Encapsulation of 67Cu therapeutic radiometal in luminescent lanthanide phosphate core and core-shell nanoparticles.

Copper-67 (67Cu) has physical characteristics useful for both therapy and imaging. However, its applicability has been hindered by the complexity of obtaining large quantities of a product with high specific activity. With the advancement of 67Cu production methods, suitable radioisotope carriers are sought. Lanthanide phosphate nanoparticles have demonstrated their multifunctional characteristics for biomedical applications and, more recently, their potential in radiopharmaceuticals. Thus, we produced luminescent lanthanide phosphate nanoparticles with core and core-shell structures, incorporating 67Cu during their synthesis. The nanoparticles exhibited hexagonal crystalline structure and spherical morphology with sizes below 6 nm. The luminescent colloidal suspensions evidenced the characteristic 5D0-7FJ for Eu3+, providing the red color under UV light. A radiochemical yield of 67Cu >95% was obtained with both core and core-shell LaPO4:Eu. The core-shell nanoparticles reduced the release of 67Cu by a factor of ∼2 over that from the core, which continuously decreased with time. Multifunctional LnPO4 nanoparticles have the potential to be used as a carrier of single or multiple radioisotopes to enhance image-guided targeted nano-radiopharmaceutical therapy.

Pulsed laser deposition and ferroelectric characterization of nanostructured perovskite lead zirconate titanate (52/48) thin films.

Perovskite lead zirconate titanate nanostructured (PZT) thin films with Zr/Ti ratio of 52/48 were deposited on Pt/TiO2/SiO2/Si(100) substrate using pulsed laser deposition method. A metal/ ferroelectric/metal (MFM) structure was used for ferroelectric property measurements, formed by depositing gold electrode on top of the film. A Nd:YAG UV laser having a wavelength of 355 nm and an energy fluence of -2.7 J/cm2 was used to deposit the film. The film was deposited on platinum (Pt) coated silicon substrate at the substrate temperature of 600 degrees C and the base vacuum of 10(-6) mbar. The scanning electron microscopy (SEM) images revealed well-crystallized films with a fine microstructure and an average grain size of - 50 nm. The ferroelectric properties of the film were studied and the results were discussed. The voltage dependent Polarization versus Electric field hysteresis measurements of PZT (52/48) pellet showed a well-defined hysteresis loop with a fairly high remnant polarization (P(r)) and low coercive field (E(c)).