金属-グラフェン相互作用のその場TEM観察

筑波大学 (University of Tsukuba)201

Direct observation of Pt-terminating carbyne on graphene

Theoretical studies predict that carbynes (single-atomic linear carbon chains) have unique properties that rival those of graphene and carbon nanotubes. However, experimental studies on carbynes are rare due to the lack of reliable and effective means of production. Here, we report a direct observation of carbyne formation and dynamics by in situ transmission electron microscopy. Using Pt atoms on graphene, we succeeded in forming and observing carbynes reproducibly. Free carbon adatoms on graphene were trapped by Pt atoms, which served as nucleation sites for carbyne formation. Each end of the carbyne chain was eventually terminated by a Pt atom, and the Pt-terminating carbyne chains exhibited a variety of straight, curved, and ringed shapes

Hole-Free Phase Plate Energy Filtering Imaging of Graphene: Toward Quantitative Hole-Free Phase Plate Imaging in a TEM

Peer reviewed: YesNRC publication: Ye

Ser/Leu-swapped cell-free translation system constructed with natural/in vitro transcribed-hybrid tRNA set

Abstract The Ser/Leu-swapped genetic code can act as a genetic firewall, mitigating biohazard risks arising from horizontal gene transfer in genetically modified organisms. Our prior work demonstrated the orthogonality of this swapped code to the standard genetic code using a cell-free translation system comprised of 21 in vitro transcribed tRNAs. In this study, to advance this system for protein engineering, we introduce a natural/in vitro transcribed-hybrid tRNA set. This set combines natural tRNAs from Escherichia coli (excluding Ser, Leu, and Tyr) and in vitro transcribed tRNAs, encompassing anticodon-swapped tRNASer GAG and tRNALeu GGA. This approach reduces the number of in vitro transcribed tRNAs required from 21 to only 4. In this optimized system, the production of a model protein, superfolder green fluorescent protein, increases to 3.5-fold. With this hybrid tRNA set, the Ser/Leu-swapped cell-free translation system will stand as a potent tool for protein production with reduced biohazard concerns in future biological endeavors

Hole-Free Phase Plate Energy Filtering Imaging of Graphene: Toward Quantitative Hole-Free Phase Plate Imaging in a TEM

Peer reviewed: YesNRC publication: Ye