Rational Atomic Engineering of Prussian Blue Analogues as Peroxidase Mimetics for Colorimetric Urinalysis of Uric Acid

Abstract

Nanoparticles of Prussian blue (PB) and its cyanometallate structural analogues are validated as multienzyme mimetics, while there remains a need for improved activities of PB-based nanozymes through rational atomic engineering on the species and amount of doping metal. Herein, we find that the doping of a second divalent 3d metal ion (Co 2+ , Ni 2+ , and Cu 2+ ) into the PB framework results in discriminated peroxidase-like activity, by catalyzing the oxidation reaction of 3,3′,5,5′-tetramethylbenzidine (TMB) with H 2 O 2 . The order of the catalyzed reaction generally follows Cu 2+ -doped PB (CuPB) > PB > Co 2+ -doped PB (CoPB) > Ni 2+ -doped PB (NiPB). Besides the atomic preference over Cu doping, the amount of doped Cu 2+ is rationally engineered for the optimization of peroxidase-like activity. By coupling the optimized CuPB nanoparticles with natural uricase, we develop a cascade reaction system for measuring the uric acid level in human urine specimens, the results of which are well correlated with the standard values determined on instrumentation (R 2 = 0.975). Due to the simplicity of the platform and capability of preparing CuPB nanozyme in a large scale, we envisage the method to be translated into urinalysis of uric acid, especially packaged as a type of assay kits for point-of-care testing.

A facile, low-cost bimetallic iron–nickel MOF nanozyme-propelled ratiometric fluorescent sensor for highly sensitive and selective uric acid detection and its smartphone application

“…According to previous studies, UA can be oxidized into allantoin under the catalysis of uricase, accompanied by the production of H 2 O 2 . 44 Moreover, this step could achieve the best performance after incubating at pH 8.5 and 37 °C for 15 min. Based on this principle, the detection of UA was then carried out reasonably.…”

Accelerating the Phosphatase-like Activity of Uio-66-NH2 by Catalytically Inactive Metal Ions and Its Application for Improved Fluorescence Detection of Cardiac Troponin I

“…To date, several strategies have been proposed to improve the intrinsic catalytic activities of nanozymes, such as surface modification, heteroatom doping, size controlling, exogenous energy fields, and adding promotors. ,− Among them, modifying or doping nanozymes with metal ions is a reliable and universal strategy to obtain highly active nanozymes. For example, Fe 3+ , Cu 2+ , Ce 4+ , and Au 3+ have been used to modify or dope carbon-based or metal organic framework (MOF) nanozymes to enhance their peroxidase-like or oxidase-like activities. − Zr 4+ and Ce 4+ have been applied to modify catalytically inactive nanomaterials for obtaining catalytically active nanozymes with high phosphatase-like activity. , It is worth noting that the mentioned metal ions themselves possess enzyme-like activities. This means that the improvement in catalytic activities of the modified nanozymes are foreseeable since the modified or doped metal ions on nanozymes can also serve as catalytic centers to participate in enzyme-like catalytic reactions …”

Dental Caries Management with Antibacterial Silver-Doped Prussian Blue Hydrogel by the Combined Effects of Photothermal Response and Ion Discharge

“…Nanoparticles of PB and its analogues are recognized as effective PTT agents and have been widely used to combat complex diseases such as cancer and neurodegenerative disorders . The doping performances of PB nanocrystals by Mn, Gd, Cu, Cr, and Zn elements have been studied, − yet there has been no direct investigation into the doping of PB by Ag + ions, although PB nanocubes decorated with silver nanoparticles were reported . The AgPB nanoparticles exhibit appreciable photothermal effect, and moreover, the releases of Ag + and Fe 2+/3+ ions occur spontaneously under an 808 nm near-infrared (NIR) laser treatment.…”