An ultimate goal of synthetic DNA motor studies is to mimic natural protein motors in biological systems. Here, we rationally designed a highly integrated and biostable DNA motor system with high potential for living body operation, through simple assembly of a Mn 2+ -dependent DNAzymepowered DNA motor with a degradable MnO 2 nanosheet. The motor system shows outstanding high integration and improved biostability. High integration confers the motor system with the ability to deliver all the core components to the target sites as a whole, thus, enabling precise control of the spatiotemporal distribution of these components and achieving high local concentrations. At the target sites, reduction of the MnO 2 nanosheet by intracellular glutathione (GSH) not only releases the DNA motor, which can then be initiated by the intracellular target, but also produces Mn 2+ in situ to power the autonomous and progressive operation of the DNA motor. Interestingly, the resultant consumption of GSH in turn protects the DNA motor from destruction by physiological GSH, thus, conferring our motor system with improved biostability, reduced false-positive outputs, and consequently, an increased potential to be applied in a living body. As a proof of concept, the highly integrated DNA motor system was demonstrated to work well for amplified imaging detection of survivin mRNA (mRNA), an important tumor biomarker, in both living cancer cells and living tumor-bearing mice. This work reveals concepts and strategies promoting synthetic DNA motor applications in biological systems.

In this communication, a novel reductive dl-mandelic acid loading approach for moisture-stable Mn4+ doped fluorides is reported. After loading dl-mandelic acid, the characteristic luminescence properties of the treated Mn4+ doped potassium hexafluorogermanate remained unchanged, while the moisture-resistance property was significantly enhanced.

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CdMoO(4):Mn nanocrystals with a tetragonal crystal structure were prepared by aqueous coprecipitation method at a low temperature of 2 °C under different pH values. The size of the CdMoO(4):Mn nanocrystals of spherical morphology increases with the Mn dopant concentration from 35 to 55 nm for pH = 4. The morphology could be tuned from nanocrystals to microstructures consisting of smaller nanoparticles by the Mn concentration when the pH value of the precursor was increased to 8. The thermal stability of the luminescence and magnetic properties of the Mn-doped samples also depend on the pH and the doping level. The effects of the pH and dopant on the luminescence and magnetic properties, including magnetic susceptibility and electron paramagnetic resonance, were investigated. This approach contributes to better understanding of aqueous chemistry methods to control the growth of nanocrystals.

A variety of hexagonal sodium yttrium fluoride (NYF) crystals with tunable shapes have been grown, and their up-conversion (UC) emission has been greatly improved after posttreatment in an aqueous solution of NH 4 HF 2 and NaF. The enhancement has been attributed to topotactic ion insertion of sodium cations into the channels of Na 3x Y 2-x F 6 . As sodium-ion insertion continues to occur and the sodium content rises, the up-conversion emission intensity and green-to-red ratio increase up to the saturation level. However, the X-ray diffraction patterns and SEM images suggest that both the [a] MOE Key