Nitrogen doped porous carbon nanopolyhedra (N-PCNPs) were prepared from direct carbonization of ZIF-8 nanopolyhedra. The N-PCNPs showed uniform morphology, narrow pore-size distribution centered at 3.7 nm, high surface area (2221 m 2 g À1 ) and good electrochemical properties and were used to modify a glassy carbon electrode to electrochemically detect ascorbic acid (AA), dopamine (DA) and uric acid (UA). Compared with the bare GC electrode and reduced graphene oxide modified glassy carbon (rGO/GC) electrode, the N-PCNPs modified GC electrode (N-PCNPs/GC) was found to perform better toward electrocatalytic oxidation of AA, DA and UA. For simultaneous sensing of three analytes, three well-separated voltammetry peaks were obtained using the N-PCNPs/GC electrode in differential pulse voltammetry measurements, and the corresponding peak separations between AA and DA, DA and UA were 228 mV, 124 mV respectively. The linear response ranges for the determination of AA, DA and UA were 80-2000 mM, 0.5-30 mM and 4-50 mM, respectively, and the detection limits (S/N ¼ 3) were 740 nM, 11 nM and 21 nM, respectively. Furthermore, the N-PCNPs/GC electrode showed good reproducibility and stability. The attractive features of N-PCNPs provided potential applications in the simultaneous determination of UA, AA and DA.
We report a simple and facile approach for the synthesis of β-cyclodextrin non-covalently functionalized single-walled carbon nanotubes bridged by 3,4,9,10-perylene tetracarboxylic acid (β-CD-PTCA-SWCNTs). Fourier transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, Raman spectroscopy and electrochemical methods were used to characterize the as-prepared functionalized SWCNTs. Furthermore, the β-CD-PTCA-SWCNTs were applied successfully to detect 9-anthracenecarboxylic acid (9-ACA, one derivative of polycyclic aromatic hydrocarbons) by electrochemical methods. The results show that the oxidation peak current of 9-ACA on β-CD-PTCA-SWCNTs modified glassy carbon (GC) electrode is 4.0 and 31.2 times higher than that at the SWCNTs/GC and bare GC electrodes, respectively. The proposed modified electrode has a linear response range of 2.00 to 140.00 nM with a detection limit of 0.65 nM (S/N = 3) towards 9-ACA, which is due to the synergic effects of the SWCNTs (e.g. their good electrochemical properties and large surface area) and β-CD (e.g. a hydrophilic external surface and a high supramolecular recognition and enrichment capability).
Naphthol isomers, including α-naphthol (α-NAP) and β-naphthol (β-NAP), are used widely in various fields and are harmful to the environment and human health. The qualitative and quantitative determination of naphthol isomers is therefore of great significance. Herein, β-cyclodextrin (β-CD)-platinum nanoparticles (Pt NPs)/graphene nanosheets (GNs) nanohybrids (β-CD-PtNPs/GNs) were prepared for the first time using a simple wet chemical method and characterized by atomic force microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and electrochemical methods, and then applied successfully in the ultrasensitive electrochemical detection of naphthol isomers. The results show that the oxidation peak currents of naphthol isomers obtained at the glassy carbon (GC) electrode modified with β-CD-PtNPs/GNs are much higher than those at the β-CD/GNs/GC, PtNPs/GNs/GC, GNs/GC, and bare GC electrodes. Additionally, compared with other electrochemical sensors developed previously, the proposed electrode results in improved detection limits of about one order of magnitude for α-NAP (0.23 nM) and three orders of magnitude for β -NAP (0.37 nM).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.