thin, dense, nanofibrous core composed of poly-ε-caprolactone (PCL), and a thick, porous, hydrogel sleeve composed of genipin-crosslinked collagen–chitosan (GCC). Because the difference in physicochemical properties between PCL and GCC caused layer separation, the layer adhesion was identified as a determinant to graft property and integrity under physiological conditions. Thus, strategies to modify the layer interface, including increasing porosity of the PCL surface, decreasing hydrophobicity, and increasing interlayer crosslinking, were developed. Results from microscopic images showed that increasing PCL porosity was characterized by improved layer adhesion. The resultant graft was characterized by high compliance (4.5%), and desired permeability (528 mL/cm2/min), burst strength (695 mmHg), and suture strength (2.38 N) for readily grafting. Results also showed that PCL mainly contributed to the graft mechanical properties, whereas GCC reduced the water permeability. In addition to their complementary contributions to physical and mechanical properties, the distinct graft layers also provided layer-specific structures for seeding and culture of vascular endothelial and smooth muscle cells in vitro. Acellular graft constructs were readily used to replace abdominal aorta of rabbits, resulting in rapid cell ingrowth and flow reperfusion. The multilayer constructs capable of sustaining physiological conditions and promoting cellular activities could serve as a platform for future development of regenerative vascular grafts. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.

Ancillary