Preparation and drug-delivery properties of hollow YVO:Ln and mesoporous YVO:Ln@nSiO@mSiO (Ln = Eu, Yb, Er, and Ho).

In this paper, size-controlled morphologies of (Y, Gd)VO and (Y, Gd)VO:Ln (Ln = Eu, Yb, Er, and Ho) were obtained via a facile hydrothermal route, and their properties for drug delivery and photoluminescence were investigated. Monodisperse ellipsoid-like hollow (Y, Gd)VO were designed by employing (Y, Gd)(OH)CO colloidal spheres as a sacrificial template and NHVO as a vanadium source, and the formation mechanism could be interpreted by the Kirkendall effect. The control of particle size for hollow (Y, Gd)VO was realized, facilitating their practical application. Mesoporous core-shell structured (Y, Gd)VO:Ln@nSiO@mSiO were designed to improve the properties for drug release. Typically, red emission of YVO:Eu predominated under 465 nm excitation; the upconversion spectra of YVO:Yb, Er and YVO:Yb, Ho revealed green and red color upon 980 nm excitation, respectively. The biocompatibility and drug release evaluations indicate the potential biological applications of the samples.