Highly Sensitive and Selective Detection of Nanomolar Ferric Ions Using Dopamine Functionalized Graphene Quantum Dots

Facile and scalable preparation of highly luminescent N,S co-doped graphene quantum dots and their application for parallel detection of multiple metal ions

New and bright N,S co-doped GQDs are synthesized and serve as fluorescence probes for parallel and selective detection of Fe³⁺, Cu²⁺ and Ag⁺ ions in biological and environmental samples.

Hydrothermal synthesis of polyethylenimine-protected high luminescent Pt-nanoclusters and their application to the detection of nitroimidazoles

A novel one-step hydrothermal synthesis of highly fluorescent platinum nanoclusters protected by polyethylenimine (Pt-NCs@PEI) is described. The products are characterized well by UV-vis absorption, fluorescence spectra, X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) imaging. The Pt-NCs@PEI possess high quantum yield at 28%, which is the relatively high one among the reported Pt-NCs; especially, the synthesis is in one-step and the reaction time is much shorter (<1 h) than the related methods. In addition, the Pt-NCs@PEI have large Stocks-shift (∼150 nm), high tolerability to the extreme pH and high ionic strengths, and excellent photo-stability under UV-vis irradiation, lay the foundation for the practical bio-applications. Finally, the obtained Pt-NCs@PEI are used to determine trace amount of metronidazole (MTZ) in buffer solution in showing a linear response over a concentration range of 0.25-300 μM and a low detection limit of 0.1 μM. Furthermore, the related investigation on response mechanism will be helpful to design and synthesize new metal nanoclusters as fluorescent probe to detect the trace amount of harmful medicine residuum as nitroimidazoles in human body.