Dual-emissive fluorescence probes were designed by integrating porphyrin into the frameworks of UiO-66 for ratiometric fluorescence sensing of amoxicillin (AMX). Porphyrin integrated UiO-66 showed dual emission in the blue and red region. AMX resulted in the quenching of blue fluorescence component, attributable to the charge neutralization and hydrogen bonds induced energy transfer. AMX was detected using (F438/F654) as output signals. Two linear relationships were observed (from 10 to 1000 nM and 1 to 100 µM), with a limit of detection of 27 nM. The porphyrin integrated UiO-66 probe was used to detect AMX in practical samples. This work widens the road for the development of dual/multiple emissive fluorescence sensors for analytical applications, providing materials and theoretical supporting for food, environmental, and human safety.
Amoxicillin , Anti-Bacterial Agents , Fluorescent Dyes , Milk , Porphyrins , Spectrometry, Fluorescence , Milk/chemistry , Porphyrins/chemistry , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/chemistry , Amoxicillin/analysis , Amoxicillin/chemistry , Fluorescent Dyes/chemistry , Animals , Spectrometry, Fluorescence/methods , Limit of Detection , Metal-Organic Frameworks/chemistry , Drug Residues/analysis , Food Contamination/analysis
Selective etching is significant for fabrication of novel nanostructures. Here silver ions are introduced to control the lateral etching of gold nanorods by K2PtCl4 in a hot solution, producing a number of dumbbell-like PtAu-Au thin gold nanorods. Silver ions control the selective deposition of the reduced Pt(0) atoms, causing the selective etching of the unprotected Au. The middle diameter of the obtained dumbbell-like nanorods can be adjusted from 12 nm to <10 nm. It is believed that this is an effective method to reduce the diameter of gold nanorods.
Bimetallic nanoframes and nanoboxes of Pd-Rh are synthesized by selective removal of Pd cores from different Pd-Rh nanocubes prepared by a hydrothermal reaction of PdCl2, RhCl3 and HCHO. HCHO in the procedure alters the reaction kinetics and the growth behavior of Pd and Rh, resulting in different nanocubes that determine the following hollow nanostructures, nanoframes or nanoboxes. The catalytic properties of the hollow nanostructures are investigated using the oxidation of o-phenylenediamine (OPDA) to 2,3-diaminophenazine (DAP) as a model reaction. The resulting bimetallic nanoframes and nanoboxes show enhanced conversion efficiencies compared to their solid counterparts. This method offers a convenient way for mass production of bimetallic hollow nanomaterials.
