Mesoporous silica nanoparticles prepared by organic template-driven synthesis have been successfully explored as carriers of the drug-derivate green luminescent complex of terbium (III) with the nonsteroidal anti-inflammatory drug ketoprofen. The terbium (III) complex was synthesized by reacting ketoprofen sodium salt with terbium (III) chloride, which was further adsorbed onto the surface of mesoporous nanoparticles with a mean particle size of 47 ± 4 nm and pore size of 11 nm. The incorporation of the complex into mesoporous silica nanoparticles was tracked by the decrease in the surface area and pore size of the nanoparticles, and successfully demonstrated by substantial changes in the adsorption isotherms and thermal and vibrational spectroscopy results. The cytotoxicity assay and confocal microscopy have shown that the novel luminescent nanohybrid presents high cell viability and the characteristic terbium (III) emission can be assessed through two-photon excitation, which paves the way for bioimaging applications in nanomedicine.

Photoluminescence (PL) of high-density GaAs nanowires (NWs) encapsulated by a double AlGaAs/GaAs shell is studied. Two lines are found and assigned to the radiative recombinations of photoexcited electrons confined in the center of the GaAs core and at the heteroboundary between the outer GaAs shell and the inner AlGaAs one with the holes in the core and the holes confined at the heteroboundary between the core and the inner AlGaAs shell. The simple model, based on representation of the valence band structure using two levels, well accounts for the observed temperature dependence of the integrated photoluminescence intensities. The proposed double shell structure with tunneling transparent inner shell sets conditions for easy control of the emission energy of the heterostructured nanowires.

Time-resolved photoluminescence was employed to study electron-hole dynamics in radial heterostructured GaAs/AlGaAs/GaAs core/inner shell/outer shell nanowires. It was found that impurity random potential results in a red shift of the recombination time maximum with respect to the photoluminescence peak energy.