Henry M. Rowan College of Engineering
Tissue engineering; Polymers in medicine
Tissue engineering is a multidisciplinary field that aims to repair or regenerate lost or damaged tissues and organs in the body. For the repair of certain load-bearing parts of the body, success of a tissue regeneration strategy can be dependent on scaffold adhesion or integration with the surrounding host tissue to prevent dislocation. One such area is the regeneration of the intervertebral disc (IVD). The objective of this work is to generate a bioadhesive polymer that, in addition to bonding with tissue, can support encapsulated cell survival post-adhesion. Thermosensitive poly(N-isopropylacrylamide) (PNIPAAm) was grafted with chondroitin sulfate (CS) (PNIPAAm-g-CS) and blended with aldehyde-modified CS to achieve covalent adhesion upon contact with tissue. Extracellular matrix (ECM) loaded lipid vesicles (liposomes) were incorporated into the copolymer for enhanced cellular biocompatibility. The bioadhesive strength was evaluated in contact with porcine ear cartilage. Additionally, the cytotoxicity of the samples was investigated using a PicoGreen quantitative assay. Incorporating CS aldehyde into the polymer increased the adhesive strength compared to PNIPAAm-g-CS polymer alone (p<0.05), while incorporation of ECM loaded liposomes significantly decreased adhesive strength (p<0.05). As lipid concentration increased there were decreasing trends in adhesive strength. Preliminary biocompatibility studies indicate that incorporation of ECM loaded liposomes reduced cytotoxicity over the copolymer blended with CS aldehyde and no liposomes. Future work will investigate other means of ECM encapsulation to optimize both adhesive strength and biocompatibility.
Wiltsey, Craig, "Self-assembling biomimetic hydrogels with bioadhesive properties for tissue engineering applications" (2013). Theses and Dissertations. 505.