Microwave-assisted one-step synthesis of acetate-capped NaYF4:Yb/Er upconversion nanocrystals and their application in bioimaging

Acetate-capped hydrophilic cubic phase NaYF4:Yb/Er upconversion nanophosphors were effectively synthesized in a single step employing a facile microwave-assisted synthesis route by applying relatively low temperatures in a short span of time compared to the conventional synthetic methods. The nanoparticles having a size of about 25 nm exhibit good upconversion luminescence property and can be well dispersed in aqueous solvents as-synthesized. These upconversion nanoparticles were examined for their cytotoxicity and demonstrated to be an effective material for cancer cell imaging using near-infrared radiation.