Characterization of maghemite (γ-Fe2O3)-loaded poly-l-lactic acid/thermoplastic polyurethane electrospun mats for soft tissue engineering

Abstract

This study proposed a new mixture of three different biocompatible and biodegradable materials for soft tissue which needs elasticity and stretchability as well as stiffness. Five different ratios of poly-l-lactic acid (PLLA)/thermoplastic polyurethane (TPU) blend containing 1 % (w/v) maghemite (γ-Fe2O3) nanoparticles were electrospun and characterized in terms of morphology, degradation rate, biological compatibility, and mechanical properties for tunable properties. Neat PLLA/TPU samples were used for maghemite effect verification. The existence of three components in the electrospun mats was confirmed by Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy. Scanning electron microscopy images illustrated well-fabricated nanofibers with smaller diameter distribution for PLLA. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay using human skin fibroblast cell indicates desired proliferation and migrant over the samples. Blood biocompatibility results in terms of clotting time, fibrin formation, and hemolysis were almost in the normal range. Samples’ degradation rate was investigated over 24 weeks where the PLLA shows 47.15 % mass change, while 6.7 % of TPU mass changed. High tensile strength and an extremely low elongation at break were determined from the stress–strain curve for PLLA, while TPU exhibits high elasticity. The 50:50 % ratio of 1 % (w/v) maghemite-loaded PLLA/TPU scaffold presents an overall satisfaction.