Improvement in bioavailability of curcumin within the castor-oil based polyurethane nanocomposite through its conjugation on the surface of graphene oxide nanosheets

Abstract

Recently biocompatible polyurethane (PU) films, made from renewable bioactive compounds have been introduced as a feasible option to accelerate wound healing process. In this work, graphene oxide (GO) nanostructures were applied as a practical nanocarrier system to enhance the bioavailability of curcumin within castor-oil based PU elastomer nanocomposites. Successfully modification of GO nanosheets with curcumin (C-GO) were confirmed by FT-IR, XRD, TGA, Raman spectroscopy, and FE-SEM microscopy techniques. FE-SEM images demonstrated a good dispersion quality of C-GO nanosheets in the PU matrix, demonstrating the enhanced bioavailability of curcumin. Based on XRD diffractograms, PU/C-GO nanocomposite showed a lower crystallinity and microphase-separation degree compared to blank PU sample. This finding is probably originated from the amphiphilic properties of C-GO which provides possibility of good interactions with hard and soft domains in PU backbone. Moreover, compared to PU/GO nanocomposite, the surface modification of GO with curcumin increased the tensile strength and Young's modulus of PU/C-GO nanocomposite to 4.92 and 44.49 MPa, respectively. The in vitro MTT assay revealed a significant viability for L929 fibroblast cells in exposure with PU/C-GO film. Besides, the results of in vivo wound healing evaluation on the mouse model indicated that the PU/C-GO sample could accelerate the healing rate by promoting the proliferation and re-epithelialization of fibroblast cells in the wound site. Thus, it is suggested that the PU/C-GO nanocomposite film may has a potential and promising application as a wound dressing. © 2021 John Wiley & Sons Ltd.