Synthesis of Surface‐Modification‐Oriented Nanosized Molybdenum Disulfide with High Peroxidase‐Like Catalytic Activity for H₂O₂ and Cholesterol Detection

Abstract

Abnormal H O and cholesterol levels are closely related to many diseases. This work reports a facile process for the synthesis of oxidized glutathione (GSSG)-modified MoS nanosheets (MoS -GSSG NSs). The biocompatible MoS -GSSG NSs have good dispersibility and high affinity to the substrate 3,3',5,5'-tetramethylbenzidine (TMB), which is beneficial for improving peroxidase-like catalytic activity of MoS . The high peroxidase-like activity of MoS -GSSG NSs was applied as a robust nanoplatform for low-cost, rapid, and highly effective colorimetric detection of H O and total/free cholesterol. Moreover, the peroxidase-like catalytic mechanism was studied by the steady-state kinetics method. The catalytic activity was remarkably high at a wide range of pH (2.4-7.0) and temperature values (25-70 °C). The cholesterol was catalyzed by cholesterol oxidase (ChOx) in the presence of O to generate H O , which oxidized TMB to generate a blue-colored product (oxTMB) under the catalysis of MoS -GSSG NSs. The detection limit (DL) of total cholesterol and H O was as low as 5.36 and 0.51 μm, respectively. The linear ranges for detecting cholesterol and H O were from 5.36 to 800 μm and from 0.51 to 50 μm, respectively. This method was also successfully applied to the detection of cholesterol in serum. The detection concentration of total cholesterol was consistent with that of the value detected by the blood biochemical method used in the clinic.

<p>Manganese dioxide nanosheets: from preparation to biomedical applications</p>

“…Amongst them, 2D nanomaterials,61 with ultralarge surface areas and flexible structures, enable their excellent catalytic activity and can be incorporated into the surrounding environment to improve substrate specificity. For instance, graphene oxide has been confirmed to possess intrinsic peroxidase-like activity in the presence of hydrogen peroxide (H 2 O 2 ),62,63 so as to ultrathin graphitic carbon nitride (g-CN)64,65 and molybdenum disulfate nanosheets (MoS 2 NSs),66 which are only pragmatic for use as ex-vivo or in vitro substrates. MnO 2 NSs, a typical 2D nanomaterial, also possess intrinsic oxidase-like activity.…”

The age of bioinspired molybdenum‐involved nanozymes: Synthesis, catalytic mechanisms, and biomedical applications

“…It is worth noting that surface modification of Mo-based nanozymes is often utilized to regulate their physicochemical properties such as size, surface charge, morphology, and composition. 27,[50][51][52] In addition, different surface modifications can affect the enzyme-like catalytic activity of Mo-based nanozymes and make them highly stable and well biocompatible. A number of bottom-up and top-down approaches including exfoliation (e.g., liquid exfoliation, ultrasonic exfoliation, and chemical exfoliation), hydrothermal/solvothermal synthesis, thermal decomposition as well as pulsed laser ablation can be used to synthesize Mo-based nanozymes (Table 1).…”

Magnetic Nanoparticle-Based Ligand Replacement Strategy for Chemical Luminescence Determination of Cholesterol

“…Following the similar concepts, many subtypes of ChOx-based detection assays have been developed. In the last decades, such H 2 O 2 generation reactions have been integrated with nanotechniques that have led to several much advanced nanosensors (Huan et al, 2015;Huang et al, 2018;Ma et al, 2018;Wang et al, 2018;Thakur et al, 2019;Xu et al, 2019;Zhao et al, 2019). Nevertheless, integral drawbacks such as high cost for enzyme manipulation and unexpected denaturation of enzymes during storage have limited their real applications.…”