Integrating Fluorescence and Magnetic Resonance Imaging in Biocompatible Scaffold for Real-time Bone Repair Monitoring and Assessment.

In situ monitoring of bone tissue regeneration progression is critical for the development of bone tissue engineering scaffold. However, engineered scaffolds that can stimulate osteogenic progress and allow for non-invasive monitoring of in vivo bone regeneration simultaneously are rarely reported. Based on a hard-and-soft integration strategy, we fabricated a multifunctional scaffold composed of 3D printed microfilaments and a hydrogel network containing simvastatin (SV), indocyanine green-loaded superamphiphiles (ICG@Sup) and aminated ultrasmall superparamagnetic iron oxide nanoparticles (USPIO-NH 2 ). Both in vitro and in vivo results demonstrated that the as-prepared scaffold significantly promoted osteogenesis through controlled SV release. The biocomposite scaffold exhibited alkaline phosphatase (ALP)-responsive near-infrared II fluorescence imaging. Meanwhile, USPIO-NH 2 within the co-crosslinked nanocomposite network enabled the visualization of scaffold degradation by magnetic resonance imaging. Therefore, the biocomposite scaffold enables or facilitates non-invasive in situ monitoring of neo-bone formation and scaffold degradation processes following osteogenic stimulation, offering a promising strategy to develop theranostic scaffolds for tissue engineering. This article is protected by copyright. All rights reserved.