Plasmon-enhanced luminescence in novel complex conjugated polymer nanoparticles: publisher's note.

This publisher's note corrects errors in the affiliations in Opt. Lett.42, 3789 (2017).OPLEDP0146-959210.1364/OL.42.003789.

Hybrid Structure of 2D Layered GaTe with Au Nanoparticles for Ultrasensitive Detection of Aromatic Molecules.

Owing to a complex monocline structure and high-density of defects in monocrystalline GaTe, the performance of GaTe-based electronic devices is considerably compromised. Yet, the defects' nature in GaTe could be a merit rather than a shortcoming in other realms. In our work, the density of defects in GaTe films is utilized for a facile decoration of Au nanoparticles (NPs), which allowed us to extend its application potential to the domain of surface enhanced Raman scattering (SERS) for the first time. Two-dimensional (2D) GaTe layered structures are prepared by mechanical exfoliation, and high-density Au NPs are synthesized by immersion of 2D GaTe in HAuCl4 aqueous solution. By varying the immersion time, the sizes and coverage rate of Au NPs on GaTe can be elaborately tuned. Thanks to the defect nature of GaTe, the maximum coverage amounts to 98%. The hereby achieved Au-NPs-2D-GaTe hybrid structure demonstrates outstanding properties as a superior SERS substrate for ultrasensitive detection of R6G aromatic molecules. Remarkably, the enhancement factor reaches up to 1.6 × 104, and the minimum detectable concentration is 10-11 M, undercutting that of recently reported Au-NPs-MoS2 SERS and Au-NPs-graphene SERS substrates which have a similar structure. With superior detection capability and facile preparation, Au-NPs-GaTe SERS substrates can become a perfect choice for the detection of aromatic molecules.

Enhancement of ε-poly-L-lysine synthesis in Streptomyces by exogenous glutathione.

Our previous work indicated that the vigor of Streptomyces decreased at the later stage of ε-poly-L-lysine (ε-PL) fermentation. In this study, we observed that the level of reactive oxygen species (ROS) in vivo increased sharply after 24 h, and the addition of an antioxidant glutathione (GSH) before this increase in ROS stimulated ε-PL synthesis in shake-flask fermentation. The enhancement of ε-PL production by GSH was further verified in batch and fed-batch fermentations. On a 5-l fermenter scale, the highest increasement was 68.8% in batch fermentation and the highest ε-PL level was 46.5 g l- 1 in fed-batch fermentation. The RT-qPCR analysis showed that the transcriptional level of the catalase gene was down-regulated, and the decrease in cell activity was alleviated by the addition of GSH. The results revealed that exogenous antioxidant might maintain the cell vigor by reducing the excess ROS which provided a novel approach to regulate ε-PL synthesis.

Plasmon-enhanced luminescence in novel complex conjugated polymer nanoparticles.

A core-shell structure of novel complex conjugated polymer nanoparticles (CPNs) consisting of poly(2-methoxy,5-(2'-ethylhexyloxy)-1,4-phenylenevinylene), polyethyleneimine (PEI) is developed. PEI is used to construct CPN@PEI core-shell structure through electrostatic attraction, and shell thickness can be controlled by PEI. Small Au-Ag alloy nanoparticles (ANPs) are then inserted into CPN@PEI core-shell structure to plasmonically tune luminescence properties. The coupling structure with double polymer core-shell CPN@PEI and ANPs presents unique luminescent characters, and maximum luminescence enhancement is realized when shell thickness is 8.6 nm. The strategies taking polymer as shell material in construction of core-shell complex CPNs and tuning optical properties by ANPs shall have significant values in applications of CPNs as probes and fluorescent tags in biological science.