[Progress in study of nitroimidazole as hypoxia imaging agents in tumor].

Radionuclide hypoxia imaging has become an indispensable core of tumor diagnosis. Nitroimidazole derivatives have been extensively used as the hypoxia imaging agents in preclinical and clinical research. It is the key to design the ideal structure for promising agents.

Systemic delivery of siRNA by hyaluronan-functionalized calcium phosphate nanoparticles for tumor-targeted therapy.

In this study, hyaluronan (HA)-functionalized calcium phosphate nanoparticles (CaP-AHA/siRNA NPs) were developed for an injectable and targetable delivery of siRNA, which were prepared by coating the alendronate-hyaluronan graft polymer (AHA) around the surface of calcium phosphate-siRNA co-precipitates. The prepared CaP-AHA/siRNA NPs had a uniform spherical core-shell morphology with an approximate size of 170 nm and zeta potential of -12 mV. The coating of hydrophilic HA improved the physical stability of nanoparticles over one month due to the strong interactions between phosphonate and calcium.