Chiroptically active quantum nanonails†

Abstract

In recent years, extensive research efforts have been dedicated to the investigation of CdSe/CdS-based quantum-confined nanostructures, driven by their distinctive properties. The morphologies of these nanostructures have been shown to directly affect their properties, an area which has proven to be an important field of study. Herein, we report a new morphology of CdSe/CdS core–shell heterostructures in the form of a ‘nanonail’ – a modified nanorod-like morphology, in which a distinctive triangular head can be observed at one end of the structure. In-depth studies of this morphology reveal a material with tuneable rod length and width, as well as exceptional photoluminescent properties. Following this, we have demonstrated the ability to induce chiroptical activity via ligand exchange, revealing the important role of the specific morphology, shell thickness and chiral ligand concentration in the effect of ligand induced chirality. In addition, the cellular uptake and cytotoxicity of obtained chiral nanostructures were evaluated on human lung-derived A549 cancer cells, revealing a significant enantioselectivity in biological activity. Finally, analysis on monolayers of the material demonstrate the complete absence of FRET processes. Overall, this CdSe/CdS heterostructure is another tuneable morphology of a very important nanomaterial, one which shows great advantages and a range of potential applications.