Polysaccharide/Lipid Nanoconjugates as Alternative Building Blocks for Highly Biocompatible Microcapsules.

Saccharide/lipid nanoconjugates are attractive building blocks for the construction of micro- and nanosized structures because of the roles of glycolipids in human body, courtesy of their intrinsic and functional properties. Herein, nanoconjugates based on dextran and oleic acid (Dex-OA) were synthesized via facile amide-linkage chemistry. The resultant Dex-OA micelles could self-assemble into spherical water-filled microcapsules via a water-in-oil emulsification process. By cross-linking, the microcapsules could be transferred to aqueous media, forming a stable microcapsule dispersion. According to optical and fluorescence microscopy, the microcapsules displayed a spherical morphology, and their synthesis is dependent on the concentration of Dex-OA nanoconjugates. Furthermore, the microcapsules could easily encapsulate and retain fluorescently labeled dextran. This strategy offers a robust and efficient method for the construction of microcapsules from fully natural amphiphilic building blocks with the potential for application in diverse fields such as biomedicine, protocell research, and microreactors.

Self-assembly of stabilized droplets from liquid-liquid phase separation for higher-order structures and functions.

Dynamic microscale droplets produced by liquid-liquid phase separation (LLPS) have emerged as appealing biomaterials due to their remarkable features. However, the instability of droplets limits the construction of population-level structures with collective behaviors. Here we first provide a brief background of droplets in the context of materials properties. Subsequently, we discuss current strategies for stabilizing droplets including physical separation and chemical modulation. We also discuss the recent development of LLPS droplets for various applications such as synthetic cells and biomedical materials. Finally, we give insights on how stabilized droplets can self-assemble into higher-order structures displaying coordinated functions to fully exploit their potentials in bottom-up synthetic biology and biomedical applications.

1-Nitro-4-(4-nitro-phen-oxy)benzene: a second monoclinic polymorph.

In the title compound, C12H8N2O5, the aromatic rings are inclined to one another by 56.14 (7)°. The nitro groups are inclined by to the benzene rings to which they are attached by 3.86 (17) and 9.65 (15)°. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming a three-dimensional structure. The title compound is a new monoclinic polymorph, crystallizing in space group P21/c. The first polymorph crystallized in space group C2/c and the mol-ecule possesses twofold rotation symmetry. Two low-temperature structures of this polymorph (150 K and 100 K, respectively) have been reported [Meciarova et al. (2004). Private Communication (refcode IXOGAD). CCDC, Cambridge, England, and Dey & Desiraju (2005). Chem. Commun. pp. 2486-2488].

A New 2H-2H'/1T Cophase in Polycrystalline MoS2 and MoSe2 Thin Films.

We report on 2H-2H'/1T phase conversion of MoS2 and MoSe2 polycrystalline films grown by thermally assisted conversion. The structural conversion of the transition metal dichalcogenides was successfully carried out by organolithium treatment on chip. As a result we obtained a new 2H-2H'/1T cophase system of the TMDs thin films which was verified by Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The conversion was successfully carried out on selected areas yielding a lateral heterostructure between the pristine 2H phase and the 2H'/1T cophase regions. Scanning electron microscopy and atomic force microscopy revealed changes in the surface morphology and work function of the cophase system in comparison to the pristine films, with a surprisingly sharp lateral interface region.