Redox Trimetallic Nanozyme with Neutral Environment Preference for Brain Injury

Abstract

Metal nanozyme has attracted wide interest for biomedicine, and a highly catalytic material in the physiological environment is highly desired. However, catalytic selectivity of nanozyme is still highly challenging, limiting its wide application. Here, we show a trimetallic (triM) nanozyme with highly catalytic activity and environmental selectivity. Enzyme-mimicked investigations find that the triM system possesses multi-enzyme-mimetic activity for removing reactive oxygen species (ROS) and reactive nitrogen species (RNS), such as 1O2, H2O2, •OH, and •NO. Importantly, triM nanozyme exhibits the significant neutral environment preference for removing the •OH, 1O2, and •NO free radical, indicating its highly catalytic selectivity. The density functional theory (DFT) calculations reveal that triM nanozyme can capture electrons very easily and provides more attraction to reactive oxygen and nitrogen species (RONS) radicals in the neutral environment. In vitro experiments show that triM nanozyme can improve the viability of injured neural cell. In the LPS-induced brain injury model, the superoxide dismutase (SOD) activity and lipid peroxidation can be greatly recovered after triM nanozyme treatment. Moreover, the triM nanozyme treatment can significantly improve the survival rate, neuroinflammation, and reference memory of injured mice. Present work provides a feasible route for improving selectivity of nanozyme in the physiological environment as well as exploring potential applications in brain science.

PEGylated Tantalum Nanoparticles: A Metallic Photoacoustic Contrast Agent for Multiwavelength Imaging of Tumors

“…In addition, the XPS spectrum of PEGylated Ta NPs after incubation with H 2 O 2 , no obvious difference of Ta 4f spectra was found between PEGylated Ta NPs with/without incubation of H 2 O 2 , which may be attributed to the inertness of superficial ultrastable tantalum pentoxide to prevent further oxidation (Figure S8, Supporting Information). Hence, considering that many metal nanoparticles have excellent catalytic properties, the possible ROS scavenging of PEGylated Ta NPs should be attributed to the catalytic decomposition of H 2 O 2 into H 2 O and O 2 , although the detailed mechanism is needed to be revealed in the future study (Figure c) . The ROS scavenging ability can decrease the possibility of the undesired side effect of PEGylated Ta NPs.…”

Nanocatalytic Medicine

“…Pt‐based trimetallic nanocatalysts have been extensively explored in the electrocatalytic ORR due to their lattice distortion and increased density of active sites that enhance their catalytic activities . Very recently, Mu et al demonstrated that PtPdMo trimetallic nanocatalysts could present CAT‐like activities in physiological environment, which is very beneficial for their application in brain disease treatment ( Figure ) . More importantly, different from other reports for nanocatalytic medicine design that mainly concentrate on catalytic “activity,” this work pointed out that “selectivity” is also crucial in tailoring nanocatalysts for their application in specific biological milieu.…”

“…e) Stable structures of these small radical units on the top of segment. a–e) Reproduced with permission . Copyright 2019, American Chemical Society.…”

Antioxidants and Nanotechnology: Promises and Limits of Potentially Disruptive Approaches in the Treatment of Central Nervous System Diseases

“…Mu et al instead developed a trimetallic (triM) nanozyme with multienzyme‐mimetic activity as efficient scavenger of reactive oxygen species and reactive nitrogen species (RNS) in brain thraumatic injuries ( Figure ) …”

“…Trimetallic nanozymes (TriM nanozyme) scavenging properties against ROS and RNS, with higher activity in neutral environment, and their action in repairing brain injury. Reproduced with permission . Copyright 2019, American Chemical Society.…”