Synthesis of iridium-based nanocomposite with catalase activity for cancer phototherapy

Hang Wu,Shige Wang,Qi Jiang,Mengmeng Xie,Zhewei Fei,Keyi Luo,Jiulong Zhao,Chunping Zhu

doi:10.1186/s12951-021-00948-8

Abstract

The combination of photothermal therapy (PTT) and photodynamic therapy (PDT) has attracted attention due to its enhanced tumor therapy effect. This study proposes a novel nanoenzyme-based theranostic nanoplatform, IrO2@MSN@PDA-BSA(Ce6), for the combined PTT and PDT of tumors. IrO2 was prepared by a simple hydrolysis method and coated with a thin layer of mesoporous silica (MSN) to facilitate the physical adsorption of Chlorin e6 (Ce6). The PDA coating and IrO2 NPs of the nanoplatform demonstrated an improved photothermal conversion efficiency of 29.8% under NIR irradiation. Further, the Ce6 loading imparts materials with the ability to produce reactive oxygen species (ROS) under 660 nm NIR laser irradiation. It was also proved that the IrO2 NPs could catalyze the hydrogen peroxide (H2O2) in the tumor microenvironment (TME) to generate endogenous oxygen (O2), thereby enhancing the efficiency of PDT. The in vitro and in vivo experiments indicated that the nanocomposite was highly biocompatible and could produce a satisfactory tumor therapeutic effect. Thus, the findings of the present study demonstrate the viability of using theranostic nanoenzymes for translational medicine.

Highlights

Cancer is currently one of the major obstacles preventing the reduction of the global mortality rate [1, 2]
We can conclude that NPs have a certain degree of aggregation, which is attributed to the interaction between the PDA and bovine serum albumin (BSA) that were grafted onto the NPs
The results indicated that the IrO2@MSN@PDA-BSA NPs had a high specific surface area (149.6521 m2/g) and large pore volume (0.2 c m3/g)

Summary

Introduction

Cancer is currently one of the major obstacles preventing the reduction of the global mortality rate [1, 2]. Thereafter, the reaction products were centrifuged at 12,000 rpm for 8 min to obtain IrO2@ MSN@PDA-BSA(Ce6) NPs. The supernatant containing excess Ce6 was carefully collected for the loading amount calculation of Ce6. In details, IrO2@MSN@PDA-BSA (200 μg/mL) NPs were incubated in PBS solutions at different pH values (6.0 and 7.4) containing 500 μM H2O2.

Results

Conclusion