Photoenhanced Oxidase–Peroxidase-like NiCo₂O₄@MnO₂ Nanozymes for Colorimetric Detection of Hydroquinone

Abstract

Artificial oxidase and peroxidase mimics that are based on nanomaterials have drawn enormous attention due to their high stability, high efficiency, and low cost as compared with natural enzymes. Achieving multifunction and further boosting catalytic efficiency are two key directions of future nanozyme development. In this work, NiCo2O4@MnO2 microcubes with p–n junctions were constructed, exhibiting both oxidase- and peroxidase-like activities, capable of catalyzing the oxidation of tetramethylbenzidine (TMB) in the presence of O2 or H2O2. More importantly, such catalytic activity can be dramatically enhanced through illumination due to the in-build p–n junctions and the consequent photoelectric effect. As a prototype, NiCo2O4@MnO2 was utilized in a colorimetric assay to detect trace hydroquinone. An outstanding lowest detection limit of 0.042 μM is achieved, and the recovery in real water samples ranges from 99.87 to 101.10%. The dual enzyme-mimetic and photoenhanced catalytic activities render the nanozyme promising for various applications in sensors and catalysts.

Novel Photoelectrochemical Biosensing Platform Based on a Double Type II CdLa2S4/SnIn4S8/Sb2S3 Ternary Heterojunction as Photoactive Materials and NiCo2O4 Nanospheres as a Photoquencher for CA19-9 Detection

“…20 NiCo 2 O 4 has attracted much attention in the field of catalysis on account of its unique, bimetallic element synergistic effect, 21,22 controllable morphological properties, 23 tunable band gap, and good electron transfer properties compared to single oxides. 24 According to research reports, NiCo 2 O 4 with superior electrochemical performance has been rarely studied in the field of PEC immunosensor. Therefore, p-type NiCo 2 O 4 with a 300 nm core−shell structure has a large specific surface area and can expose more active sites, which also provides a guarantee for its use as a secondary antibody marker in the PEC biosensing platform.…”

“…NiCo 2 O 4 is a typical transition metal oxide with a spinel structure, which has the advantages of low cost, good conductivity, high content, and excellent stability . NiCo 2 O 4 has attracted much attention in the field of catalysis on account of its unique, bimetallic element synergistic effect, , controllable morphological properties, tunable band gap, and good electron transfer properties compared to single oxides . According to research reports, NiCo 2 O 4 with superior electrochemical performance has been rarely studied in the field of PEC immunosensor.…”

Tetrabutylammonium-chloride-glycerol of deep eutectic solvent functionalized MnO2: a novel mimic enzyme for the quantitative and qualitative colorimetric detection of l-cysteine

“…MnO 2 nanosheet, a type of transition metal oxide, has low toxicity and good biocompatibility, rich redox chemistry, and excellent catalytic and oxidase-like activity. Owing to its superior chemical and physi-cal properties, many researchers have combined MnO 2 nanosheets with chem/biosensing techniques for the determination of dopamine, 14 hydroquinone, 15 glutathione, 16 salmonella, 17 etc. More importantly, different from the reported peroxidase mimics for colorimetric sensing, MnO 2 nanosheets represent a label-free colorimetric probe that can oxidize the colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into a blue product (oxTMB), which has a characteristic UV-vis spectrum absorbance at 652 nm, without the addition of H 2 O 2 .…”

Synthesis of SiO2@MnCo2O4 core–shell nanorattles using layered double hydroxide precursors and studies on their peroxidase-like activity

“…31 Ma et al have reported photoinduced peroxidase-like activity of NiCo 2 O 4 @MnO 2 nanozymes. 32 Multi-functional core-shell NPs and nanorattles have been synthesized using various soft chemical synthesis routes. For example, Wang et al have reported the synthesis of MnCo 2 O 4 @MnCo 2 S 4 core-shell nanostructures using the hydrothermal method.…”