Engineered multicomponent electrospun nanocomposite scaffolds comprising polyurethane loaded with ghee and propolis for bone tissue repair

In Ayurveda, pure ghee is used as one of the components for the treatment of pain caused by the bone fracture. In this study, novel nanocomposites based on polyurethane (PU), ghee and propolis were developed using the electrospinning technique. Morphology analysis revealed that the novel developed PU/ghee (817 +/- 138.39 nm) and PU/ghee/propolis (576 +/- 144.96 nm) nanocomposites possessed smaller fiber diameter than the pure PU membrane (890 +/- 116.911 nm). The presence of ghee and propolis in PU was confirmed by hydrogen bond formation as revealed in Fourier infrared analysis. The contact angle was found to be increased in PU/ghee (122 degrees +/- 1 degrees) indicating the hydrophobic nature while the angle was decreased in PU/ghee/propolis (55 degrees +/- 1 degrees) suggesting the hydrophilic nature. The surface roughness of electrospun nanocomposites was found to decrease while thermal stability was observed to be enhanced for the nanocomposite as indicated in atomic force microscopy and thermogravimetric analysis. Further, the blood compatibility assessments revealed the delayed activation of blood clots in the electrospun scaffolds suggesting better blood compatibility. Moreover, the hemolytic assay suggested the developed nanocomposites (PU/ghee - 1.61% and PU/ghee/propolis - 1.52%) as non-hemolytic material and also enhanced safety to RBCs. The cytocompatibility studied revealed the better proliferation rates of human fibroblast cells in the developed nanocomposites (PU/ghee - 148.3% +/- 6.028% and PU/ghee/propolis - 156.7% +/- 5.686%) indicating its non-toxicity. So, the newly developed PU/ghee and PU/ghee/propolis nanocomposites were found to possess desirable characteristics such as better physicochemical, improved blood compatibility and non-toxic behavior which might be utilized as an appropriate candidate for bone tissue engineering.