A flower-like MoS2-decorated MgFe2O4 nanocomposite: Mimicking peroxidase and colorimetric detection of H2O2 and glucose

Enhanced Peroxidase-Like Activity of MoS2 Quantum Dots Functionalized g-C3N4 Nanosheets towards Colorimetric Detection of H2O2

“…On the basis of the above experimental results and some previous literature [1,2,3,4,23,24,28,29,30,31,32,37,38,39,40], the peroxidase-like catalytic mechanism of MoS 2 @CNNS(30) nanocomposites was proposed, and is illustrated in Scheme 1. It can be seen that the negatively-charged MoS 2 @CNNS(30) nanocomposites could act as the peroxidase mimics, facilitating the electron transfer between TMB and H 2 O 2 in the catalytic oxidation reaction.…”

“…Then, the TMB molecules would donate the lone-pair electrons from the amino groups to the surface of MoS 2 @CNNS(30) nanocomposites, enhancing the density and mobility of electrons on the surface of MoS 2 @CNNS(30), then promoting the electron transfer from MoS 2 @CNNS(30) to H 2 O 2 , and further accelerating the TMB catalytic oxidation reaction rate [4,23,24,28,29,30,31,32,37,38,39,40]. Subsequently, the oxidized intermediate ·O 2 − radicals generated in the reaction between MoS 2 @CNNS(30) and H 2 O 2 via one electron transfer would react with TMB molecules to generate a TMB oxide, leading to the color change of the system from colorless to blue [4,23,24,28,29,30,31,32,37,38,39,40]. The corresponding chemical equation was: 2H2O2+ TMB →boldnormalcatalysts 2H2O + O2 + oxTMB.…”

“…In addition, when the size decreased to less than 10 nm, MoS 2 QDs will exhibit unique extra electrical/optical properties owing to the stronger quantum confinement and edge effects [35,36], further improving its catalytic performance. Moreover, MoS 2 with diverse nanostructures (nanoflakes [25] and nanoparticles [37]) and several MoS 2 -based hybrids [38,39,40] have been reported as enzyme mimetics recently. Thus, on account of the matching energy band structure and nice catalytic performance, MoS 2 QDs is becoming an ideal candidate for coupling with g-C 3 N 4 to facilitate the peroxidase-like ability by promoting the separation and transport of electron-hole pairs.…”

A rapid and ultrasensitive colorimetric biosensor based on aptamer functionalized Au nanoparticles for detection of saxitoxin

“…It has been used to detect proteins, [16][17][18] DNAs, [19][20][21] metal ions, 22,23 and small molecules. [24][25][26][27] To construct Au NPs based colorimetric sensor, a specic molecule is needed to bind with Au NPs, which can specically react with target molecules, and then gets desorbed from Au NPs resulting in the aggregation of Au NPs to induce color change. Here we report an Au NPs-aptamer based sensor, and the aptamer functionalized on Au NPs specically reacts with STX, resulting in the aggregation of Au NPs and the change of the surface plasmon resonance absorption peak, which can be used for the quantitative analysis of STX.…”

Design and Characterization of a Novel Artificial Peroxidase

“…In addition, the catalytic properties of Dh-A-H-E were investigated. Another important advantage of Dh-A-H-E is that its optimal pH is 7.4 and it can exhibit high peroxidase activity at pH 7.0, which can dramatically simplify the procedure of glucose detection [20][21][22]. Thus, an improved method for detecting trace amounts of glucose using Dh-A-H-E was developed.…”