Enhanced bone regeneration and visual monitoring via superparamagnetic iron oxide nanoparticle scaffold in rats

Abstract

A main challenge for use of scaffolds in bone engineering involves non-invasive monitoring in vivo and enhanced bone regeneration. The tissue repair effect of superparamagnetic iron oxide nanoparticles (SPIONs) was demonstrated previously by our group. However, testing in vivo is needed to confirm in vitro results. Here, SPIONs loaded gelatin sponge (GS) was used as a scaffold (SPIONs-GS) and implanted in the incisor sockets of Sprague–Dawley rats. Incisor sockets filled with nothing and filled with GS served as controls. Rats were sacrificed at 2 and 4 weeks. A significant decrease in the signal intensity of T2-weighted magnetic resonance imaging (MRI) in the SPIONs-GS group was noted. Changes in image intensity of scaffolds (indicating scaffold degradation and interaction with host tissues) could be visually monitored over time. Microcomputed tomography showed that the SPIONs-GS group had more newly formed bone (64.44 ± 10.92 vs. 28.1 ± 4.49, p