Tannic Acid-Mediated Synthesis of Flower-Like Mesoporous Mno2 Nanostructures As T1–T2 Dual-Modal Mri Contrast Agents and Dual-Enzyme Mimetic Agents Publisher Pubmed



Sorouri F^{1, 2} ; Gholibegloo E¹ ; Mortezazadeh T³ ; Kiani S² ; Foroumadi A⁴ ; Firoozpour L⁴ ; Khoobi M^{1, 5} Show Affiliations
Source: Scientific Reports Published:2023

Abstract

This study introduces a simple method for preparing a new generation of MnO2 nanomaterials (MNMs) using tannic acid as a template. Two shapes of MnO2 NMs, flower-like M1-MnO2 and near-spherical M2-MnO2, were prepared and compared as dual-active nanozymes and contrast agents in magnetic resonance imaging (MRI). Various parameters, including the crystallinity, morphology, magnetic saturation (Ms), surface functionality, surface area, and porosity of the MNMs were investigated. Flower-like M1-MnO2 NMs were biocompatible and exhibited pH-sensitive oxidase and peroxidase mimetic activity, more potent than near-spherical M2-MnO2. Furthermore, the signal intensity and r1 relaxivity strongly depended on the crystallinity, morphology, pore size, and specific surface area of the synthesized MNMs. Our findings suggest that flower-like M1-MnO2 NM with acceptable dual-enzyme mimetic (oxidase-like and peroxidase-like) and T1 MRI contrast activities could be employed as a promising theranostic system for future purposes. © 2023, Springer Nature Limited.