Integrating Fluorescence and Magnetic Resonance Imaging in Biocompatible Scaffold for Real‐Time Bone Repair Monitoring and Assessment

Abstract

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, a multifunctional scaffold composed of 3D printed microfilaments and a hydrogel network containing simvastatin (SV), indocyanine green‐loaded superamphiphiles, and aminated ultrasmall superparamagnetic iron oxide nanoparticles (USPIO‐NH2) is fabricated. Both in vitro and in vivo results demonstrate that the as‐prepared scaffold significantly promotes osteogenesis through controlled SV release. The biocomposite scaffold exhibits alkaline phosphatase‐responsive near‐infrared II fluorescence imaging. Meanwhile, USPIO‐NH2 within the co‐crosslinked nanocomposite network enables 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.

Vascularization and Innervation for Bone Tissue Engineering

“…Because of the individual differences of experimental animals, the feedback information is inconsecutive and difficult to reflect the real tissue regeneration. The rapid development of noninvasive imaging technology provides promising methods for continuous and dynamic monitoring of tissue regeneration process. , For an accurate evaluation of the effect of vascularization and innervation for bone regeneration, our group developed bioactive bone scaffolds with multimodal imaging technology to integrated the diagnosis and treatment, which are expected to reveal the synergistic effect of various regenerative elements in bone regeneration, so as to optimize scaffold design and promote bone repair (Figure a) . The aminated ultrasmall superparamagnetic iron oxide (USPIO-NH2) and indocyanine green aggregated superamphiphiles (ICG@Sup) were prepared and loaded into sodium alginate oxide (OSA)/carboxymethyl chitosan (CMCS) with simvastatin (SV) to obtain a composited hydrogel (SV/IU@OC).…”

“…(h) Micro-CT images of tissue section samples in the defect area after 4 and 8 weeks of implantation. Reproduced with permission from ref . Copyright 2024 Wiley-VCH.…”