Here, we propose a magnetic nanoscale metal–organic framework as a novel quenching material and reveal its quenching–quenching mechanism. It sensitively and selectively binds Hg(ii) and a detection limit of 8 nM.
In this work, we fabricated a metal–organic framework derived magnetic porous carbon (MPC) and with ssDNA achieved specific and efficient recognition of harmful arsenate ions. The detection limit was achieved at 630 pM.
Novel fluorescent biosensor constructed by polyaniline nanoclips (PANCs) embedded with FAM-ssDNA for precise detection of mercury ions (Hg 2 + ). The PANCs was adapted to fabricate by an oxidative template method and characterized via various analytical techniques, namely scanning Electron Microscope (SEM), powder X-ray Diffraction (XRD), Fourier transform infrared (FT-IR), circular dichroism (CD spectra) and fluorescence spectroscopy. Based on the strong adsorption property of PANCs was despite a strong quenching of FAM-ssDNA fluorescence. Furthermore, FAM-ssDNA was a strong surface absorption on the surface of polyaniline nanoclips through non-covalent interaction. The fluorescence intensity decreased denotes the electrons transfer from the nitrogen in polyaniline nanoclips to fluorophore of ssDNA as well as may be photoinduced electron transfer (PET). Meanwhile, the addition of mercury ion into a detection probe, which increases the fluorescence intensity due to the desorption. However, the strong binding ability between mercury ion and thymine of FAM-ss DNA leads to form T-Hg 2 + -T duplex mismatch. These results indicate the significant fluorescence intensity was improved and the Hg 2 + sensor was developed. Interestingly, the sensing probe reached the detection limit at 4 nM with rapid response and showed high selectivity towards mercury ions compared to other metal ions. Furthermore, the polyaniline nanoclips were potentially applied for the real samples.
Herein, Cu–HMT and Ni–HMT were synthesized via a green synthetic method. Cu–HMT possesses formidable peroxidase-mimic activity compared to Ni–HMT. However, the peroxidase-like activity of Cu–HMT was strongly inhibited in the presence of DA.
Herein, we present silver nanoparticle anchored on copper oxide and copper hydroxide (Ag@CuO@Cu(OH)2) by green synthetic approach. Interestingly, as‐obtained Ag@CuO@Cu(OH)2 not only enhances the peroxidase‐like activity but also eliminates oxidase‐like activity. The peroxidase‐like activity was enhanced mainly due to the abundance of Ag+ and Cu2+ vacant states, which populate reactive oxygen species (ROS). This prolonged peroxidase‐like activity of Ag@CuO@Cu(OH)2 was successfully recognized H2O2 and also have long stability and repeatability. The proposed strategy, finding nanozymes with single activity will open a new opportunity to enhance the performance of colorimetric sensors.
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.