Chemistry Letters, Vol.46, No.8, 1076-1078, 2017
Enhanced Red Upconversion Emission of NaYF4:Yb3+, Er3+, Mn2+ Nanoparticles for Near-infrared-induced Photodynamic Therapy and Fluorescence Imaging
Polyethyleneimine (PEI)-capped NaYF4 nanoparticles (NPs) codoped with Yb3+, Er3+, and Mn2+ ions (MnUNPs) were synthesized via a solvothermal method. The MnUNPs showed tissue-penetrable over-1000nm (OTN-) near-infrared (NIR) and strong red upconversion (UC) emission under NIR excitation. Furthermore, the photosensitizers chlorin e6 (Ce6) and biocompatible poly(ethylene glycol) (PEG) were immobilized on the surface of the MnUNPs (PEG/Ce6-MnUNPs). The prepared PEG/Ce6-MnUNPs generated singlet oxygen (O-1(2)) and displayed effective anticancer activity under NIR excitation.