Degradable mesoporous semimetal antimony nanospheres for near-infrared II multimodal theranostics

Yu Chen,Zhongzheng Yu,Kai Zheng,Qiang Wu,Yaguang Ren,Chengbo Liu,Liwei Liu,Junle Qu,Jun Song,Feifan Zhou,Meng Wang

doi:10.1038/s41467-021-27835-y

Abstract

Metallic and semimetallic mesoporous frameworks are of great importance owing to their unique properties and broad applications. However, semimetallic mesoporous structures cannot be obtained by the traditional template-mediated strategies due to the inevitable hydrolytic reaction of semimetal compounds. Therefore, it is yet challenging to fabricate mesoporous semimetal nanostructures, not even mention controlling their pore sizes. Here we develop a facile and robust selective etching route to synthesize monodispersed mesoporous antimony nanospheres (MSbNSs). The pore sizes of MSbNSs are tunable by carefully controlling the partial oxidation of Sb nuclei and the selective etching of the as-formed Sb2O3. MSbNSs show a wide absorption from visible to second near-infrared (NIR-II) region. Moreover, PEGylated MSbNSs are degradable and the degradation mechanism is further explained. The NIR-II photothermal performance of MSbNSs is promising with a high photothermal conversion efficiency of ~44% and intensive NIR-II photoacoustic signal. MSbNSs show potential as multifunctional nanomedicines for NIR-II photoacoustic imaging guided synergistic photothermal/chemo therapy in vivo. Our selective etching process would contribute to the development of various semimetallic mesoporous structures and efficient multimodal nanoplatforms for theranostics.

Highlights

Metallic and semimetallic mesoporous frameworks are of great importance owing to their unique properties and broad applications
Semimetal-based photothermal agents (PTAs) can absorb the energy of NIR-II light and convert it to heat for photothermal therapy (PTT), and simultaneously generate photoacoustic signals for deep-tissue photoacoustic imaging (PAI)[32,33,34,35,36]
The pore sizes of mesoporous Sb nanospheres (MSbNSs) are tunable by carefully controlling the oxidative degree of Sb nuclei and the selective etching of the as-formed Sb2O3

Summary

Introduction

Metallic and semimetallic mesoporous frameworks are of great importance owing to their unique properties and broad applications. MSbNSs show potential as multifunctional nanomedicines for NIR-II photoacoustic imaging guided synergistic photothermal/chemo therapy in vivo. Antimony (Sb) nanomaterials have been demonstrated to have a wide absorption range from visible to NIR-II region, remarkable photothermal conversion efficiency (PTCE) and intensive photoacoustic signal in the first near-infrared (NIR-I, 700–1000 nm) region[37,38,39,40]. The photothermal degradation mechanism of MSbNSs is proposed, simulated and analyzed Based on these findings, MSbNSs-based multifunctional nanomedicines are successfully constructed and presented for NIR-II PAI guided synergistic photothermal/chemo therapy in vivo. Our approach of selective etching would contribute to the development of more types of semimetallic mesoporous nanostructures and more multimodal theranostics by loading different drugs, antigens or mRNAs for multifunctional chemotherapy, immunotherapy or gene therapy with NIR-II guided PAI and PTT

Methods

Results

Conclusion