Multifunctional nanocomposite based on halloysite nanotubes for efficient luminescent bioimaging and magnetic resonance imaging

Abstract

A novel multifunctional halloysite nanotube (HNT)-based Fe₃O₄@HNT-polyethyleneimine-Tip-Eu(dibenzoylmethane)₃ nanocomposite (Fe-HNT-Eu NC) with both photoluminescent and magnetic properties was fabricated by a simple one-step hydrothermal process combined with the coupling grafting method, which exhibited high suspension stability and excellent photophysical behavior. The as-prepared multifunctional Fe-HNT-Eu NC was characterized using various techniques. The results of cell viability assay, cell morphological observation, and in vivo toxicity assay indicated that the NC exhibited excellent biocompatibility over the studied concentration range, suggesting that the obtained Fe-HNT-Eu NC was a suitable material for bioimaging and biological applications in human hepatic adenocarcinoma cells. Furthermore, the biocompatible Fe-HNT-Eu NC displayed superparamagnetic behavior with high saturation magnetization and also functioned as a magnetic resonance imaging (MRI) contrast agent in vitro and in vivo. The results of the MRI tests indicated that the Fe-HNT-Eu NC can significantly decrease the T₂ signal intensity values of the normal liver tissue and thus make the boundary between the normal liver and transplanted cancer more distinct, thus effectively improving the diagnosis effect of cancers.

Keywords:

• halloysite nanotube
• lanthanide complex
• iron oxide
• luminescence
• contrast agent

Acknowledgments

This work was supported in part by the National Natural Science Foundation of China (No 21404033, No 21401046), the Technology Research Project of Henan Province (152102210314), the Foundation of the Social Development Project of Jiangsu (BE2015621), and the Natural Science Foundation of Jiangsu (BK20141122).

Disclosure

The authors report no conflicts of interest in this work.