Subcellular imaging and diagnosis of cancer using engineered nanoparticles

Hypoxia-responsive nanomaterials for tumor imaging and therapy

Hypoxia is an important component of tumor microenvironment and plays a pivotal role in cancer progression. With the distinctive physiochemical properties and biological effects, various nanoparticles targeting hypoxia had raised great interest in cancer imaging, drug delivery, and gene therapy during the last decade. In the current review, we provided a comprehensive view on the latest progress of novel stimuli-responsive nanomaterials targeting hypoxia-tumor microenvironment (TME), and their applications in cancer diagnosis and therapy. Future prospect and challenges of nanomaterials are also discussed.

Microwave-assisted synthesis and upconversion luminescence of NaYF4:Yb, Gd, Er and NaYF4:Yb, Gd, Tm nanorods

Anisotropic rare-earth ion (RE3+) doped fluoride upconversion particles are emerging as a potential candidate in diverse areas, ranging from biomedical imaging to photonics. Here, we develop a facile strategy to synthesize NaYF4:Yb, Er, Gd and NaYF4:Yb, Tm, Gd upconversion nanorods via microwave synthesis route by controlling the synthesis time and compared the optical properties of similar nanorods prepared via solvothermal technique. With the increase in synthesis time, the phase of the particle was found to change from mixed-phase to purely hexagonal and the morphology of the particles change the mixed phase of spherical and rod-shaped particles to completely nanorods for a synthesis time of 60 minutes. Further, the intrinsically hydrophobic particles changed to hydrophilic by removal of oleic capping via acid treatment and the amine-functionalized silica coating. The upconversion luminescence, as well as laser power-dependent emission properties of the surface-modified particles, elucidate that the surface modification route influence the upconversion luminescence as well as solvent-dependent emission properties. Moreover, the laser power-dependent studies elucidate that the upconversion process in a multi-photon process.