The potential toxicity and biocompatibility of sodium yttrium fluoride, erbium and ytterbium doped (NaYF4: Er3+, Yb3+) upconversion nanoparticles are of great importance for their biomedical applications. In this work, the acute toxicity of sodium yttrium fluoride, erbium and ytterbium doped (NaYF4: Er3+, Yb3+) upconversion nanomaterials toxicity was evaluated. Rats received intravenous injection ...