Porous gelatin-based phosphorylated scaffold: Microstructure, cell response and osteogenic differentiation of human adipose-derived mesenchymal stem cells

Abstract

To repair the highly organized composite bone tissue, the design and development of biomimetic three-dimensional scaffolds is an active strategy. Here, we describe the fabrication route of a bioengineered gelatin-based scaffold for potential application in bone tissue engineering. First, phosphorus-containing polyurethane (PU–P) polymer was synthesized by polymerization starting from phosphorous polyol and methylene diisocyanate (DMI). Second, a gelatin/phosphorus-containing polyurethane (Gelatin/PU-P) scaffold was prepared by solution mixing, ultrasonication, and freeze-drying of gelatin and PU-P polymer. Next, prepared scaffold samples were characterized by FT-IR, SEM microscopy, porosity measurement, swelling, degradability, and mechanical tests. The scaffold with a porosity of about 78 % was achieved, and at the same time, it had good dimensional stability so that it only lost 43.61 % of its initial weight after 35 days immersing in PBS. Moreover, Gelatin/PU-P showed flexibility, large elongations at break (420 %) and high tensile strength (14 MPa). Finally, biological assessments revealed that the scaffold significantly supported the viability of Adipose-derived mesenchymal stem cells (ADMS). High ALP activity, enhancement in mineralization, and greater expression of osteogenic gene markers in cells grown on the Gelatin/PU-P confirmed the osteoinductivity of the scaffold. These findings suggested that Gelatin/PU-P can be used as a bioactive scaffold for bone tissue engineering.