RESUMO
In this work, we report the synthesis of Cu-Ag bimetallic nanopartiles and g-C3N4 nanosheets decorated on zeolitic imidazolate framework-8 (ZIF-8) to form a Cu-Ag/g-C3N4/ZIF hybrid. The hybrid was synthesized and characterized by Transmission electron microscopy (TEM), Fourier transformed infrared (FTIR), the X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The Cu-Ag/g-C3N4/ZIF hybrid has intrinsic peroxidaselike catalytic activity towards the oxidation of TMB in the presence of H2O2. The situ synthesis of Cu-Ag bimetallic nanopartiles on 2D support such as g-C3N4 nanosheets would significantly enhance the peroxidaselike catalytic properties of individual Cu-Ag bimetallic nanopartiles and the g-C3N4 nanosheets. After loading of Cu-Ag bimetallic nanopartiles and g-C3N4 nanosheets on the ZIF-8, the hybrids exhibited superior peroxidaselike catalytic activity and good recyclability. Then, this method was applied for detecting glucose in human serum, owing the significant potential for detection of metabolites with H2O2-generation reactions.
Assuntos
Materiais Biomiméticos/química , Cobre/química , Glucose/análise , Peróxido de Hidrogênio/química , Estruturas Metalorgânicas/química , Peroxidase/química , Prata/química , Zeolitas/química , Catálise , Colorimetria , OxirreduçãoRESUMO
We developed a sensitive and selective method for detection of 4-Nitrophenol (PNP) using Ag nanoclusters (NCs) as fluorescence probe. Bovine serum albumin (BSA) was used as the template for preparing Ag NCs via wet chemistry. The fluorescence of as-prepared Ag NCs was significantly quenched in the presence of PNP, showing excellent linear relationships between the quenching degree of the fluorescence intensity and the concentrations of PNP in the range of 0.5 µM to 60 µM. The fluorescence quenching mechanism was also investigated. Furthermore, this method was applied for the recognition of PNP in environmental samples.
Assuntos
Fluorescência , Corantes Fluorescentes/química , Nanopartículas Metálicas/química , Nitrofenóis/análise , Soroalbumina Bovina/química , Prata/química , Espectrometria de Fluorescência/métodos , Animais , BovinosRESUMO
Boron and nitrogen codoped carbon dots functionalized with cyclodextrin (ß-CD-N/B-C-dots) were obtained from ß-cyclodextrin. The material displays strong fluorescence (with excitation/emission peak wavelengths of 400/500 nm) and was characterized by UV-vis, transmission electron microscopy and FTIR. If the substrate p-nitrophenylphosphate is enzymatically cleaved by alkaline phosphatase (ALP), a yellow product is formed whose absorption overlaps the excitation spectrum of the ß-CD-N/B-C-dots. Hence, fluorescence is reduced due to an inner filter effect. In additon, the ß-CD cavity offers a pocket for substrate recognition. The findings were used to design a method for the determination of the activity of ALP. It has a working range that extends from 0.003 to 5.5 U·L-1, with a 0.3 mU·L-1 detection limit. The method is fast, simple, inexpensive, and highly sensitive and selective. Graphical abstract Schematic of an inner filter effect based probe for alkaline phosphatase based on the use boron and nitrogen co-doped carbon dots (N/B-C-dots) modified with ß-cyclodextrin (ß-CD). PNPP: p-Nitrophenylphosphate; PNP: p-Nitrophenol anion.
Assuntos
Fosfatase Alcalina/metabolismo , Boro/química , Carbono/química , Ensaios Enzimáticos/métodos , Fluorometria/métodos , Nitrogênio/química , Pontos Quânticos/química , FiltraçãoRESUMO
This essay is to present an improvement on the concentration assay for hemihydrate gypsum in plaster of Paris bandage-Viscose form.