Heterodimers made of metal-organic frameworks and upconversion nanoparticles for bioimaging and pH-responsive dual-drug delivery.

Developing multifunctional nanocomposites for a pH-responsive controlled dual-drug delivery is still a huge challenge. Herein, we report a gentle and simple method for growing metal-organic frameworks (MOFs) that can load two anticancer drugs, namely DOX and 5-FU (doxorubicin and 5-fluorouracil), on the surface of upconversion nanoparticles (UCNPs) by the reactions of Schiff bases and electrostatic adsorption. The resulting pH-responsive UCMOFs@D@5 nanosystem showed effective dual-drug release by the cleavage of chemical bonds and the disruption of the MOF structure under acidic conditions.

Enhanced red emission from BaMoO : Eu by Bi co-doping.

A series of Bi ,Eu -doped BaMoO phosphors was synthesized using a hydrothermal method. The crystal structure, morphology and optical properties of the phosphors were studied using X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence (PL) measurements. Three different particle morphologies were detected in the SEM observation.