Fluorescent, DNA-stabilized silver clusters are generating growing interest as selective sensors and biolabels, but the origins for their wideranging, sequence-tuned colors are obscure. On page 2797, Elisabeth Gwinn and co-workers report that compositionally pure complexes with 10–24 silver atoms, formed on a variety of DNA strands, all contain both neutral and cationic silver. Optical properties indicate a nanorod geometry, with color reflecting the length of a silver atom chain in the nanorod core.
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Generally, damaged polymeric materials do not return to their original shape and strength. If the damaged materials can recover spontaneously, material consumption can be minimized. Polymeric materials cross-linked with a hostguest interaction successfully showed a selfhealing property, as reported by Akira Harada and co-workers on page 2849. The authors choose cyclodextrin-host and hydrocarbon guest moieties to obtain self-healing materials. When cutting the material, cooperative host–guest complexation on the cut surfaces should effectively adhere to each other and recover the material strength.
Organic/metal nanowire heterostructures are prepared by embedding Ag nanowire branches in organic microwire trunks during the self-assembly in liquid phase. The formation of exciton polaritons in organic wire under the excitation greatly improves the plasmon launch efficiency due to the direct photon-plasmon coupling. The light signals inputted from the organic waveguide can be selectively out-coupled to the predetermined subwavelength Ag nanowires. These organic/metal nanowire heterostructures are potentially applied in integrated photonic circuits as underlying optical multiplexers. Further details can be found in the article by Jiannian Yao, Yong Sheng Zhao, and co-workers on page 2784.