Enhanced peroxidase-like activity of AuNPs loaded graphitic carbon nitride nanosheets for colorimetric biosensing

Two-Dimensional Nanomaterials With Enzyme-Like Properties for Biomedical Applications

“…A variety of 0D metal NPs-functionalized 2D NSs have also been reported by different groups, including 0D/2D nanostructured Au/GO (Tao et al, 2013), Au/MOF (Huang et al, 2017a), and Pt/black phosphorus (Ouyang et al, 2018). In recent studies, the in-situ growth method was also adopted by different groups for the synthesis of Pt/h-BN (Ivanova et al, 2019) and "naked" Au NPs on g-C 3 N 4 NSs (Wu et al, 2019), via the reduction of metal precursors on NSs with various reducing agents like NaBH 4 , ascorbic acid, etc. Our group also constructed a variety of 0D/2D heterostructures, including PtAg NPs-decorated MoS 2 NSs through the hydrothermal process (Cai et al, 2016), Pt NPs-covered CuO NSs by NaBH 4 reduction (Wang X. H. et al, 2017), and IrO 2 NPs-modified GO (Sun et al, 2020) and reduced GO (rGO) (Liu X. L. et al, 2019) NSs by electrostatic adsorption/hydrothermal treatment.…”

“…PODs and ODs are a class of known oxidative enzymes in biosystems, which activate H 2 O 2 and O 2 to catalyze the oxidation of respective substrates under mild conditions (Wei and Wang, 2013;Huang et al, 2019;Jiang D. W. et al, 2019). To evaluate the POD-/OD-like activity of 2D NMs, catalytic oxidations of enzymatic chromogenic substrates like 3,3' ,5,5'tetramethylbenzidine (TMB), which are often carried out in acidic media and produce colored products (Equation 1), are chosen as a probe reaction by most researchers (Gao et al, 2007;Song et al, 2010;Tao et al, 2013;Cai et al, 2016Cai et al, , 2018aCai et al, , 2019Huang et al, 2017a;Wang X. H. et al, 2017;Ouyang et al, 2018;Ivanova et al, 2019;Liu X. L. et al, 2019;Wu et al, 2019;Sun et al, 2020). The reaction process is tracked by UV-Vis spectroscopy and the color variation of the reaction solution can be easily observed by naked eyes.…”

“…Recently, the assays for various bioanalytes like small molecules, cancer cells, and ions, have been proposed based on PODlike activities of 2D NMs ( Table 2). As a typical example, the colorimetric assays for glucose have been largely developed based on a host of 2D NMs and their hybrids, including graphene derivatives [e.g., GO (Song et al, 2010), FePd/rGO (Yang et al, 2019)], TMDs [e.g., MoS 2 (Lin et al, 2014a), WS 2 (Lin et al, 2014b), WSe 2 , VS 2 (Huang et al, 2018)] and their hybrids [e.g., PtAg/MoS 2 (Cai et al, 2016)], LDHs [e.g., NiFe (Zhan et al, 2018)], and their hybrids [e.g., CeO 2 /CoFe (Yang et al, 2020)], g-C 3 N 4 (Lin et al, 2014c) and its hybrids [e.g., Au/g-C 3 N 4 (Wu et al, 2019), Pd/g-C 3 N 4 (Zhang W. C. et al, 2019), Fe/g-C 3 N 4 (Tian et al, 2013), and AuNi/g-C 3 N 4 (Darabdhara et al, 2019)], and metallic NSs-based hybrids [e.g., Au/Pd and Pt/Pd (Wei et al, 2015)].…”

Ionic liquid coated zerovalent manganese nanoparticles with stabilized and enhanced peroxidase-like catalytic activity for colorimetric detection of hydrogen peroxide

“…Hydrogen peroxide is considered to be a significant mediator in food, clinical, industrial, pharmaceutical, and environmental analyses [4]. Many analytical techniques were widely utilized for the detection of hydrogen peroxide such as electrochemical [5][6][7][8][9][10][11][12][13][14], titrimetry [15], fluorescence [16,17], and colorimetric [18][19][20][21][22][23][24][25][26]. In comparison with other reported methods, there are considerable advantages of colorimetric detection of various analytes over other conventional sensing techniques e.g., costeffectiveness, facile and reliable method, and practicability and quick response.…”

A Colorimetric Assay for the Detection of Glucose and H2O2 Based on Cu-Ag/g-C3N4/ZIF Hybrids with Superior Peroxidase Mimetic Activity

“…Nanozymes have attracted increasing attention in the past decades in the field of catalysis because of their fantastic advantages, including low cost, facile synthesis, excellent stability and are easy to manipulate in optical sensing [ 1 , 2 ]. After the Fe 3 O 4 nanoparticles was first reported as the peroxidaselike nanoenzyme to catalyze 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H 2 O 2 to produce a blue color compound 3,3′,5,5′-tetramethylbenzidine diimine (TMBDI) [ 3 ], different kinds of nanozymes such as carbon based nanomaterials [ 4 ], metal nanoparticles [ 5 , 6 ], metal oxides [ 7 , 8 ] and metal oxide nanocomposites [ 9 , 10 ] have been discovered to replace natural enzymes.…”