Synthesis of chiral silver nanoclusters capped with small molecules

We report a route of synthesizing water-soluble chiral luminescent Ag nanoclusters (NCs) using d-penicillium and l-penicillium as stabilizer agents by photo-reduction method. These Ag NCs exhibit characteristic of tunable fluorescence from 603 nm to 640 nm, controllable Cotton effects or circular dichroism (CD) signals with an opposite sign (mirror–image relationship) in metal-based electronic transition regions by varying irradiating time and are stable under ambient conditions. The hemolysis results show that the prepared Ag NCs are better biocompatibility compared with that of CdTe quantum dots (QDs). The stability, chirality, biocompatibility and fluorescent properties of these Ag NCs are likely to find widespread applications in bioimaging, chemical and biosensing, and also possibly in asymmetry catalysis.

Fluorescence spectra of the Ag nanocluster after different periods of UV irradiation: 1) 20, 2) 30, 3) 40, 4) 50, and 5) 70 min.Figure optionsDownload as PowerPoint slideHighlights
► The Ag NCs are prepared using chiral penicillium as ligand and UV light to reduce a silver salt.
► The Ag NCs exhibit defined emission wavelength and controllable chirality by varying irradiating time.
► The hemolysis results show that the Ag NCs are better biocompatibility compared with that of CdTe QDs.