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Golgi apparatus (GA) is the hub of intracellular trafficking, but selectively targeting GA remains a challenge. We show an unconventional type of peptide thioesters, consisting of an aminoethyl thioester and being substrates of thioesterases, for instantly targeting GA of cells. The peptide thioesters, above or below their critical micelle concentrations, enter cells mainly via caveolin-mediated endocytosis or macropinocytosis, respectively. After being hydrolyzed by GA-associated thioesterases, the resulting thiopeptides form dimers and accumulate in the GA. After saturating GA, the thiopeptides enrich in endoplasmic reticulum (ER). Their buildup in ER and GA disrupts protein trafficking, thus lead to cell death via multiple pathways. The peptide thioesters target Golgi of wide variety of cells, including human, murine, and Drosophila cells. Changing D-diphenylalanine to L-diphenylalanine in the peptide maintains the GA-targeting ability. In addition, targeting GA redirects protein (e.g., NRAS) distribution. This work illustrates a thioesterase responsive and redox active molecular platform for targeting GA and controlling cell fates.

Two-dimensional (2D) semiconductors hold great promise in flexible electronics because of their intrinsic flexibility and high electrical performance. However, the lack of facile synthetic and subsequent device fabrication approaches of high-mobility 2D semiconducting thin films still hinders their practical applications. Here, we developed a facile, rapid, and scalable solution-assisted method for the synthesis of a high-mobility semiconducting oxyselenide (Bi2O2Se) thin film by the selenization and decomposition of a precursor solution of Bi(NO3)3·5H2O. Simply by changing the rotation speed in spin-coating of the precursor solution, the thicknesses of Bi2O2Se thin films can be precisely controlled down to few atomic layers. The as-synthesized Bi2O2Se thin film exhibited a high Hall mobility of ∼74 cm2 V-1 s-1 at room temperature, which is much superior to other 2D thin-film semiconductors such as transition metal dichalcogenides. Remarkably, flexible top-gated Bi2O2Se transistors showed excellent electrical stability under repeated electrical measurements on flat and bent substrates. Furthermore, Bi2O2Se transistor devices on muscovite substrates can be readily transferred onto flexible polyvinyl chloride (PVC) substrates with the help of thermal release tape. The integration of a high-mobility thin-film semiconductor, excellent stability, and easy transfer onto flexible substrates make Bi2O2Se a competitive candidate for future flexible electronics.

We report a general reaction container effect in the nanocasting synthesis of mesoporous metal oxides. The size and shape of the container body in conjunction with simply modifying the container opening accessibility can be used to control the escape rate of water and other gas-phase byproducts in the calcination process, and subsequently affect the nanocrystal growth of the materials inside the mesopore space of the template. In this way, the particle size, mesostructure ordering, and crystallinity of the final product can be systemically controlled. The container effect also explain some of the problems with reproducibility in previously reported results.

A magnesiothermic reduction synthesis approach is reported for direct conversion of SiO(2)/C composite nanostructures to corresponding SiC materials without losing their nanostructure morphologies. Crystalline SiC materials can be obtained by this approach at a temperature as low as 600 degrees C, only approximately half of that applied in the generally used carbothermal reduction and preceramic polymer pyrolysis methods. An ordered hierarchical macro-mesoporous SiC material was synthesized for the first time as a demonstration. This pseudomorphic transformation can be regarded as a general synthesis method for different kinds of SiC nanostructures, and it can also be readily extended to other metal carbide materials as well as TiC.

We demonstrated that the nanostructures comprising silver cores and dense layers of Y(2)O(3):Er separated by a silica shell are an excellent model system to study the interaction between upconversion materials and metals in nanoscale. This architecture allows for versatile control of the Y(2)O(3):Er-metal interaction through control of the silica dielectric spacer thickness and the metal-core size. Finally, the nanoparticles are potentially interesting as fluorescent labels in, for instance (single particle), imaging experiments or bioassays which require low background or tissue penetrating wavelengths.