Black phosphorus nanosheets for rapid microRNA detection.

Herein, for the first time, a sensitive sensing platform for rapid detection of microRNA was developed by employing black phosphorus nanosheets as the fluorescence quenching material. The biosensor displayed a good linear response to microRNA ranging from 10 nM to 1000 nM. Moreover, the biosensor could distinguish triple nucleotide polymorphism.

Au-Cu(2-x)Se heterodimer nanoparticles with broad localized surface plasmon resonance as contrast agents for deep tissue imaging.

We report a new type of heterogeneous nanoparticles (NPs) composed of a heavily doped semiconductor domain (Cu2-xSe) and a metal domain (Au), which exhibit a broad localized surface plasmon resonance (LSPR) across visible and near-infrared (NIR) wavelengths, arising from interactions between the two nanocrystal domains. We demonstrate both in vivo photoacoustic imaging and in vitro dark field imaging, using the broad LSPR in Cu2-xSe-Au hybrid NPs to achieve contrast at different wavelengths. The high photoacoustic imaging depth achieved, up to 17 mm, shows that these novel contrast agents could be clinically relevant. More broadly, this work demonstrates a new strategy for tuning LSPR absorbance by engineering the density of free charge carriers in two interacting domains.