A facile preparation of FePt-loaded few-layer MoS2 nanosheets nanocomposites (F-MoS2-FePt NCs) and their application for colorimetric detection of H2O2 in living cells

Abstract

BackgroundRapid and sensitive detection of H2O2 especially endogenous H2O2 is of great importance for series of industries including disease diagnosis and therapy. In this work, uniform FePt nanoparticles are successfully anchored onto Few-layer molybdenum disulfide nanosheets (F-MoS2 NSs). The powder X-ray diffraction, transmission electron microscopy, UV–Vis spectra and atomic force microscopy were employed to confirm the structure of the obtained nanocomposites (F-MoS2-FePt NCs). The prepared nanocomposites show efficient peroxidase-like catalytic activities verified by catalyzing the peroxidation substrate 4,4′-diamino-3,3′,5,5′-tetramethylbiphenyl (TMB) with the existence of H2O2.ResultsThe optimal conditions of the constructed colorimetric sensing platform is proved as 35 °C and pH 4.2. Under optimal catalytic conditions, the detection limit for H2O2 detection reaches 2.24 μM and the linear ranger is 8 μM to 300 μM. Furthermore, the proposed colorimetric sensing platform was successfully utilized to detect the intracellular H2O2 of cancer cells (MCF-7).ConclusionsThese findings indicated that the F-MoS2-FePt-TMB-H2O2 system provides a potential sensing platform for hydrogen peroxide monitoring in living cells.Electronic supplementary materialThe online version of this article (10.1186/s12951-019-0465-3) contains supplementary material, which is available to authorized users.

Palladium Nanoparticles Stabilized by Lentinan with Enhanced Peroxidase‐like Activity for Sensitive Detection of H2O2

“…HeLa cells were selected as the model cells to verify the feasibility of Pd‐LNT NPs in detecting H 2 O 2 in living cells. Ascorbic acid was chosen as a stimulant agent due to its pro‐oxidation property in high concentration [40–42] …”

“…Ascorbic acid was chosen as a stimulant agent due to its prooxidation property in high concentration. [40][41][42] As shown in Figure 10, the absorbance at 652 nm of other groups was very low, while the corresponding absorbance of Pd-LNT NPs group was 0.270 (2 × 10 5 cells) and 0.478 (4 × 10 5 cells), respectively. It was obvious that when the number of cells increased, the absorbance gradually increased.…”

Yb3+-Doped Two-Dimensional Upconverting Tb-MOF Nanosheets with Luminescence Sensing Properties

“…MOFs are interesting materials with a very flexible structure, abundant building units, and a superior porous surface with tunable functionalization and pore size. , MOFs synthesized by coordination-driven self-assembly of metal ions (or clusters) and organic linkers are widely used in storage and separation, , catalysis, − electrochemistry, − drug delivery, , and chemosensors. − In recent years, luminescent MOF sensors that use the change in the PL properties caused by the interaction between the host and the guest as a visual signal , have attracted the attention of many researchers. However, most of these are three-dimensional (3-D) bulk-size MOFs. − Compared with 3-D MOFs, two-dimensional (2-D) materials have larger lateral sizes and extremely thin longitudinal thicknesses, resulting in larger surface areas and more accessible active sites. ,− Moreover, the 2-D materials can be more stably dispersed in water or other organic solvents, and it is also more conducive to the realization of high-sensitivity and fast-response luminescence sensing. − Besides, several luminescent MOFs with rare-earth ions as the center metal ions have been widely used in the field of luminescence sensing already. ,, However, since the excitation wavelengths of most MOFs are located in the UV region, the weak penetrability and autoluminescence interference limit their applications. Therefore, the NIR responsive MOFs are becoming an emerging research hotspot, and the upconverting luminescence mechanism of rare-earth ions provides a realistic basis for this idea.…”

Magnetically guided theranostics: montmorillonite-based iron/platinum nanoparticles for enhancing in situ MRI contrast and hepatocellular carcinoma treatment

“…Thus, the optimization of contrast medium, such as the superparamagnetic iron-based nanomaterial, has become a critical issue when used as a contrast medium for MRI to detect HCC accurately [ 38 ]. Even if the relative position of cancer cells can be aware by the dark field changes obtained by T2-weighted MRI detection; however, insufficient contrast between dark colors may cause interpretation errors, especially in the liver organ [ 39 ]. This problem has prompted scientists to consider creating new MRI contrast nanocomposites [ 40 , 41 ].…”