Manganese‐Based Functional Nanoplatforms: Nanosynthetic Construction, Physiochemical Property, and Theranostic Applicability

Abstract

Transition metal‐based nanoparticles have shown their broad applications in versatile biomedical applications. Although traditional iron‐based nanoparticles have been extensively explored in biomedicine, transition metal manganese (Mn)‐based nanoparticulate systems have emerged as a multifunctional nanoplatform with their intrinsic physiochemical property and biological effect for satisfying the strict biomedical requirements. This comprehensive review focuses on recent progress of Mn‐based functional nanoplatforms in biomedicine with the particular discussion on their elaborate construction, physiochemical property, and theranostic applicability. Several Mn‐based nanosystems are discussed in detail, including solid/hollow MnOx nanoparticles, 2D MnOx nanosheets, MnOx‐silica/mesoporous silica nanoparticles, MnOx‐Fe3O4 nanoparticles, MnOx‐Au, MnOx‐fluorescent nanoparticles, Mn‐based organic composite nanosystem, and some specific/unique Mn‐based nanocomposites. Their versatile biomedical applications include pH/reducing‐responsive T1‐weighted positive magnetic resonance imaging, controlled drug loading/delivery/release, protection of neurological disorder, photothermal hyperthermia, photodynamic therapy, chemodynamic therapy, alleviation of tumor hypoxia, immunotherapy, and some specific synergistic therapies, which are based on their disintegration behavior under the mildly acidic/reducing condition, multiple enzyme‐mimicking activity, catalytic‐triggering Fenton reaction, etc. The biological effects and biocompatibility of these Mn‐based nanosystems are also discussed, accompanied with a discussion on challenges/critical issues and an outlook on the future developments and clinical‐translation potentials of these intriguing Mn‐based functional nanoplatforms.

The Coppery Age: Copper (Cu)‐Involved Nanotheranostics

“…exploited nanomaterials in theranostic nanomedicine, among which a myriad of iron (Fe)-involved and manganese (Mn)composed nanosystems exert the specific function in disease treatment based on their magnetic/paramagnetic property, intrinsic microenvironment-responsive behavior, and high biocompatibility, as reflected by thousands of publications regarding these two transitional metal element-based biomaterial nanosystems. [30][31][32][33][34][35] Alternatively, copper ions (Cu 2+ ) are the bioactive components with the specific capability for promoting angiogenesis, which is originated from their performance on stabilizing the expression of hypoxia-inducible factor (HIF-1 ) and secretion of vascular endothelial growth factor (VEGF), further enhancing the recruitment and differentiation of cells during the blood vessel-producing procedure. [36][37][38][39][40][41][42] It has been fully revealed that Cu ions can facilitate the cell migration, angiogenesis, and collagen deposition for the specific biomedical implementation on accelerating wound healing.…”

“…[ 26–29 ] Transitional metal element‐involved nanosystems are one of the most representative and exploited nanomaterials in theranostic nanomedicine, among which a myriad of iron (Fe)‐involved and manganese (Mn)‐composed nanosystems exert the specific function in disease treatment based on their magnetic/paramagnetic property, intrinsic microenvironment‐responsive behavior, and high biocompatibility, as reflected by thousands of publications regarding these two transitional metal element‐based biomaterial nanosystems. [ 30–35 ]…”

External and Internal Stimuli-Responsive Metallic Nanotherapeutics for Enhanced Anticancer Therapy

“…Tri-therapeutic strategies have successfully eliminated tumors both in vitro and in vivo (Curcio et al, 2019 ). Similarly, other MNPs, including Mo, Pd, Pt, Mn, and Bi nanoparticles, have been extensively investigated as excellent phototherapy and imaging agents, which can be used in clinical studies based on their biocompatible behaviors (Badrigilan et al, 2020 ; Guo et al, 2020b ; Jiang et al, 2020 ; Qian et al, 2020 ).…”

Chemodynamic nanomaterials for cancer theranostics

“…Manganese-based nanomaterials can release manganese ions to catalyze Fenton-like reactions, making them widely used in cancer diagnostics and therapeutics [ 96 – 98 ]. Owing to the enhanced spin–spin relaxation of manganese, manganese-based nanomaterials also exhibit low toxicity, tumor targeting ability, and potential magnetic resonance (MR) imaging contrast [ 99 ].…”