Controlled synthesis, bioimaging and toxicity assessments in strong red emitting Mn2+ doped NaYF4:Yb3+/Ho3+ nanophosphors

: Reddy KL, Rai M, Prabhakar N, Arppe R, Rai SB, Singh SK, Rosenholm JM, Krishnan V

Publisher: ROYAL SOC CHEMISTRY

: 2016

: RSC Advances

: RSC ADVANCES

: RSC ADV

: 6

: 59

: 53698

: 53704

: 7

: 2046-2069

DOI: https://doi.org/10.1039/c6ra07106f

Rare earth, Yb3+/Ho3+ doped NaYF4 nanophosphors showed augmentation of visible green and red light emission by the introduction of Mn2+ as a co-dopant. Nanophosphors were characterized for their morphology and upconversion (UC) fluorescence, as a function of co-dopant concentration. The effect of Mn2+ doping has been investigated to explore the UC mechanism of the phosphors. With the introduction of Mn2+, the intensity of all the emission bands was increased, in particular the red band, which was most significant at 40 mol% doping. A possible mechanism for the enhancement of the red emission has been proposed. The prepared UC nanoparticles were functionalized with polyethylene glycol-polyethylene imine co-polymer to make them water dispersible and successfully applied for cancer cell imaging.