The synthesis of large lattice mismatch metal-semiconductor core-shell hetero-nanostructures remains challenging, and thus the corresponding optical properties are seldom discussed. Here, we report the gold-nanorodseeded growth of Au-CdS core-shell hetero-nanorods by employing Ag 2 S as an interim layer that favors CdS shell formation through a cation-exchange process, and the subsequent CdS growth, which can form complete coreshell structures with controllable shell thickness. Exciton-plasmon interactions observed in the Au-CdS nanorods induce shell thickness-tailored and red-shifted longitudinal surface plasmon resonance and quenched CdS luminescence under ultraviolet light excitation. Furthermore, the Au-CdS nanorods demonstrate an enhanced and plasmon-governed two-photon luminescence under near-infrared pulsed laser excitation. The approach has potential for the preparation of other metal-semiconductor hetero-nanomaterials with complete core-shell structures, and these Au-CdS nanorods may open up intriguing new possibilities at the interface of optics and electronics.

Because of their facile preparation, small size (<100 nm), programmable design, and biocompatibility, lipid-based DNA micelles show enormous potential as a tool to monitor biological events and treat human diseases. However, their structural stability in biological matrices suffers from spatiotemporal variability, thus limiting their in vivo use. Herein, we have engineered stability-tunable DNA micelle flares using photocontrollable dissociation of intermolecular G-quadruplexes, which confers DNA micelle flares with robust structural stability against disruption by serum albumin. However, once exposed to light, the G-quadruplex formation is blocked by strand hybridization, resulting in the loss of stability in the presence of serum albumin and subsequent cellular uptake. This programmable regulation to stabilize lipid-based micelles in the presence of fatty-acid-binding serum albumin should further the development of biocompatible DNA micelles for in vivo applications.