No abstract

Gold (Au) nanoplates with an average thickness of ∼70nm and several 10μm in edge size have been mass synthesized through a solution-phase method. Structural studies demonstrate that the Au nanoplates are single crystals with (111) planes as two basal surfaces. Fragmentation of Au nanoplates is found when temperature is higher than 450°C. Investigations on the thermal stability of Au nanoplates suggest that the melting and breaking start mainly at the (110) bounded edges, while the (111) surfaces of Au nanoplates show high stability. This work is valuable for Au nanostructures applied at elevated temperatures.

Magnetic targeting is one of the most promising approaches for improving the targeting efficiency by which magnetic drug carriers are directed using external magnetic fields to reach their targets. As a natural magnetic nanoparticle (MNP) of biological origin, the magnetosome is a special “organelle” formed by biomineralization in magnetotactic bacteria (MTB) and is essential for MTB magnetic navigation to respond to geomagnetic fields. The magnetic targeting of magnetosomes, however, can be hindered by the aggregation and precipitation of magnetosomes in water and biological fluid environments due to the strong magnetic attraction between particles. In this study, we constructed a magnetosome-like nanoreactor by introducing MTB Mms6 protein into a reverse micelle system. MNPs synthesized by thermal decomposition exhibit the same crystal morphology and magnetism (high saturation magnetization and low coercivity) as natural magnetosomes but have a smaller particle size. The DSPE-mPEG–coated magnetosome-like MNPs exhibit good monodispersion, penetrating the lesion area of a tumor mouse model to achieve magnetic enrichment by an order of magnitude more than in the control groups, demonstrating great prospects for biomedical magnetic targeting applications.