In situ embedding dual-Fe nanoparticles in synchronously generated carbon for the synergistic integration of magnetic resonance imaging and drug delivery.

Hui Zhang,Yongtai Yang,Xiaofeng Liu,Qianqian Zhang,Yaming Zhou,Yun Ling,Jianping Zhang

doi:10.1039/d0na00714e

Abstract

In situ incorporating versatile magnetic iron nanoparticles into ordered mesoporous carbon (OMC) by means of synthetic methodology for functional integration is a great challenge. Inspired by the phenomenon of uniovular twins in nature, a homometallic [Fe9(μ3-O)4(O3PPh)3(O2CCMe3)13] ({Fe9P3}) cluster was synthesized and used as the ovulum to in situ produce dual-Fe nanoparticle (γ-Fe2O3 and Fe(PO3)3)-functionalized OMC (dual-Fe/OMC). In vitro magnetic resonance imaging (MRI) studies showed a longitudinal relaxation (r1) and transverse relaxation (r2) of 9.74 and 26.59 mM−1 s−1 with a r2/r1 ratio of 2.73 at 0.5 T. The MRI performances were further examined by mouse model with a subcutaneous HeLa tumor. In addition, the low cytotoxicity, considerable loading capacity and delivery of doxorubicin hydrochloride (DOX) were also studied in vitro. These results demonstrate the feasibility of the concept of uniovular twins in the one-pot preparation of dual-Fe/OMC for functional integration.

Highlights

The low cytotoxicity, considerable loading capacity and delivery of doxorubicin hydrochloride (DOX) were studied in vitro. These results demonstrate the feasibility of the concept of uniovular twins in the one-pot preparation of dual-Fe/ordered mesoporous carbon (OMC) for functional integration
Scanning Electron Microscopy (SEM), powder X-ray diffraction (PXRD), and Fourier transform infrared spectroscopy (FT-IR) characterizations demonstrated the successful isolation of the {Fe9P3} cluster (Fig. 1 and S1†)
Thermal gravimetric analysis (Fig. S1c†) and variable-temperature PXRD characterizations showed that there was no obvious weight loss or crystal phase transformation as the temperature increased from 30 to 350 C, indicating an excellent physical property that is capable of avoiding uncontrollable migration before pyrolysis

Summary

Introduction

Integrating magnetic nanoparticles into porous materials is a feasible way to develop theranostic nanomaterials for the combination of magnetic resonance imaging (MRI) and drug delivery systems (DDSs).[1,2,3,4,5] Generally, iron (Fe) or gadolinium (Gd) compounds that possess superparamagnetic or paramagnetic properties are clinical candidates for MRI.[6,7,8,9] As for DDSs, ordered mesoporous carbons (OMCs) are regarded as a kind of promising candidates owing to their large pore volumes, high surface areas and excellent biocompatibility.[10,11,12,13,14] structures in the form of a magnetic core coated by OMCs have been proposed for functional integration.[15,16,17] only one single small magnetic core is not sufficient to produce substantial MRI contrast effect. The HeLa cells were treated with DOX@dual-Fe/OMC-24-600 for different time periods (1 h, 2 h, and 4 h). All of these results suggest that the {Fe9P3} cluster ful lls the requirements of the EISA method in the preparation of dual-Fe/OMC under the concept of uniovular twins.

Results

Conclusion