Masking the Peroxidase‐Like Activity of the Molybdenum Disulfide Nanozyme Enables Label‐Free Lipase Detection

Abstract

Two-dimensional MoS nanoparticles (2D-nps) exhibit artificial enzyme properties that can be regulated at bio-nanointerfaces. We discovered that protein lipase is able to tune the peroxidase-like activity of MoS 2D-nps, offering low-nanomolar, label-free detection and identification in samples with unknown identity. The inhibition of the peroxidase-like activity of the MoS 2D-nps was demonstrated to be concentration dependent, and as low as 5 nm lipase was detected with this approach. The results were compared with those obtained with several other proteins that did not display any significant interference with the nanozyme behavior of the MoS 2D-nps. This unique response of lipase was characterized and exploited for the successful identification of lipase in six unknown samples by using qualitative visual inspection and a quantitative statistical analysis method. The developed methodology in this approach is noteworthy for many aspects; MoS 2D-nps are neither labeled with a signaling moiety nor modified with any ligands for signal readout. Only the intrinsic nanozyme activity of the MoS 2D-nps is exploited for this detection approach. No analytical equipment is necessary for the visual detection of lipase. The synthesis of the water-soluble MoS 2D-nps is low costing and can be performed in bulk scale. Exploring the properties of 2D-nps and their interactions with biological materials reveals highly interesting yet instrumental features that offer the development of novel bioanalytical approaches.

Regulation of the Peroxidase‐Like Activity of nGO, MoS2 and WS2 Nanozymes by Using Metal Cations

“…Regulation of nanozyme activity with chemical or biological modifications is an ongoing effort for improving the enzymatic reaction. Derivatization of nanozymes or the reaction environment with oligonucleotides, [22,23] ions, [24] proteins, [16] other nanoparticles [25] can regulate the enzymatic activity constructively or destructively. We have observed interference of metal ions with the peroxidase activity of 2D nanozymes.…”

“…Similar to many natural enzymes, nanozymes can be vulnerable to composition of a reaction medium [16,17] . Metal ions are often unavoidable part of a sample matrix and their effects on the enzyme‐catalyzed reactions have been documented [18,19] .…”

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

“…In addition, the Mo-based nanozymes can be used to detect reductive small biomolecules such as GSH, Cys, vitamin B1, and lipase, which can inhibit the enzyme-like activity of nanozymes in the presence of dual substrates such as TMB and H 2 O 2 (Figure 8C). 79,94,108,109 By monitoring the degree of color fading of organic substrates, these reductive small biomolecules can be quantitatively detected.…”

Antioxidant Materials Based on 2D Nanostructures: A Review on Recent Progresses

“…This novel material acted as a tri-enzymatic mimic with catalase, peroxidase and oxidase activity ( Figure 7). Later, Nandu et al showed that out of many proteins, lipase selectively masked the peroxidase activity of 2D MoS 2 [39], as indicated by the increasing K m values, i.e., decreasing affinity towards H 2 O 2 . The v max value was also decreased by more than 94% in the presence of lipase.…”

“…In addition, 2D materials possess unusual electronic, mechanical and optical properties and hence, they can be used as building blocks in a wide range of composites. Concerning the contemporary applications of 2D compounds, they serve as efficient catalysts for water splitting [6][7][8][9][10][11][12][13][14][15] or organic reactions [16][17][18][19][20][21], drug carriers [22][23][24][25][26][27][28][29][30][31], sensors [32][33][34][35][36][37][38][39], materials for energy production and storage [2,15,21,[40][41][42][43][44][45][46][47][48][49] or adsorbers [50]…”